NIFI-2208 - initial commit Custom Property Expression Language support with Variable Registry, includes bug fix for NIFI-2057

This closes #529

Signed-off-by: jpercivall <joepercivall@yahoo.com>

nifi-api/src/main/java/org/apache/nifi/registry/FileVariableRegistry.java

@@ -0,0 +1,67 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.nifi.registry;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Map;
+
+
+abstract class FileVariableRegistry extends MultiMapVariableRegistry {
+
+    FileVariableRegistry() {
+        super();
+    }
+
+    FileVariableRegistry(File... files) throws IOException{
+        super();
+        addVariables(files);
+    }
+
+    FileVariableRegistry(Path... paths) throws IOException{
+        super();
+        addVariables(paths);
+    }
+
+    private void addVariables(File ...files) throws IOException{
+        if(files != null) {
+            for (final File file : files) {
+                Map<String,String> map = convertFile(file);
+                if(map != null) {
+                    registry.addMap(convertFile(file));
+                }
+            }
+
+        }
+    }
+
+    private void addVariables(Path ...paths) throws IOException{
+        if(paths != null) {
+            for (final Path path : paths) {
+                Map<String,String> map = convertFile(path.toFile());
+                if(map != null) {
+                    registry.addMap(map);
+                }
+            }
+        }
+    }
+
+    protected abstract Map<String,String> convertFile(File file) throws IOException;
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/ImmutableMultiMap.java

@@ -0,0 +1,145 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+public class ImmutableMultiMap<V> implements Map<String,V> {
+
+    private final List<Map<String,V>> maps;
+
+    ImmutableMultiMap() {
+        this.maps = new ArrayList<>();
+    }
+
+    @Override
+    public int size() {
+        return keySet().size();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        for (final Map<String,V> map : maps) {
+            if (!map.isEmpty()) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public boolean containsKey(final Object key) {
+        if (key == null) {
+            return false;
+        }
+
+        for (final Map<String,V> map : maps) {
+            if (map.containsKey(key)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public boolean containsValue(final Object value) {
+        for (final Map<String,V> map : maps) {
+            if (map.containsValue(value)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    @SuppressWarnings("rawtypes")
+    public V get(final Object key) {
+        if (key == null) {
+            throw new IllegalArgumentException("Null Keys are not allowed");
+        }
+
+        for (final Map<String,V> map : maps) {
+            final V val = map.get(key);
+            if (val != null) {
+                return val;
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public V put(String key, V value) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public V remove(Object key) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void putAll(Map<? extends String, ? extends V> m) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void clear() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    @SuppressWarnings({"unchecked", "rawtypes"})
+    public Set<String> keySet() {
+        final Set<String> keySet = new HashSet<>();
+        for (final Map map : maps) {
+            keySet.addAll(map.keySet());
+        }
+        return keySet;
+    }
+
+    @Override
+    @SuppressWarnings({"unchecked", "rawtypes"})
+    public Collection<V> values() {
+        final Set<V> values = new HashSet<>();
+        for (final Map map : maps) {
+            values.addAll(map.values());
+        }
+        return values;
+    }
+
+    @Override
+    @SuppressWarnings({"unchecked", "rawtypes"})
+    public Set<java.util.Map.Entry<String, V>> entrySet() {
+        final Set<java.util.Map.Entry<String, V>> entrySet = new HashSet<>();
+        for (final Map map : maps) {
+            entrySet.addAll(map.entrySet());
+        }
+        return entrySet;
+    }
+
+    @SuppressWarnings({"unchecked", "rawtypes"})
+    void addMap(Map<String,V> map){
+        this.maps.add(map);
+    }
+
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/MultiMapVariableRegistry.java

@@ -0,0 +1,70 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.util.Map;
+import java.util.Set;
+
+/***
+ * This implementation of variable registry uses the ImmutableMultiMap which stores one or more
+ * registries that can be searched, accessed and appended.  NOTE: Duplicate values within
+ * or between added registries will be stored however on retrieval the first value encountered will be returned.
+ * */
+public class MultiMapVariableRegistry implements VariableRegistry {
+
+    protected final ImmutableMultiMap<String> registry;
+
+    MultiMapVariableRegistry() {
+        this.registry = new ImmutableMultiMap<>();
+    }
+
+    @SafeVarargs
+    MultiMapVariableRegistry(Map<String,String>...maps){
+        this();
+        if(maps != null) {
+            for (Map<String, String> map : maps) {
+                addVariables(map);
+            }
+        }
+    }
+
+    public void addVariables(Map<String, String> map) {
+        this.registry.addMap(map);
+    }
+
+    @Override
+    public void addRegistry(VariableRegistry variableRegistry) {
+        if(variableRegistry != null && !variableRegistry.getVariables().isEmpty()) {
+            this.registry.addMap(variableRegistry.getVariables());
+        }
+    }
+
+    @Override
+    public Map<String, String> getVariables() {
+        return registry;
+    }
+
+    @Override
+    public String getVariableValue(String variable) {
+        return registry.get(variable);
+    }
+
+    @Override
+    public Set<String> getVariableNames() {
+        return this.registry.keySet();
+    }
+}

nifi-api/src/main/java/org/apache/nifi/registry/PropertiesVariableRegistry.java

@@ -0,0 +1,82 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Properties;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+class PropertiesVariableRegistry extends FileVariableRegistry {
+
+    private static final Logger LOG = LoggerFactory.getLogger(PropertiesVariableRegistry.class);
+
+    PropertiesVariableRegistry(File... files) throws IOException{
+        super(files);
+    }
+
+    PropertiesVariableRegistry(Path... paths) throws IOException {
+        super(paths);
+    }
+
+    PropertiesVariableRegistry(Properties...properties){
+        super();
+        addVariables(properties);
+    }
+
+    private void addVariables(Properties... properties){
+        if(properties != null) {
+            for (Properties props : properties) {
+                addVariables(convertToMap(props));
+            }
+        }
+    }
+
+    @Override
+    protected Map<String,String> convertFile(File file) throws IOException{
+
+        if(file.exists()) {
+            try (final InputStream inStream = new BufferedInputStream(new FileInputStream(file))) {
+                Properties properties = new Properties();
+                properties.load(inStream);
+                return convertToMap(properties);
+            }
+        }else{
+            LOG.warn("Could not add file " + file.getName() + ". file did not exist.");
+            return null;
+        }
+
+    }
+
+    private Map<String,String> convertToMap(Properties properties){
+        HashMap<String,String> propertiesMap = new HashMap<>(properties.keySet().size());
+        for(Object key:  properties.keySet()){
+            propertiesMap.put((String)key,(String) properties.get(key));
+        }
+        return propertiesMap;
+    }
+
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/VariableRegistry.java

@@ -0,0 +1,60 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+
+import java.util.Map;
+import java.util.Set;
+
+/**
+ *  Access key/value pairs throughout the application.
+ */
+public interface VariableRegistry {
+
+    /**
+     * Returns a map of key/value pairs stored in the registry
+     *  @return variables
+     **/
+    Map<String, String> getVariables();
+
+    /**
+     * Return a value for a given variable
+     * @param variable variable
+     * @return value
+     **/
+    String getVariableValue(String variable);
+
+    /**
+     * Concatenate a variable registry
+     * @param variableRegistry variableRegistry
+     * */
+    void addRegistry(VariableRegistry variableRegistry);
+
+    /**
+     * Returns a set variable names in the registry
+     * @return variableNames
+     **/
+    Set<String> getVariableNames();
+
+    /**
+     * Concatenate variable key value pair to registry
+     * @param variables variable Map
+     * */
+    void addVariables(Map<String,String> variables);
+
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/VariableRegistryFactory.java

@@ -0,0 +1,48 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.Properties;
+
+public class VariableRegistryFactory {
+
+    public static VariableRegistry getPropertiesInstance(final Properties...properties){
+        return new PropertiesVariableRegistry(properties);
+    }
+
+    public static VariableRegistry getPropertiesInstance(final Path... paths) throws IOException{
+        return new PropertiesVariableRegistry(paths);
+    }
+
+    public static VariableRegistry getPropertiesInstance(final File ...files) throws IOException{
+        return new PropertiesVariableRegistry(files);
+    }
+
+    @SafeVarargs
+    public static VariableRegistry getInstance(final Map<String,String> ...maps){
+        return new MultiMapVariableRegistry(maps);
+    }
+
+    public static VariableRegistry getInstance(){
+        return new MultiMapVariableRegistry();
+    }
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/VariableRegistryProvider.java

@@ -0,0 +1,23 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+public interface VariableRegistryProvider {
+
+    VariableRegistry getVariableRegistry();
+
+}

nifi-api/src/main/java/org/apache/nifi/registry/VariableRegistryUtils.java

@@ -0,0 +1,87 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.nifi.flowfile.FlowFile;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class VariableRegistryUtils {
+
+    private final static Logger LOG =  LoggerFactory.getLogger(VariableRegistryUtils.class);
+
+    public static VariableRegistry createSystemVariableRegistry(){
+        VariableRegistry variableRegistry = VariableRegistryFactory.getInstance();
+        VariableRegistry propRegistry = VariableRegistryFactory.getPropertiesInstance(System.getProperties());
+        VariableRegistry envRegistry = VariableRegistryFactory.getInstance(System.getenv());
+        variableRegistry.addRegistry(propRegistry);
+        variableRegistry.addRegistry(envRegistry);
+        return variableRegistry;
+    }
+
+    public static VariableRegistry createCustomVariableRegistry(Path[] properties){
+
+        VariableRegistry customRegistry = null;
+        try {
+            customRegistry = VariableRegistryFactory.getPropertiesInstance(properties);
+            customRegistry.addRegistry(createSystemVariableRegistry());
+        } catch (IOException ioe){
+            LOG.error("Exception thrown while attempting to add properties to registry",ioe);
+        }
+        return customRegistry;
+    }
+
+    public static VariableRegistry createFlowVariableRegistry(VariableRegistry variableRegistry, final FlowFile flowFile, final Map<String, String> additionalAttributes){
+        final Map<String, String> flowFileAttributes = flowFile == null ? null : flowFile.getAttributes();
+        final Map<String, String> additionalMap = additionalAttributes == null ? null : additionalAttributes;
+
+        Map<String, String> flowFileProps = null;
+        if (flowFile != null) {
+            flowFileProps = new HashMap<>();
+            flowFileProps.put("flowFileId", String.valueOf(flowFile.getId()));
+            flowFileProps.put("fileSize", String.valueOf(flowFile.getSize()));
+            flowFileProps.put("entryDate", String.valueOf(flowFile.getEntryDate()));
+            flowFileProps.put("lineageStartDate", String.valueOf(flowFile.getLineageStartDate()));
+            flowFileProps.put("lastQueueDate",String.valueOf(flowFile.getLastQueueDate()));
+            flowFileProps.put("queueDateIndex",String.valueOf(flowFile.getQueueDateIndex()));
+        }
+
+        VariableRegistry newRegistry = VariableRegistryFactory.getInstance();
+
+        if(flowFileAttributes != null) {
+            newRegistry.addVariables(flowFileAttributes);
+        }
+        if(additionalMap != null) {
+            newRegistry.addVariables(additionalMap);
+        }
+        if(flowFileProps != null) {
+            newRegistry.addVariables(flowFileProps);
+        }
+
+        if(variableRegistry != null) {
+            newRegistry.addRegistry(variableRegistry);
+        }
+
+        return newRegistry;
+    }
+
+}

nifi-api/src/test/java/org/apache/nifi/registry/TestVariableRegistry.java

@@ -0,0 +1,170 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.nifi.registry;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Properties;
+import java.util.Set;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+
+public class TestVariableRegistry {
+
+    @Test
+    public void testReadMap(){
+        Map<String,String> variables1 = new HashMap<>();
+        variables1.put("fake.property.1","fake test value");
+
+        Map<String,String> variables2 = new HashMap<>();
+        variables1.put("fake.property.2","fake test value");
+
+        VariableRegistry registry = VariableRegistryFactory.getInstance(variables1,variables2);
+
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.size() == 2);
+        assertTrue(variables.get("fake.property.1").equals("fake test value"));
+        assertTrue(registry.getVariableValue("fake.property.2").equals("fake test value"));
+    }
+
+    @Test
+    public void testReadProperties(){
+        Properties properties = new Properties();
+        properties.setProperty("fake.property.1","fake test value");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(properties);
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.get("fake.property.1").equals("fake test value"));
+    }
+
+    @Test
+    public void testReadFiles() throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(fooPath.toFile(),testPath.toFile());
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.size() == 3);
+        assertTrue(variables.get("fake.property.1").equals("test me out 1"));
+        assertTrue(variables.get("fake.property.3").equals("test me out 3, test me out 4"));
+    }
+
+    @Test
+    public void testExcludeInvalidFiles() throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        final Path fakePath = Paths.get("src/test/resources/TestVariableRegistry/fake.properties");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(fooPath.toFile(),testPath.toFile(),fakePath.toFile());
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.size() == 3);
+        assertTrue(variables.get("fake.property.1").equals("test me out 1"));
+        assertTrue(variables.get("fake.property.3").equals("test me out 3, test me out 4"));
+    }
+
+
+    @Test
+    public void testReadPaths() throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(fooPath,testPath);
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.size() == 3);
+        assertTrue(variables.get("fake.property.1").equals("test me out 1"));
+        assertTrue(variables.get("fake.property.3").equals("test me out 3, test me out 4"));
+    }
+
+    @Test
+    public void testExcludeInvalidPaths() throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        final Path fakePath = Paths.get("src/test/resources/TestVariableRegistry/fake.properties");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(fooPath,testPath,fakePath);
+        Map<String,String> variables = registry.getVariables();
+        assertTrue(variables.size() == 3);
+    }
+
+    @Test
+    public void testAddRegistry() throws IOException{
+
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        VariableRegistry pathRegistry = VariableRegistryFactory.getPropertiesInstance(fooPath);
+
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        VariableRegistry fileRegistry = VariableRegistryFactory.getPropertiesInstance(testPath.toFile());
+
+        Properties properties = new Properties();
+        properties.setProperty("fake.property.5","test me out 5");
+        VariableRegistry propRegistry = VariableRegistryFactory.getPropertiesInstance(properties);
+
+        propRegistry.addRegistry(pathRegistry);
+        propRegistry.addRegistry(fileRegistry);
+
+        Map<String,String> variables = propRegistry.getVariables();
+        assertTrue(variables.size() == 4);
+    }
+
+    @Test
+    public void testAttemptToAddNullRegistry() throws IOException{
+
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        VariableRegistry pathRegistry = VariableRegistryFactory.getPropertiesInstance(fooPath);
+        VariableRegistry nullRegistry = null;
+        pathRegistry.addRegistry(nullRegistry);
+        assertTrue(pathRegistry.getVariables().size() == 1);
+    }
+
+    @Test
+    public void testNoOverwriteRegistry()throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        VariableRegistry pathRegistry = VariableRegistryFactory.getPropertiesInstance(fooPath);
+
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        VariableRegistry fileRegistry = VariableRegistryFactory.getPropertiesInstance(testPath.toFile());
+
+        Properties properties = new Properties();
+        properties.setProperty("fake.property.3","test me out 5");
+        VariableRegistry propRegistry = VariableRegistryFactory.getPropertiesInstance(properties);
+
+        propRegistry.addRegistry(pathRegistry);
+        propRegistry.addRegistry(fileRegistry);
+
+        Map<String,String> variables = propRegistry.getVariables();
+        String testDuplicate = propRegistry.getVariableValue("fake.property.3");
+        assertTrue(variables.size() == 3);
+        assertTrue(testDuplicate.equals("test me out 5"));
+    }
+
+    @Test
+    public void testGetVariableNames() throws IOException{
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(fooPath,testPath);
+        Set<String> variableNames= registry.getVariableNames();
+        assertTrue(variableNames.size() == 3);
+        assertTrue(variableNames.contains("fake.property.1"));
+        assertTrue(variableNames.contains("fake.property.2"));
+        assertTrue(variableNames.contains("fake.property.3"));
+        assertTrue(!variableNames.contains("fake.property.4"));
+    }
+
+
+
+}

nifi-api/src/test/java/org/apache/nifi/registry/TestVariableRegistryUtils.java

@@ -0,0 +1,143 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.registry;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.nifi.flowfile.FlowFile;
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+
+public class TestVariableRegistryUtils {
+
+    @Test
+    public void testCreateSystemVariableRegistry(){
+        System.setProperty("fake","test");
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
+        Map<String,String> variables = variableRegistry.getVariables();
+        assertTrue(variables.containsKey("PATH"));
+        assertTrue(variables.get("fake").equals("test"));
+    }
+
+    @Test
+    public void testCreateCustomVariableRegistry(){
+        final Path fooPath = Paths.get("src/test/resources/TestVariableRegistry/foobar.properties");
+        final Path testPath = Paths.get("src/test/resources/TestVariableRegistry/test.properties");
+        Path[] paths = {fooPath,testPath};
+        System.setProperty("fake","test");
+        VariableRegistry variableRegistry = VariableRegistryUtils.createCustomVariableRegistry(paths);
+        Map<String,String> variables = variableRegistry.getVariables();
+        assertTrue(variables.containsKey("PATH"));
+        assertTrue(variables.containsKey("fake.property.3"));
+        assertTrue(variables.get("fake").equals("test"));
+        assertTrue(variables.get("fake.property.3").equals("test me out 3, test me out 4"));
+    }
+
+    @Test
+    public void testCreateFlowVariableRegistry(){
+        System.setProperty("fake","test");
+        FlowFile flowFile = createFlowFile();
+
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
+        VariableRegistry populatedRegistry = VariableRegistryUtils.createFlowVariableRegistry(variableRegistry,flowFile,null);
+        Map<String,String> variables = populatedRegistry.getVariables();
+        assertTrue(variables.containsKey("PATH"));
+        assertTrue(variables.get("fake").equals("test"));
+        assertTrue(variables.get("flowFileId").equals("1"));
+        assertTrue(variables.get("fileSize").equals("50"));
+        assertTrue(variables.get("entryDate").equals("1000"));
+        assertTrue(variables.get("lineageStartDate").equals("10000"));
+        assertTrue(variables.get("filename").equals("fakefile.txt"));
+    }
+
+    @Test
+    public void testPopulateRegistryWithEmptyFlowFileAndAttributes(){
+        System.setProperty("fake","test");
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
+        VariableRegistry populatedRegistry = VariableRegistryUtils.createFlowVariableRegistry(variableRegistry,null,null);
+        Map<String,String> variables = populatedRegistry.getVariables();
+        assertTrue( variables.containsKey("PATH"));
+        assertTrue( variables.get("fake").equals("test"));
+    }
+
+
+    private FlowFile createFlowFile(){
+        return  new FlowFile() {
+            @Override
+            public long getId() {
+                return 1;
+            }
+
+            @Override
+            public long getEntryDate() {
+                return 1000;
+            }
+
+            @Override
+            public long getLineageStartDate() {
+                return 10000;
+            }
+
+            @Override
+            public Long getLastQueueDate() {
+                return null;
+            }
+
+            @Override
+            public boolean isPenalized() {
+                return false;
+            }
+
+            @Override
+            public String getAttribute(String key) {
+                return null;
+            }
+
+            @Override
+            public long getSize() {
+                return 50;
+            }
+
+            @Override
+            public long getLineageStartIndex() {
+                return 0;
+            }
+
+            @Override
+            public long getQueueDateIndex() {
+                return 0;
+            }
+
+            @Override
+            public Map<String, String> getAttributes() {
+                Map<String,String> attributes = new HashMap<>();
+                attributes.put("filename","fakefile.txt");
+                return attributes;
+            }
+
+            @Override
+            public int compareTo(FlowFile o) {
+                return 0;
+            }
+        };
+    }
+
+}

nifi-api/src/test/resources/TestVariableRegistry/foobar.properties

@@ -0,0 +1,16 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+fake.property.3=test me out 3, test me out 4

nifi-api/src/test/resources/TestVariableRegistry/test.properties

@@ -0,0 +1,17 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+fake.property.1=test me out 1
+fake.property.2=test me out 2

nifi-bootstrap/pom.xml

@@ -41,5 +41,10 @@
 			<groupId>org.apache.nifi</groupId>
 			<artifactId>nifi-expression-language</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.spockframework</groupId>
+			<artifactId>spock-core</artifactId>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 </project>

nifi-bootstrap/src/main/java/org/apache/nifi/bootstrap/NotificationServiceManager.java

@@ -46,6 +46,8 @@ import org.apache.nifi.components.PropertyDescriptor;
 import org.apache.nifi.components.PropertyValue;
 import org.apache.nifi.components.ValidationContext;
 import org.apache.nifi.components.ValidationResult;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.w3c.dom.Document;
@@ -62,8 +64,15 @@ public class NotificationServiceManager {
 
     private final ScheduledExecutorService notificationExecutor;
     private int maxAttempts = 5;
+    private final VariableRegistry variableRegistry;
+
 
     public NotificationServiceManager() {
+        this(VariableRegistryUtils.createSystemVariableRegistry());
+    }
+
+    NotificationServiceManager(VariableRegistry variableRegistry){
+        this.variableRegistry = variableRegistry;
         notificationExecutor = Executors.newScheduledThreadPool(1, new ThreadFactory() {
             @Override
             public Thread newThread(final Runnable r) {
@@ -141,7 +150,7 @@ public class NotificationServiceManager {
                 }
 
                 // Check if the service is valid; if not, warn now so that users know this before they fail to receive notifications
-                final ValidationContext validationContext = new NotificationValidationContext(buildNotificationContext(config));
+                final ValidationContext validationContext = new NotificationValidationContext(buildNotificationContext(config), variableRegistry);
                 final Collection<ValidationResult> validationResults = service.validate(validationContext);
                 final List<String> invalidReasons = new ArrayList<>();
 
@@ -179,7 +188,7 @@ public class NotificationServiceManager {
                 @Override
                 public void run() {
                     // Check if the service is valid; if not, warn now so that users know this before they fail to receive notifications
-                    final ValidationContext validationContext = new NotificationValidationContext(buildNotificationContext(config));
+                    final ValidationContext validationContext = new NotificationValidationContext(buildNotificationContext(config), variableRegistry);
                     final Collection<ValidationResult> validationResults = service.validate(validationContext);
                     final List<String> invalidReasons = new ArrayList<>();
 
@@ -247,7 +256,7 @@ public class NotificationServiceManager {
                     configuredValue = fullPropDescriptor.getDefaultValue();
                 }
 
-                return new StandardPropertyValue(configuredValue, null);
+                return new StandardPropertyValue(configuredValue, null, variableRegistry);
             }
 
             @Override
@@ -364,7 +373,7 @@ public class NotificationServiceManager {
                         value = descriptor.getDefaultValue();
                     }
 
-                    return new StandardPropertyValue(value, null);
+                    return new StandardPropertyValue(value, null, variableRegistry);
                 }
 
                 @Override

nifi-bootstrap/src/main/java/org/apache/nifi/bootstrap/notification/NotificationValidationContext.java

@@ -30,12 +30,14 @@ import org.apache.nifi.components.ValidationContext;
 import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.ControllerServiceLookup;
 import org.apache.nifi.expression.ExpressionLanguageCompiler;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class NotificationValidationContext implements ValidationContext {
     private final NotificationContext context;
     private final Map<String, Boolean> expressionLanguageSupported;
+    private final VariableRegistry variableRegistry;
 
-    public NotificationValidationContext(final NotificationContext processContext) {
+    public NotificationValidationContext(final NotificationContext processContext, VariableRegistry variableRegistry) {
         this.context = processContext;
 
         final Map<PropertyDescriptor, String> properties = processContext.getProperties();
@@ -43,17 +45,19 @@ public class NotificationValidationContext implements ValidationContext {
         for (final PropertyDescriptor descriptor : properties.keySet()) {
             expressionLanguageSupported.put(descriptor.getName(), descriptor.isExpressionLanguageSupported());
         }
+        this.variableRegistry = variableRegistry;
     }
 
 
     @Override
     public PropertyValue newPropertyValue(final String rawValue) {
-        return new StandardPropertyValue(rawValue, null);
+        return new StandardPropertyValue(rawValue, null, variableRegistry);
     }
 
     @Override
     public ExpressionLanguageCompiler newExpressionLanguageCompiler() {
-        return new StandardExpressionLanguageCompiler();
+
+        return new StandardExpressionLanguageCompiler(null);
     }
 
     @Override

nifi-bootstrap/src/test/groovy/org/apache/nifi/bootstrap/NotificationServiceManagerSpec.groovy

@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.nifi.bootstrap
+
+import org.apache.nifi.bootstrap.notification.NotificationType
+import org.apache.nifi.registry.VariableRegistry
+import spock.lang.Specification
+import java.nio.file.Paths
+
+class NotificationServiceManagerSpec extends Specification{
+
+    def setupSpec(){
+    }
+
+    def "should acess variable registry to replace EL values"(){
+
+        given:
+            def mockRegistry = Mock(VariableRegistry.class)
+            def notificationServiceManager = new NotificationServiceManager(mockRegistry);
+            def file = Paths.get("src/test/resources/notification-services.xml").toFile()
+            notificationServiceManager.loadNotificationServices(file)
+            //testing with stopped becasue it will block until method is completed
+            notificationServiceManager.registerNotificationService(NotificationType.NIFI_STOPPED,"custom-notification")
+
+        when:
+            notificationServiceManager.notify(NotificationType.NIFI_STOPPED,"NiFi Stopped","NiFi Stopped")
+
+        then:
+            6 * mockRegistry.getVariables() >> ["test.server":"smtp://fakeserver.com","test.username":"user","test.password":"pass"]
+
+
+    }
+
+
+}

nifi-bootstrap/src/test/groovy/org/apache/nifi/bootstrap/notification/TestCustomNotificationService.java

@@ -0,0 +1,85 @@
+package org.apache.nifi.bootstrap.notification;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.nifi.components.PropertyDescriptor;
+import org.apache.nifi.processor.util.StandardValidators;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class TestCustomNotificationService extends AbstractNotificationService {
+
+    private static Logger logger = LoggerFactory.getLogger(TestCustomNotificationService.class);
+
+    public static final PropertyDescriptor CUSTOM_HOSTNAME = new PropertyDescriptor.Builder()
+            .name("Custom Hostname")
+            .description("The hostname of the Custom Server that is used to send notifications")
+            .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+            .expressionLanguageSupported(true)
+            .required(true)
+            .build();
+    public static final PropertyDescriptor CUSTOM_USERNAME = new PropertyDescriptor.Builder()
+            .name("Custom Username")
+            .description("Username for the account")
+            .expressionLanguageSupported(true)
+            .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+            .required(false)
+            .build();
+    public static final PropertyDescriptor CUSTOM_PASSWORD = new PropertyDescriptor.Builder()
+            .name("Custom Password")
+            .description("Password for the account")
+            .expressionLanguageSupported(true)
+            .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+            .required(false)
+            .sensitive(true)
+            .build();
+
+    /**
+     * Mapping of the mail properties to the NiFi PropertyDescriptors that will be evaluated at runtime
+     */
+    private static final Map<String, PropertyDescriptor> propertyToContext = new HashMap<>();
+
+    static {
+        propertyToContext.put("custom.host", CUSTOM_HOSTNAME);
+        propertyToContext.put("custom.user", CUSTOM_USERNAME);
+        propertyToContext.put("custom.password", CUSTOM_PASSWORD);
+    }
+
+    @Override
+    protected List<PropertyDescriptor> getSupportedPropertyDescriptors() {
+        final List<PropertyDescriptor> properties = new ArrayList<>();
+        properties.add(CUSTOM_HOSTNAME);
+        properties.add(CUSTOM_USERNAME);
+        properties.add(CUSTOM_PASSWORD);
+        return properties;
+    }
+
+    @Override
+    public void notify(NotificationContext context, String subject, String message) throws NotificationFailedException {
+        logger.info(context.getProperty(CUSTOM_HOSTNAME).evaluateAttributeExpressions().getValue());
+        logger.info(context.getProperty(CUSTOM_USERNAME).evaluateAttributeExpressions().getValue());
+        logger.info(context.getProperty(CUSTOM_PASSWORD).evaluateAttributeExpressions().getValue());
+    }
+
+
+}

nifi-bootstrap/src/test/resources/notification-services.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Licensed to the Apache Software Foundation (ASF) under one or more
+  contributor license agreements.  See the NOTICE file distributed with
+  this work for additional information regarding copyright ownership.
+  The ASF licenses this file to You under the Apache License, Version 2.0
+  (the "License"); you may not use this file except in compliance with
+  the License.  You may obtain a copy of the License at
+      http://www.apache.org/licenses/LICENSE-2.0
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<services>
+         <service>
+            <id>custom-notification</id>
+            <class>org.apache.nifi.bootstrap.notification.TestCustomNotificationService</class>
+            <property name="Custom Hostname">${test.server}</property>
+            <property name="Custom Username">${test.username}</property>
+            <property name="Custom Password">${test.password}</property>
+         </service>
+</services>

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/EmptyPreparedQuery.java

@@ -16,11 +16,10 @@
  */
 package org.apache.nifi.attribute.expression.language;
 
-import java.util.Map;
 
 import org.apache.nifi.expression.AttributeValueDecorator;
-import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class EmptyPreparedQuery implements PreparedQuery {
 
@@ -31,37 +30,7 @@ public class EmptyPreparedQuery implements PreparedQuery {
     }
 
     @Override
-    public String evaluateExpressions(final FlowFile flowFile, final AttributeValueDecorator decorator) throws ProcessException {
+    public String evaluateExpressions(VariableRegistry variableRegistry, AttributeValueDecorator decorator) throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions() throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions(final AttributeValueDecorator decorator) throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions(final FlowFile flowFile) throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions(Map<String, String> attributes) throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions(Map<String, String> attributes, AttributeValueDecorator decorator) throws ProcessException {
-        return value;
-    }
-
-    @Override
-    public String evaluateExpressions(FlowFile flowFile, Map<String, String> additionalAttributes, AttributeValueDecorator decorator) throws ProcessException {
         return value;
     }
 }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/InvalidPreparedQuery.java

@@ -16,12 +16,11 @@
  */
 package org.apache.nifi.attribute.expression.language;
 
-import java.util.Map;
 
 import org.apache.nifi.attribute.expression.language.exception.AttributeExpressionLanguageException;
 import org.apache.nifi.expression.AttributeValueDecorator;
-import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 
 /**
  * An implementation of PreparedQuery that throws an
@@ -40,37 +39,9 @@ public class InvalidPreparedQuery implements PreparedQuery {
     }
 
     @Override
-    public String evaluateExpressions(final FlowFile flowFile, final AttributeValueDecorator decorator) throws ProcessException {
+    public String evaluateExpressions(final VariableRegistry variableRegistry, final AttributeValueDecorator decorator) throws ProcessException {
         throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
     }
 
-    @Override
-    public String evaluateExpressions() throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
 
-    @Override
-    public String evaluateExpressions(final AttributeValueDecorator decorator) throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
-
-    @Override
-    public String evaluateExpressions(final FlowFile flowFile) throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
-
-    @Override
-    public String evaluateExpressions(final Map<String, String> attributes) throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
-
-    @Override
-    public String evaluateExpressions(final Map<String, String> attributes, final AttributeValueDecorator decorator) throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
-
-    @Override
-    public String evaluateExpressions(FlowFile flowFile, Map<String, String> additionalAttributes, AttributeValueDecorator decorator) throws ProcessException {
-        throw new AttributeExpressionLanguageException("Invalid Expression: " + query + " due to " + explanation);
-    }
 }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/PreparedQuery.java

@@ -16,25 +16,13 @@
  */
 package org.apache.nifi.attribute.expression.language;
 
-import java.util.Map;
 
 import org.apache.nifi.expression.AttributeValueDecorator;
-import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 
 public interface PreparedQuery {
 
-    String evaluateExpressions(FlowFile flowFile, AttributeValueDecorator decorator) throws ProcessException;
+    String evaluateExpressions(VariableRegistry registry, AttributeValueDecorator decorator) throws ProcessException;
 
-    String evaluateExpressions() throws ProcessException;
-
-    String evaluateExpressions(AttributeValueDecorator decorator) throws ProcessException;
-
-    String evaluateExpressions(FlowFile flowFile) throws ProcessException;
-
-    String evaluateExpressions(Map<String, String> attributes) throws ProcessException;
-
-    String evaluateExpressions(Map<String, String> attributes, AttributeValueDecorator decorator) throws ProcessException;
-
-    String evaluateExpressions(FlowFile flowFile, Map<String, String> additionalAttributes, AttributeValueDecorator decorator) throws ProcessException;
 }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/Query.java

@@ -18,13 +18,9 @@ package org.apache.nifi.attribute.expression.language;
 
 import java.net.UnknownHostException;
 import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionLexer;
@@ -198,6 +194,7 @@ import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpre
 import static org.apache.nifi.attribute.expression.language.antlr.AttributeExpressionParser.UUID;
 
 import org.apache.nifi.attribute.expression.language.evaluation.selection.MappingEvaluator;
+import org.apache.nifi.registry.VariableRegistry;
 
 /**
  * Class used for creating and evaluating NiFi Expression Language. Once a Query
@@ -367,8 +364,8 @@ public class Query {
         return -1;
     }
 
-    static String evaluateExpression(final Tree tree, final String queryText, final Map<String, String> expressionMap, final AttributeValueDecorator decorator) throws ProcessException {
+    static String evaluateExpression(final Tree tree, final String queryText, final VariableRegistry registry, final AttributeValueDecorator decorator) throws ProcessException {
-        final Object evaluated = Query.fromTree(tree, queryText).evaluate(expressionMap).getValue();
+        final Object evaluated = Query.fromTree(tree, queryText).evaluate(registry).getValue();
         if (evaluated == null) {
             return null;
         }
@@ -378,29 +375,12 @@ public class Query {
         return decorator == null ? escaped : decorator.decorate(escaped);
     }
 
-    static String evaluateExpressions(final String rawValue, Map<String, String> expressionMap) throws ProcessException {
+    static String evaluateExpressions(final String rawValue, VariableRegistry registry) throws ProcessException {
-        return evaluateExpressions(rawValue, expressionMap, null);
+        return evaluateExpressions(rawValue, registry, null);
     }
 
-    static String evaluateExpressions(final String rawValue) throws ProcessException {
+    static String evaluateExpressions(final String rawValue, VariableRegistry registry, final AttributeValueDecorator decorator) throws ProcessException {
-        return evaluateExpressions(rawValue, createExpressionMap(null), null);
+        return Query.prepare(rawValue).evaluateExpressions(registry, decorator);
-    }
-
-    static String evaluateExpressions(final String rawValue, final FlowFile flowFile) throws ProcessException {
-        return evaluateExpressions(rawValue, createExpressionMap(flowFile), null);
-    }
-
-    static String evaluateExpressions(final String rawValue, Map<String, String> expressionMap, final AttributeValueDecorator decorator) throws ProcessException {
-        return Query.prepare(rawValue).evaluateExpressions(expressionMap, decorator);
-    }
-
-    public static String evaluateExpressions(final String rawValue, final FlowFile flowFile, final AttributeValueDecorator decorator) throws ProcessException {
-        if (rawValue == null) {
-            return null;
-        }
-
-        final Map<String, String> expressionMap = createExpressionMap(flowFile);
-        return evaluateExpressions(rawValue, expressionMap, decorator);
     }
 
     private static Evaluator<?> getRootSubjectEvaluator(final Evaluator<?> evaluator) {
@@ -426,150 +406,6 @@ public class Query {
         return value.replaceAll("\\$\\$(?=\\$*\\{.*?\\})", "\\$");
     }
 
-    static Map<String, String> createExpressionMap(final FlowFile flowFile) {
-        return createExpressionMap(flowFile, null);
-    }
-
-    static Map<String, String> createExpressionMap(final FlowFile flowFile, final Map<String, String> additionalAttributes) {
-        final Map<String, String> attributeMap = flowFile == null ? Collections.emptyMap() : flowFile.getAttributes();
-        final Map<String, String> additionalOrEmpty = additionalAttributes == null ? Collections.emptyMap() : additionalAttributes;
-        final Map<String, String> envMap = System.getenv();
-        final Map<?, ?> sysProps = System.getProperties();
-
-        final Map<String, String> flowFileProps = new HashMap<>();
-        if (flowFile != null) {
-            flowFileProps.put("flowFileId", String.valueOf(flowFile.getId()));
-            flowFileProps.put("fileSize", String.valueOf(flowFile.getSize()));
-            flowFileProps.put("entryDate", String.valueOf(flowFile.getEntryDate()));
-            flowFileProps.put("lineageStartDate", String.valueOf(flowFile.getLineageStartDate()));
-        }
-
-        return wrap(additionalOrEmpty, attributeMap, flowFileProps, envMap, sysProps);
-    }
-
-    private static Map<String, String> wrap(final Map<String, String> additional, final Map<String, String> attributes, final Map<String, String> flowFileProps,
-        final Map<String, String> env, final Map<?, ?> sysProps) {
-        @SuppressWarnings("rawtypes")
-        final Map[] maps = new Map[] {additional, attributes, flowFileProps, env, sysProps};
-
-        return new Map<String, String>() {
-            @Override
-            public int size() {
-                int size = 0;
-                for (final Map<?, ?> map : maps) {
-                    size += map.size();
-                }
-                return size;
-            }
-
-            @Override
-            public boolean isEmpty() {
-                for (final Map<?, ?> map : maps) {
-                    if (!map.isEmpty()) {
-                        return false;
-                    }
-                }
-                return true;
-            }
-
-            @Override
-            public boolean containsKey(final Object key) {
-                if (key == null) {
-                    return false;
-                }
-                if (!(key instanceof String)) {
-                    return false;
-                }
-
-                for (final Map<?, ?> map : maps) {
-                    if (map.containsKey(key)) {
-                        return true;
-                    }
-                }
-                return false;
-            }
-
-            @Override
-            public boolean containsValue(final Object value) {
-                for (final Map<?, ?> map : maps) {
-                    if (map.containsValue(value)) {
-                        return true;
-                    }
-                }
-                return false;
-            }
-
-            @Override
-            @SuppressWarnings("rawtypes")
-            public String get(final Object key) {
-                if (key == null) {
-                    throw new IllegalArgumentException("Null Keys are not allowed");
-                }
-                if (!(key instanceof String)) {
-                    return null;
-                }
-
-                for (final Map map : maps) {
-                    final Object val = map.get(key);
-                    if (val != null) {
-                        return String.valueOf(val);
-                    }
-                }
-                return null;
-            }
-
-            @Override
-            public String put(String key, String value) {
-                throw new UnsupportedOperationException();
-            }
-
-            @Override
-            public String remove(final Object key) {
-                throw new UnsupportedOperationException();
-            }
-
-            @Override
-            public void putAll(final Map<? extends String, ? extends String> m) {
-                throw new UnsupportedOperationException();
-            }
-
-            @Override
-            public void clear() {
-                throw new UnsupportedOperationException();
-            }
-
-            @Override
-            @SuppressWarnings({"unchecked", "rawtypes"})
-            public Set<String> keySet() {
-                final Set<String> keySet = new HashSet<>();
-                for (final Map map : maps) {
-                    keySet.addAll(map.keySet());
-                }
-                return keySet;
-            }
-
-            @Override
-            @SuppressWarnings({"unchecked", "rawtypes"})
-            public Collection<String> values() {
-                final Set<String> values = new HashSet<>();
-                for (final Map map : maps) {
-                    values.addAll(map.values());
-                }
-                return values;
-            }
-
-            @Override
-            @SuppressWarnings({"unchecked", "rawtypes"})
-            public Set<java.util.Map.Entry<String, String>> entrySet() {
-                final Set<java.util.Map.Entry<String, String>> entrySet = new HashSet<>();
-                for (final Map map : maps) {
-                    entrySet.addAll(map.entrySet());
-                }
-                return entrySet;
-            }
-
-        };
-    }
 
     public static Query fromTree(final Tree tree, final String text) {
         return new Query(text, tree, buildEvaluator(tree));
@@ -706,20 +542,12 @@ public class Query {
         return evaluator.getResultType();
     }
 
-    QueryResult<?> evaluate() {
+    QueryResult<?> evaluate(final VariableRegistry registry) {
-        return evaluate(createExpressionMap(null));
-    }
-
-    QueryResult<?> evaluate(final FlowFile flowFile) {
-        return evaluate(createExpressionMap(flowFile));
-    }
-
-    QueryResult<?> evaluate(final Map<String, String> attributes) {
         if (evaluated.getAndSet(true)) {
             throw new IllegalStateException("A Query cannot be evaluated more than once");
         }
 
-        return evaluator.evaluate(attributes);
+        return evaluator.evaluate(registry.getVariables());
     }
 
     Tree getTree() {

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/StandardAttributeExpression.java

@@ -20,13 +20,17 @@ import org.apache.nifi.expression.AttributeExpression;
 import org.apache.nifi.expression.AttributeValueDecorator;
 import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 
 public class StandardAttributeExpression implements AttributeExpression {
 
     private final Query query;
+    private final VariableRegistry variableRegistry;
 
-    public StandardAttributeExpression(final Query query) {
+    public StandardAttributeExpression(final Query query, final VariableRegistry variableRegistry) {
         this.query = query;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -51,7 +55,8 @@ public class StandardAttributeExpression implements AttributeExpression {
 
     @Override
     public String evaluate(final FlowFile flowFile, final AttributeValueDecorator decorator) throws ProcessException {
-        final Object evaluationResult = query.evaluate(flowFile).getValue();
+        VariableRegistry flowFileRegistry = VariableRegistryUtils.createFlowVariableRegistry(variableRegistry,flowFile,null);
+        final Object evaluationResult = query.evaluate(flowFileRegistry).getValue();
         if (evaluationResult == null) {
             return "";
         }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/StandardExpressionLanguageCompiler.java

@@ -20,13 +20,20 @@ import org.apache.nifi.attribute.expression.language.exception.AttributeExpressi
 import org.apache.nifi.expression.AttributeExpression;
 import org.apache.nifi.expression.ExpressionLanguageCompiler;
 import org.apache.nifi.expression.AttributeExpression.ResultType;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class StandardExpressionLanguageCompiler implements ExpressionLanguageCompiler {
 
+    private final VariableRegistry variableRegistry;
+
+    public StandardExpressionLanguageCompiler(final VariableRegistry variableRegistry) {
+        this.variableRegistry = variableRegistry;
+    }
+
     @Override
     public AttributeExpression compile(final String expression) throws IllegalArgumentException {
         try {
-            return new StandardAttributeExpression(Query.compile(expression));
+            return new StandardAttributeExpression(Query.compile(expression),variableRegistry);
         } catch (final AttributeExpressionLanguageParsingException e) {
             throw new IllegalArgumentException(e.getMessage());
         }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/StandardPreparedQuery.java

@@ -22,10 +22,10 @@ import java.util.List;
 import java.util.Map;
 
 import org.apache.nifi.expression.AttributeValueDecorator;
-import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.exception.ProcessException;
 
 import org.antlr.runtime.tree.Tree;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class StandardPreparedQuery implements PreparedQuery {
 
@@ -37,20 +37,16 @@ public class StandardPreparedQuery implements PreparedQuery {
         this.trees = new HashMap<>(trees);
     }
 
-    @Override
-    public String evaluateExpressions(Map<String, String> attributes) throws ProcessException {
-        return evaluateExpressions(attributes, null);
-    }
 
     @Override
-    public String evaluateExpressions(final Map<String, String> attributes, final AttributeValueDecorator decorator) throws ProcessException {
+    public String evaluateExpressions(final VariableRegistry registry, final AttributeValueDecorator decorator) throws ProcessException {
         final StringBuilder sb = new StringBuilder();
         for (final String val : queryStrings) {
             final Tree tree = trees.get(val);
             if (tree == null) {
                 sb.append(val);
             } else {
-                final String evaluated = Query.evaluateExpression(tree, val, attributes, decorator);
+                final String evaluated = Query.evaluateExpression(tree, val, registry, decorator);
                 if (evaluated != null) {
                     sb.append(evaluated);
                 }
@@ -59,31 +55,4 @@ public class StandardPreparedQuery implements PreparedQuery {
         return sb.toString();
     }
 
-    @Override
-    public String evaluateExpressions(final FlowFile flowFile, final Map<String, String> additionalAttributes, final AttributeValueDecorator decorator) throws ProcessException {
-        final Map<String, String> expressionMap = Query.createExpressionMap(flowFile, additionalAttributes);
-        return evaluateExpressions(expressionMap, decorator);
-    }
-
-    @Override
-    public String evaluateExpressions(final FlowFile flowFile, final AttributeValueDecorator decorator) throws ProcessException {
-        final Map<String, String> expressionMap = Query.createExpressionMap(flowFile);
-        return evaluateExpressions(expressionMap, decorator);
-    }
-
-    @Override
-    public String evaluateExpressions() throws ProcessException {
-        return evaluateExpressions((FlowFile) null, null);
-    }
-
-    @Override
-    public String evaluateExpressions(final AttributeValueDecorator decorator) throws ProcessException {
-        return evaluateExpressions((FlowFile) null, decorator);
-    }
-
-    @Override
-    public String evaluateExpressions(final FlowFile flowFile) throws ProcessException {
-        return evaluateExpressions(flowFile, null);
-    }
-
 }

nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/StandardPropertyValue.java

@@ -26,6 +26,8 @@ import org.apache.nifi.expression.AttributeValueDecorator;
 import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.DataUnit;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.FormatUtils;
 
 public class StandardPropertyValue implements PropertyValue {
@@ -33,24 +35,27 @@ public class StandardPropertyValue implements PropertyValue {
     private final String rawValue;
     private final ControllerServiceLookup serviceLookup;
     private final PreparedQuery preparedQuery;
+    private final VariableRegistry variableRegistry;
 
-    public StandardPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup) {
+    public StandardPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final VariableRegistry variableRegistry) {
-        this(rawValue, serviceLookup, Query.prepare(rawValue));
+        this(rawValue, serviceLookup, Query.prepare(rawValue), variableRegistry);
     }
 
     /**
      * Constructs a new StandardPropertyValue with the given value & service lookup and indicates whether or not the rawValue contains any NiFi Expressions. If it is unknown whether or not the value
-     * contains any NiFi Expressions, the {@link #StandardPropertyValue(String, ControllerServiceLookup)} constructor should be used or <code>true</code> should be passed. However, if it is known that
+     * contains any NiFi Expressions, the {@link #StandardPropertyValue(String, ControllerServiceLookup, VariableRegistry)} constructor should be used or <code>true</code> should be passed.
-     * the value contains no NiFi Expression, that information should be provided so that calls to {@link #evaluateAttributeExpressions()} are much more efficient
+     * However, if it is known that the value contains no NiFi Expression, that information should be provided so that calls to {@link #evaluateAttributeExpressions()} are much more efficient
-     *
      * @param rawValue value
      * @param serviceLookup lookup
      * @param preparedQuery query
+     * @param variableRegistry variableRegistry
      */
-    public StandardPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final PreparedQuery preparedQuery) {
+    public StandardPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final PreparedQuery preparedQuery,
+                                 final VariableRegistry variableRegistry) {
         this.rawValue = rawValue;
         this.serviceLookup = serviceLookup;
         this.preparedQuery = preparedQuery;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -133,10 +138,12 @@ public class StandardPropertyValue implements PropertyValue {
         if (rawValue == null || preparedQuery == null) {
             return this;
         }
-
+        VariableRegistry registry = VariableRegistryUtils.createFlowVariableRegistry(variableRegistry,flowFile,additionalAttributes);
-        return new StandardPropertyValue(preparedQuery.evaluateExpressions(flowFile, additionalAttributes, decorator), serviceLookup, null);
+        return new StandardPropertyValue(preparedQuery.evaluateExpressions(registry,decorator), serviceLookup,null,registry);
     }
 
+
+
     @Override
     public String toString() {
         return rawValue;

nifi-commons/nifi-expression-language/src/test/groovy/org/apache/nifi/attribute/expression/language/QueryGroovyTest.groovy

@@ -18,6 +18,8 @@ package org.apache.nifi.attribute.expression.language
 
 import org.apache.nifi.attribute.expression.language.evaluation.QueryResult
 import org.apache.nifi.expression.AttributeExpression
+import org.apache.nifi.registry.VariableRegistry
+import org.apache.nifi.registry.VariableRegistryFactory
 import org.junit.After
 import org.junit.Before
 import org.junit.BeforeClass
@@ -57,6 +59,7 @@ public class QueryGroovyTest extends GroovyTestCase {
         final Map<String, String> attributes = [
                 single   : ORIGINAL_VALUE,
                 repeating: [ORIGINAL_VALUE].multiply(n).join(" ")]
+        final VariableRegistry variableRegistry = VariableRegistryFactory.getInstance(attributes)
         logger.info("Attributes: ${attributes}")
 
         final String REPLACEMENT_VALUE = "Goodbye Planet"
@@ -75,10 +78,10 @@ public class QueryGroovyTest extends GroovyTestCase {
         Query replaceRepeatingQuery = Query.compile(REPLACE_REPEATING_EXPRESSION)
 
         // Act
-        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(attributes)
+        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(variableRegistry)
         logger.info("Replace single result: ${replaceSingleResult.value}")
 
-        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(attributes)
+        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(variableRegistry)
         logger.info("Replace repeating result: ${replaceRepeatingResult.value}")
 
         // Assert
@@ -97,6 +100,7 @@ public class QueryGroovyTest extends GroovyTestCase {
         final Map<String, String> attributes = [
                 single   : ORIGINAL_VALUE,
                 repeating: [ORIGINAL_VALUE].multiply(n).join(" ")]
+        final VariableRegistry variableRegistry = VariableRegistryFactory.getInstance(attributes)
         logger.info("Attributes: ${attributes}")
 
         final String REPLACEMENT_VALUE = "Goodbye Planet"
@@ -115,10 +119,10 @@ public class QueryGroovyTest extends GroovyTestCase {
         Query replaceRepeatingQuery = Query.compile(REPLACE_REPEATING_EXPRESSION)
 
         // Act
-        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(attributes)
+        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(variableRegistry)
         logger.info("Replace single result: ${replaceSingleResult.value}")
 
-        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(attributes)
+        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(variableRegistry)
         logger.info("Replace repeating result: ${replaceRepeatingResult.value}")
 
         // Assert
@@ -137,6 +141,7 @@ public class QueryGroovyTest extends GroovyTestCase {
         final Map<String, String> attributes = [
                 single   : ORIGINAL_VALUE,
                 repeating: [ORIGINAL_VALUE].multiply(n).join(" ")]
+        final VariableRegistry variableRegistry = VariableRegistryFactory.getInstance(attributes)
         logger.info("Attributes: ${attributes}")
 
         final String REPLACEMENT_VALUE = "Goodbye Planet"
@@ -155,10 +160,10 @@ public class QueryGroovyTest extends GroovyTestCase {
         Query replaceRepeatingQuery = Query.compile(REPLACE_REPEATING_EXPRESSION)
 
         // Act
-        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(attributes)
+        QueryResult<?> replaceSingleResult = replaceSingleQuery.evaluate(variableRegistry)
         logger.info("Replace single result: ${replaceSingleResult.value}")
 
-        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(attributes)
+        QueryResult<?> replaceRepeatingResult = replaceRepeatingQuery.evaluate(variableRegistry)
         logger.info("Replace repeating result: ${replaceRepeatingResult.value}")
 
         // Assert

nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestQuery.java

@@ -35,6 +35,7 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Properties;
 
 import org.apache.nifi.attribute.expression.language.Query.Range;
 import org.apache.nifi.attribute.expression.language.evaluation.QueryResult;
@@ -43,7 +44,12 @@ import org.apache.nifi.attribute.expression.language.exception.AttributeExpressi
 import org.apache.nifi.expression.AttributeExpression.ResultType;
 import org.apache.nifi.flowfile.FlowFile;
 import org.antlr.runtime.tree.Tree;
+
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryFactory;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.Assert;
+
 import org.junit.Ignore;
 import org.junit.Test;
 
@@ -51,6 +57,7 @@ import org.mockito.Mockito;
 
 public class TestQuery {
 
+
     @Test
     public void testCompilation() {
         assertInvalid("${attr:uuid()}");
@@ -114,7 +121,7 @@ public class TestQuery {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("x", "x");
         attributes.put("y", "x");
-        final String result = Query.evaluateExpressions(expression, attributes, null);
+        final String result = Query.evaluateExpressions(expression,VariableRegistryFactory.getInstance(attributes), null);
         assertEquals("true", result);
 
         Query.validateExpression(expression, false);
@@ -174,14 +181,14 @@ public class TestQuery {
     public void testWithTicksOutside() {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("attr", "My Value");
-
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
         assertEquals(1, Query.extractExpressionRanges("\"${attr}").size());
         assertEquals(1, Query.extractExpressionRanges("'${attr}").size());
         assertEquals(1, Query.extractExpressionRanges("'${attr}'").size());
         assertEquals(1, Query.extractExpressionRanges("${attr}").size());
 
-        assertEquals("'My Value'", Query.evaluateExpressions("'${attr}'", attributes, null));
+        assertEquals("'My Value'", Query.evaluateExpressions("'${attr}'", registry, null));
-        assertEquals("'My Value", Query.evaluateExpressions("'${attr}", attributes, null));
+        assertEquals("'My Value", Query.evaluateExpressions("'${attr}", registry, null));
     }
 
     @Test
@@ -191,7 +198,7 @@ public class TestQuery {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("dateTime", "2013/11/18 10:22:27.678");
 
-        final QueryResult<?> result = query.evaluate(attributes);
+        final QueryResult<?> result = query.evaluate(VariableRegistryFactory.getInstance(attributes));
         assertEquals(ResultType.NUMBER, result.getResultType());
         assertEquals(1384788147678L, result.getValue());
     }
@@ -220,7 +227,7 @@ public class TestQuery {
         final Date roundedToNearestSecond = new Date(date.getTime() - millis);
         final String formatted = sdf.format(roundedToNearestSecond);
 
-        final QueryResult<?> result = query.evaluate(attributes);
+        final QueryResult<?> result = query.evaluate(VariableRegistryFactory.getInstance(attributes));
         assertEquals(ResultType.STRING, result.getResultType());
         assertEquals(formatted, result.getValue());
     }
@@ -230,14 +237,15 @@ public class TestQuery {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("x", "abc");
         attributes.put("a", "abc");
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
 
         verifyEquals("${x:equals(${a})}", attributes, true);
 
         Query.validateExpression("${x:equals('${a}')}", false);
-        assertEquals("true", Query.evaluateExpressions("${x:equals('${a}')}", attributes, null));
+        assertEquals("true", Query.evaluateExpressions("${x:equals('${a}')}", registry, null));
 
         Query.validateExpression("${x:equals(\"${a}\")}", false);
-        assertEquals("true", Query.evaluateExpressions("${x:equals(\"${a}\")}", attributes, null));
+        assertEquals("true", Query.evaluateExpressions("${x:equals(\"${a}\")}", registry, null));
     }
 
     @Test
@@ -268,6 +276,22 @@ public class TestQuery {
         }
     }
 
+    @Test
+    public void testEmbeddedExpressionsAndQuotesWithProperties() {
+        final Properties attributes = new Properties();
+        attributes.put("x", "abc");
+        attributes.put("a", "abc");
+        VariableRegistry registry = VariableRegistryFactory.getPropertiesInstance(attributes);
+
+        verifyEquals("${x:equals(${a})}",registry,true);
+
+        Query.validateExpression("${x:equals('${a}')}", false);
+        assertEquals("true", Query.evaluateExpressions("${x:equals('${a}')}", registry, null));
+
+        Query.validateExpression("${x:equals(\"${a}\")}", false);
+        assertEquals("true", Query.evaluateExpressions("${x:equals(\"${a}\")}", registry, null));
+    }
+
     @Test
     public void testJoin() {
         final Map<String, String> attributes = new HashMap<>();
@@ -342,7 +366,9 @@ public class TestQuery {
         Mockito.when(mockFlowFile.getEntryDate()).thenReturn(System.currentTimeMillis());
         Mockito.when(mockFlowFile.getSize()).thenReturn(1L);
         Mockito.when(mockFlowFile.getLineageStartDate()).thenReturn(System.currentTimeMillis());
-        return Query.evaluateExpressions(queryString, mockFlowFile);
+
+        final VariableRegistry variableRegistry = VariableRegistryUtils.createFlowVariableRegistry(VariableRegistryUtils.createSystemVariableRegistry(),mockFlowFile,null);
+        return Query.evaluateExpressions(queryString,variableRegistry);
     }
 
     @Test
@@ -498,7 +524,7 @@ public class TestQuery {
         verifyEquals("${x:toNumber():gt( ${y:toNumber():plus( ${z:toNumber()} )} )}", attributes, true);
 
         attributes.put("y", "88");
-        assertEquals("true", Query.evaluateExpressions("${x:equals( '${y}' )}", attributes, null));
+        assertEquals("true", Query.evaluateExpressions("${x:equals( '${y}' )}", VariableRegistryFactory.getInstance(attributes), null));
     }
 
     @Test
@@ -546,7 +572,7 @@ public class TestQuery {
         final String format = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
 
         final String query = "startDateTime=\"${date:toNumber():toDate():format(\"" + format + "\")}\"";
-        final String result = Query.evaluateExpressions(query, attributes, null);
+        final String result = Query.evaluateExpressions(query, VariableRegistryFactory.getInstance(attributes), null);
 
         final String expectedTime = new SimpleDateFormat(format, Locale.US).format(timestamp);
         assertEquals("startDateTime=\"" + expectedTime + "\"", result);
@@ -615,7 +641,7 @@ public class TestQuery {
         final String query = "${ abc:equals('abc'):or( \n\t${xx:isNull()}\n) }";
         assertEquals(ResultType.BOOLEAN, Query.getResultType(query));
         Query.validateExpression(query, false);
-        assertEquals("true", Query.evaluateExpressions(query));
+        assertEquals("true", Query.evaluateExpressions(query,VariableRegistryUtils.createSystemVariableRegistry()));
     }
 
     @Test
@@ -631,7 +657,7 @@ public class TestQuery {
     public void testComments() {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("abc", "xyz");
-
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
         final String expression
         = "# hello, world\n"
             + "${# ref attr\n"
@@ -642,12 +668,12 @@ public class TestQuery {
             + "}";
 
         Query query = Query.compile(expression);
-        QueryResult<?> result = query.evaluate(attributes);
+        QueryResult<?> result = query.evaluate(registry);
         assertEquals(ResultType.STRING, result.getResultType());
         assertEquals("xyz", result.getValue());
 
         query = Query.compile("${abc:append('# hello') #good-bye \n}");
-        result = query.evaluate(attributes);
+        result = query.evaluate(registry);
         assertEquals(ResultType.STRING, result.getResultType());
         assertEquals("xyz# hello", result.getValue());
     }
@@ -776,14 +802,15 @@ public class TestQuery {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("entryDate", String.valueOf(now.getTimeInMillis()));
 
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
         verifyEquals("${entryDate:toNumber():toDate():format('yyyy')}", attributes, String.valueOf(year));
 
         attributes.clear();
         attributes.put("month", "3");
         attributes.put("day", "4");
         attributes.put("year", "2013");
-        assertEquals("63", Query.evaluateExpressions("${year:append('/'):append(${month}):append('/'):append(${day}):toDate('yyyy/MM/dd'):format('D')}", attributes, null));
+        assertEquals("63", Query.evaluateExpressions("${year:append('/'):append(${month}):append('/'):append(${day}):toDate('yyyy/MM/dd'):format('D')}", registry, null));
-        assertEquals("63", Query.evaluateExpressions("${year:append('/'):append('${month}'):append('/'):append('${day}'):toDate('yyyy/MM/dd'):format('D')}", attributes, null));
+        assertEquals("63", Query.evaluateExpressions("${year:append('/'):append('${month}'):append('/'):append('${day}'):toDate('yyyy/MM/dd'):format('D')}", registry, null));
 
         verifyEquals("${year:append('/'):append(${month}):append('/'):append(${day}):toDate('yyyy/MM/dd'):format('D')}", attributes, "63");
     }
@@ -791,8 +818,9 @@ public class TestQuery {
     @Test
     public void testSystemProperty() {
         System.setProperty("hello", "good-bye");
-        assertEquals("good-bye", Query.evaluateExpressions("${hello}"));
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
-        assertEquals("good-bye", Query.compile("${hello}").evaluate().getValue());
+        assertEquals("good-bye", Query.evaluateExpressions("${hello}",variableRegistry));
+        assertEquals("good-bye", Query.compile("${hello}").evaluate(variableRegistry).getValue());
     }
 
     @Test
@@ -832,14 +860,15 @@ public class TestQuery {
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("abc", "a,b,c");
         attributes.put("xyz", "abc");
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
 
         final String query = "${anyDelineatedValue('${abc}', ','):equals('b')}";
         assertEquals(ResultType.BOOLEAN, Query.getResultType(query));
 
-        assertEquals("true", Query.evaluateExpressions(query, attributes, null));
+        assertEquals("true", Query.evaluateExpressions(query, registry, null));
-        assertEquals("true", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('a')}", attributes, null));
+        assertEquals("true", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('a')}", registry, null));
-        assertEquals("true", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('c')}", attributes, null));
+        assertEquals("true", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('c')}", registry, null));
-        assertEquals("false", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('d')}", attributes, null));
+        assertEquals("false", Query.evaluateExpressions("${anyDelineatedValue('${abc}', ','):equals('d')}", registry, null));
 
         verifyEquals("${anyDelineatedValue(${abc}, ','):equals('b')}", attributes, true);
         verifyEquals("${anyDelineatedValue(${abc}, ','):equals('a')}", attributes, true);
@@ -853,13 +882,15 @@ public class TestQuery {
         attributes.put("abc", "a,b,c");
         attributes.put("xyz", "abc");
 
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
+
         final String query = "${allDelineatedValues('${abc}', ','):matches('[abc]')}";
 
         assertEquals(ResultType.BOOLEAN, Query.getResultType(query));
-        assertEquals("true", Query.evaluateExpressions(query, attributes, null));
+        assertEquals("true", Query.evaluateExpressions(query, registry, null));
-        assertEquals("true", Query.evaluateExpressions(query, attributes, null));
+        assertEquals("true", Query.evaluateExpressions(query, registry, null));
-        assertEquals("false", Query.evaluateExpressions("${allDelineatedValues('${abc}', ','):matches('[abd]')}", attributes, null));
+        assertEquals("false", Query.evaluateExpressions("${allDelineatedValues('${abc}', ','):matches('[abd]')}",registry, null));
-        assertEquals("false", Query.evaluateExpressions("${allDelineatedValues('${abc}', ','):equals('a'):not()}", attributes, null));
+        assertEquals("false", Query.evaluateExpressions("${allDelineatedValues('${abc}', ','):equals('a'):not()}", registry, null));
 
         verifyEquals("${allDelineatedValues(${abc}, ','):matches('[abc]')}", attributes, true);
         verifyEquals("${allDelineatedValues(${abc}, ','):matches('[abd]')}", attributes, false);
@@ -925,12 +956,13 @@ public class TestQuery {
         attributes.put("xyz", "4132");
         attributes.put("hello", "world!");
         attributes.put("dotted", "abc.xyz");
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
 
-        final String evaluated = Query.evaluateExpressions("${abc:matches('1234${end}4321')}", attributes, null);
+        final String evaluated = Query.evaluateExpressions("${abc:matches('1234${end}4321')}", registry, null);
         assertEquals("true", evaluated);
 
         attributes.put("end", "888");
-        final String secondEvaluation = Query.evaluateExpressions("${abc:matches('1234${end}4321')}", attributes, null);
+        final String secondEvaluation = Query.evaluateExpressions("${abc:matches('1234${end}4321')}", registry, null);
         assertEquals("false", secondEvaluation);
 
         verifyEquals("${dotted:matches('abc\\.xyz')}", attributes, true);
@@ -945,11 +977,13 @@ public class TestQuery {
         attributes.put("hello", "world!");
         attributes.put("dotted", "abc.xyz");
 
-        final String evaluated = Query.evaluateExpressions("${abc:find('1234${end}4321')}", attributes, null);
+        final String evaluated = Query.evaluateExpressions("${abc:find('1234${end}4321')}", VariableRegistryFactory.getInstance(attributes), null);
         assertEquals("true", evaluated);
 
         attributes.put("end", "888");
-        final String secondEvaluation = Query.evaluateExpressions("${abc:find('${end}4321')}", attributes, null);
+
+
+        final String secondEvaluation = Query.evaluateExpressions("${abc:find('${end}4321')}",VariableRegistryFactory.getInstance(attributes), null);
         assertEquals("false", secondEvaluation);
 
         verifyEquals("${dotted:find('\\.')}", attributes, true);
@@ -1130,7 +1164,7 @@ public class TestQuery {
         attributes.put("b", "x");
         attributes.put("abcxcba", "hello");
 
-        final String evaluated = Query.evaluateExpressions("${ 'abc${b}cba':substring(0, 1) }", attributes, null);
+        final String evaluated = Query.evaluateExpressions("${ 'abc${b}cba':substring(0, 1) }", VariableRegistryFactory.getInstance(attributes), null);
         assertEquals("h", evaluated);
     }
 
@@ -1164,7 +1198,7 @@ public class TestQuery {
         final List<String> expressions = Query.extractExpressions(query);
         assertEquals(1, expressions.size());
         assertEquals("${abc}", expressions.get(0));
-        assertEquals("{ xyz }", Query.evaluateExpressions(query, attributes));
+        assertEquals("{ xyz }", Query.evaluateExpressions(query, VariableRegistryFactory.getInstance(attributes)));
     }
 
     @Test
@@ -1188,7 +1222,7 @@ public class TestQuery {
 
     QueryResult<?> getResult(String expr, Map<String, String> attrs) {
         final Query query = Query.compile(expr);
-        final QueryResult<?> result = query.evaluate(attrs);
+        final QueryResult<?> result = query.evaluate(VariableRegistryFactory.getInstance(attrs));
         return result;
     }
 
@@ -1297,11 +1331,17 @@ public class TestQuery {
     }
 
     private void verifyEquals(final String expression, final Map<String, String> attributes, final Object expectedResult) {
+
+        VariableRegistry registry = VariableRegistryFactory.getInstance(attributes);
+        verifyEquals(expression,registry,expectedResult);
+    }
+
+    private void verifyEquals(final String expression, final VariableRegistry registry, final Object expectedResult) {
         Query.validateExpression(expression, false);
-        assertEquals(String.valueOf(expectedResult), Query.evaluateExpressions(expression, attributes, null));
+        assertEquals(String.valueOf(expectedResult), Query.evaluateExpressions(expression, registry, null));
 
         final Query query = Query.compile(expression);
-        final QueryResult<?> result = query.evaluate(attributes);
+        final QueryResult<?> result = query.evaluate(registry);
 
         if (expectedResult instanceof Number) {
             assertEquals(ResultType.NUMBER, result.getResultType());

nifi-commons/nifi-expression-language/src/test/java/org/apache/nifi/attribute/expression/language/TestStandardPreparedQuery.java

@@ -22,6 +22,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
+import org.apache.nifi.registry.VariableRegistryFactory;
 import org.junit.Ignore;
 import org.junit.Test;
 
@@ -53,7 +54,7 @@ public class TestStandardPreparedQuery {
         final StandardPreparedQuery prepared = (StandardPreparedQuery) Query.prepare("${xx}");
         final long start = System.nanoTime();
         for (int i = 0; i < 10000000; i++) {
-            assertEquals("world", prepared.evaluateExpressions(attrs, null));
+            assertEquals("world", prepared.evaluateExpressions(VariableRegistryFactory.getInstance(attrs), null));
         }
         final long nanos = System.nanoTime() - start;
         System.out.println(TimeUnit.NANOSECONDS.toMillis(nanos));
@@ -67,7 +68,7 @@ public class TestStandardPreparedQuery {
 
         final long start = System.nanoTime();
         for (int i = 0; i < 10000000; i++) {
-            assertEquals("world", Query.evaluateExpressions("${xx}", attrs));
+            assertEquals("world", Query.evaluateExpressions("${xx}", VariableRegistryFactory.getInstance(attrs)));
         }
         final long nanos = System.nanoTime() - start;
         System.out.println(TimeUnit.NANOSECONDS.toMillis(nanos));
@@ -85,7 +86,7 @@ public class TestStandardPreparedQuery {
     }
 
     private String evaluate(final String query, final Map<String, String> attrs) {
-        final String evaluated = ((StandardPreparedQuery) Query.prepare(query)).evaluateExpressions(attrs, null);
+        final String evaluated = ((StandardPreparedQuery) Query.prepare(query)).evaluateExpressions(VariableRegistryFactory.getInstance(attrs), null);
         return evaluated;
     }
 

nifi-commons/nifi-properties/src/main/java/org/apache/nifi/util/NiFiProperties.java

@@ -28,6 +28,7 @@ import java.nio.file.InvalidPathException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -188,6 +189,9 @@ public class NiFiProperties extends Properties {
     public static final String STATE_MANAGEMENT_START_EMBEDDED_ZOOKEEPER = "nifi.state.management.embedded.zookeeper.start";
     public static final String STATE_MANAGEMENT_ZOOKEEPER_PROPERTIES = "nifi.state.management.embedded.zookeeper.properties";
 
+    // expression language properties
+    public static final String VARIABLE_REGISTRY_PROPERTIES = "nifi.variable.registry.properties";
+
     // defaults
     public static final String DEFAULT_TITLE = "NiFi";
     public static final Boolean DEFAULT_AUTO_RESUME_STATE = true;
@@ -963,4 +967,27 @@ public class NiFiProperties extends Properties {
     public String getFlowConfigurationArchiveMaxStorage() {
         return getProperty(FLOW_CONFIGURATION_ARCHIVE_MAX_STORAGE, DEFAULT_FLOW_CONFIGURATION_ARCHIVE_MAX_STORAGE);
     }
+
+    public String getVariableRegistryProperties(){
+        return getProperty(VARIABLE_REGISTRY_PROPERTIES);
+    }
+
+    public Path[] getVariableRegistryPropertiesPaths() {
+        final List<Path> vrPropertiesPaths = new ArrayList<>();
+
+        final String vrPropertiesFiles = getVariableRegistryProperties();
+        if(!StringUtils.isEmpty(vrPropertiesFiles)) {
+
+            final List<String> vrPropertiesFileList = Arrays.asList(vrPropertiesFiles.split(","));
+
+            for(String propertiesFile : vrPropertiesFileList){
+                vrPropertiesPaths.add(Paths.get(propertiesFile));
+            }
+
+            return vrPropertiesPaths.toArray( new Path[vrPropertiesPaths.size()]);
+        } else {
+            return null;
+        }
+    }
+
 }

nifi-framework-api/src/main/java/org/apache/nifi/web/NiFiWebConfigurationContext.java

@@ -16,16 +16,17 @@
  */
 package org.apache.nifi.web;
 
-import org.apache.nifi.controller.ControllerService;
-
 import java.util.Collection;
 import java.util.Map;
 
+import org.apache.nifi.controller.ControllerService;
+import org.apache.nifi.registry.VariableRegistryProvider;
+
 /**
  * NiFi web context providing limited access to dataflow configuration for
  * component custom UIs.
  */
-public interface NiFiWebConfigurationContext {
+public interface NiFiWebConfigurationContext extends VariableRegistryProvider {
 
     /**
      * @param serviceIdentifier of the controller service

nifi-mock/src/main/java/org/apache/nifi/util/MockConfigurationContext.java

@@ -25,21 +25,26 @@ import org.apache.nifi.components.PropertyValue;
 import org.apache.nifi.controller.ConfigurationContext;
 import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.ControllerServiceLookup;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class MockConfigurationContext implements ConfigurationContext {
 
     private final Map<PropertyDescriptor, String> properties;
     private final ControllerServiceLookup serviceLookup;
     private final ControllerService service;
+    private final VariableRegistry variableRegistry;
 
-    public MockConfigurationContext(final Map<PropertyDescriptor, String> properties, final ControllerServiceLookup serviceLookup) {
+    public MockConfigurationContext(final Map<PropertyDescriptor, String> properties, final ControllerServiceLookup serviceLookup,
-        this(null, properties, serviceLookup);
+                                    final VariableRegistry variableRegistry) {
+        this(null, properties, serviceLookup, variableRegistry);
     }
 
-    public MockConfigurationContext(final ControllerService service, final Map<PropertyDescriptor, String> properties, final ControllerServiceLookup serviceLookup) {
+    public MockConfigurationContext(final ControllerService service, final Map<PropertyDescriptor, String> properties, final ControllerServiceLookup serviceLookup,
+                                    final VariableRegistry variableRegistry) {
         this.service = service;
         this.properties = properties;
         this.serviceLookup = serviceLookup;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -48,7 +53,7 @@ public class MockConfigurationContext implements ConfigurationContext {
         if (value == null) {
             value = getActualDescriptor(property).getDefaultValue();
         }
-        return new MockPropertyValue(value, serviceLookup);
+        return new MockPropertyValue(value, serviceLookup, variableRegistry);
     }
 
     @Override

nifi-mock/src/main/java/org/apache/nifi/util/MockProcessContext.java

@@ -40,6 +40,7 @@ import org.apache.nifi.controller.NodeTypeProvider;
 import org.apache.nifi.processor.Processor;
 import org.apache.nifi.processor.Relationship;
 import org.apache.nifi.processor.SchedulingContext;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.state.MockStateManager;
 import org.junit.Assert;
 
@@ -48,6 +49,7 @@ public class MockProcessContext extends MockControllerServiceLookup implements S
     private final ConfigurableComponent component;
     private final Map<PropertyDescriptor, String> properties = new HashMap<>();
     private final StateManager stateManager;
+    private final VariableRegistry variableRegistry;
 
     private String annotationData = null;
     private boolean yieldCalled = false;
@@ -63,22 +65,24 @@ public class MockProcessContext extends MockControllerServiceLookup implements S
     private volatile boolean isClustered;
     private volatile boolean isPrimaryNode;
 
-    public MockProcessContext(final ConfigurableComponent component) {
+    public MockProcessContext(final ConfigurableComponent component, final VariableRegistry variableRegistry) {
-        this(component, new MockStateManager(component));
+        this(component, new MockStateManager(component),variableRegistry);
     }
 
     /**
      * Creates a new MockProcessContext for the given Processor
      *
      * @param component being mocked
+     * @param variableRegistry variableRegistry
      */
-    public MockProcessContext(final ConfigurableComponent component, final StateManager stateManager) {
+    public MockProcessContext(final ConfigurableComponent component, final StateManager stateManager, final VariableRegistry variableRegistry) {
         this.component = Objects.requireNonNull(component);
         this.stateManager = stateManager;
+        this.variableRegistry = variableRegistry;
     }
 
-    public MockProcessContext(final ControllerService component, final MockProcessContext context, final StateManager stateManager) {
+    public MockProcessContext(final ControllerService component, final MockProcessContext context, final StateManager stateManager, final VariableRegistry variableRegistry) {
-        this(component, stateManager);
+        this(component, stateManager, variableRegistry);
 
         try {
             annotationData = context.getControllerServiceAnnotationData(component);
@@ -105,12 +109,13 @@ public class MockProcessContext extends MockControllerServiceLookup implements S
 
         final String setPropertyValue = properties.get(descriptor);
         final String propValue = (setPropertyValue == null) ? descriptor.getDefaultValue() : setPropertyValue;
-        return new MockPropertyValue(propValue, this, (enableExpressionValidation && allowExpressionValidation) ? descriptor : null);
+
+        return new MockPropertyValue(propValue, this, variableRegistry, (enableExpressionValidation && allowExpressionValidation) ? descriptor : null);
     }
 
     @Override
     public PropertyValue newPropertyValue(final String rawValue) {
-        return new MockPropertyValue(rawValue, this);
+        return new MockPropertyValue(rawValue, this, variableRegistry);
     }
 
     public ValidationResult setProperty(final String propertyName, final String propertyValue) {
@@ -133,7 +138,7 @@ public class MockProcessContext extends MockControllerServiceLookup implements S
         requireNonNull(value, "Cannot set property to null value; if the intent is to remove the property, call removeProperty instead");
         final PropertyDescriptor fullyPopulatedDescriptor = component.getPropertyDescriptor(descriptor.getName());
 
-        final ValidationResult result = fullyPopulatedDescriptor.validate(value, new MockValidationContext(this, stateManager));
+        final ValidationResult result = fullyPopulatedDescriptor.validate(value, new MockValidationContext(this, stateManager, variableRegistry));
         String oldValue = properties.put(fullyPopulatedDescriptor, value);
         if (oldValue == null) {
             oldValue = fullyPopulatedDescriptor.getDefaultValue();
@@ -216,7 +221,7 @@ public class MockProcessContext extends MockControllerServiceLookup implements S
      * non-null
      */
     public Collection<ValidationResult> validate() {
-        return component.validate(new MockValidationContext(this, stateManager));
+        return component.validate(new MockValidationContext(this, stateManager, variableRegistry));
     }
 
     public boolean isValid() {

nifi-mock/src/main/java/org/apache/nifi/util/MockPropertyValue.java

@@ -28,6 +28,7 @@ import org.apache.nifi.expression.AttributeValueDecorator;
 import org.apache.nifi.flowfile.FlowFile;
 import org.apache.nifi.processor.DataUnit;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class MockPropertyValue implements PropertyValue {
     private final String rawValue;
@@ -35,24 +36,27 @@ public class MockPropertyValue implements PropertyValue {
     private final ControllerServiceLookup serviceLookup;
     private final PropertyDescriptor propertyDescriptor;
     private final PropertyValue stdPropValue;
+    private final VariableRegistry variableRegistry;
     private boolean expressionsEvaluated = false;
 
-    public MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup) {
+    public MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final VariableRegistry variableRegistry) {
-        this(rawValue, serviceLookup, null);
+        this(rawValue, serviceLookup, variableRegistry, null);
     }
 
-    public MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final PropertyDescriptor propertyDescriptor) {
+    public MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, VariableRegistry variableRegistry, final PropertyDescriptor propertyDescriptor) {
-        this(rawValue, serviceLookup, propertyDescriptor, false);
+        this(rawValue, serviceLookup, propertyDescriptor, false, variableRegistry);
     }
 
-    private MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final PropertyDescriptor propertyDescriptor, final boolean alreadyEvaluated) {
+    private MockPropertyValue(final String rawValue, final ControllerServiceLookup serviceLookup, final PropertyDescriptor propertyDescriptor, final boolean alreadyEvaluated,
-        this.stdPropValue = new StandardPropertyValue(rawValue, serviceLookup);
+                              final VariableRegistry variableRegistry) {
+        this.stdPropValue = new StandardPropertyValue(rawValue, serviceLookup, variableRegistry);
 
         this.rawValue = rawValue;
         this.serviceLookup = serviceLookup;
         this.expectExpressions = propertyDescriptor == null ? null : propertyDescriptor.isExpressionLanguageSupported();
         this.propertyDescriptor = propertyDescriptor;
         this.expressionsEvaluated = alreadyEvaluated;
+        this.variableRegistry = variableRegistry;
     }
 
 
@@ -165,7 +169,7 @@ public class MockPropertyValue implements PropertyValue {
         }
 
         final PropertyValue newValue = stdPropValue.evaluateAttributeExpressions(flowFile, additionalAttributes, decorator);
-        return new MockPropertyValue(newValue.getValue(), serviceLookup, propertyDescriptor, true);
+        return new MockPropertyValue(newValue.getValue(), serviceLookup, propertyDescriptor, true, variableRegistry);
     }
 
     @Override

nifi-mock/src/main/java/org/apache/nifi/util/MockReportingContext.java

@@ -27,6 +27,7 @@ import org.apache.nifi.components.PropertyValue;
 import org.apache.nifi.components.state.StateManager;
 import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.ControllerServiceLookup;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.Bulletin;
 import org.apache.nifi.reporting.BulletinFactory;
 import org.apache.nifi.reporting.BulletinRepository;
@@ -39,12 +40,14 @@ public class MockReportingContext extends MockControllerServiceLookup implements
     private final MockEventAccess eventAccess = new MockEventAccess();
     private final Map<PropertyDescriptor, String> properties = new HashMap<>();
     private final StateManager stateManager;
+    private final VariableRegistry variableRegistry;
 
     private final Map<String, List<Bulletin>> componentBulletinsCreated = new HashMap<>();
 
-    public MockReportingContext(final Map<String, ControllerService> controllerServices, final StateManager stateManager) {
+    public MockReportingContext(final Map<String, ControllerService> controllerServices, final StateManager stateManager, final VariableRegistry variableRegistry) {
         this.controllerServices = new HashMap<>();
         this.stateManager = stateManager;
+        this.variableRegistry = variableRegistry;
         for (final Map.Entry<String, ControllerService> entry : controllerServices.entrySet()) {
             this.controllerServices.put(entry.getKey(), new ControllerServiceConfiguration(entry.getValue()));
         }
@@ -58,7 +61,7 @@ public class MockReportingContext extends MockControllerServiceLookup implements
     @Override
     public PropertyValue getProperty(final PropertyDescriptor property) {
         final String configuredValue = properties.get(property);
-        return new MockPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, this);
+        return new MockPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, this, variableRegistry);
     }
 
     public void setProperty(final String propertyName, final String value) {

nifi-mock/src/main/java/org/apache/nifi/util/MockValidationContext.java

@@ -31,16 +31,20 @@ import org.apache.nifi.components.state.StateManager;
 import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.ControllerServiceLookup;
 import org.apache.nifi.expression.ExpressionLanguageCompiler;
+import org.apache.nifi.registry.VariableRegistry;
+
 
 public class MockValidationContext implements ValidationContext, ControllerServiceLookup {
 
     private final MockProcessContext context;
     private final Map<String, Boolean> expressionLanguageSupported;
     private final StateManager stateManager;
+    private final VariableRegistry variableRegistry;
 
-    public MockValidationContext(final MockProcessContext processContext, final StateManager stateManager) {
+    public MockValidationContext(final MockProcessContext processContext, final StateManager stateManager, final VariableRegistry variableRegistry) {
         this.context = processContext;
         this.stateManager = stateManager;
+        this.variableRegistry = variableRegistry;
 
         final Map<PropertyDescriptor, String> properties = processContext.getProperties();
         expressionLanguageSupported = new HashMap<>(properties.size());
@@ -56,18 +60,18 @@ public class MockValidationContext implements ValidationContext, ControllerServi
 
     @Override
     public PropertyValue newPropertyValue(final String rawValue) {
-        return new MockPropertyValue(rawValue, this);
+        return new MockPropertyValue(rawValue, this, variableRegistry);
     }
 
     @Override
     public ExpressionLanguageCompiler newExpressionLanguageCompiler() {
-        return new StandardExpressionLanguageCompiler();
+        return new StandardExpressionLanguageCompiler(variableRegistry);
     }
 
     @Override
     public ValidationContext getControllerServiceValidationContext(final ControllerService controllerService) {
-        final MockProcessContext serviceProcessContext = new MockProcessContext(controllerService, context, stateManager);
+        final MockProcessContext serviceProcessContext = new MockProcessContext(controllerService, context, stateManager, variableRegistry);
-        return new MockValidationContext(serviceProcessContext, stateManager);
+        return new MockValidationContext(serviceProcessContext, stateManager, variableRegistry);
     }
 
     @Override
@@ -141,4 +145,5 @@ public class MockValidationContext implements ValidationContext, ControllerServi
     public String getProcessGroupIdentifier() {
         return "unit test";
     }
+
 }

nifi-mock/src/main/java/org/apache/nifi/util/StandardProcessorTestRunner.java

@@ -65,6 +65,7 @@ import org.apache.nifi.processor.ProcessSessionFactory;
 import org.apache.nifi.processor.Processor;
 import org.apache.nifi.processor.Relationship;
 import org.apache.nifi.provenance.ProvenanceEventRecord;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.InitializationException;
 import org.apache.nifi.state.MockStateManager;
 import org.junit.Assert;
@@ -80,6 +81,7 @@ public class StandardProcessorTestRunner implements TestRunner {
     private final boolean triggerSerially;
     private final MockStateManager processorStateManager;
     private final Map<String, MockStateManager> controllerServiceStateManagers = new HashMap<>();
+    private final VariableRegistry variableRegistry;
 
     private int numThreads = 1;
     private final AtomicInteger invocations = new AtomicInteger(0);
@@ -87,14 +89,15 @@ public class StandardProcessorTestRunner implements TestRunner {
     private final Map<String, MockComponentLog> controllerServiceLoggers = new HashMap<>();
     private final MockComponentLog logger;
 
-    StandardProcessorTestRunner(final Processor processor) {
+    StandardProcessorTestRunner(final Processor processor,final VariableRegistry variableRegistry) {
         this.processor = processor;
         this.idGenerator = new AtomicLong(0L);
         this.sharedState = new SharedSessionState(processor, idGenerator);
         this.flowFileQueue = sharedState.getFlowFileQueue();
         this.sessionFactory = new MockSessionFactory(sharedState, processor);
         this.processorStateManager = new MockStateManager(processor);
-        this.context = new MockProcessContext(processor, processorStateManager);
+        this.variableRegistry = variableRegistry;
+        this.context = new MockProcessContext(processor, processorStateManager, variableRegistry);
 
         final MockProcessorInitializationContext mockInitContext = new MockProcessorInitializationContext(processor, context);
         processor.initialize(mockInitContext);
@@ -603,7 +606,7 @@ public class StandardProcessorTestRunner implements TestRunner {
             throw new IllegalStateException("Controller Service has not been added to this TestRunner via the #addControllerService method");
         }
 
-        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager).getControllerServiceValidationContext(service);
+        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager, variableRegistry).getControllerServiceValidationContext(service);
         final Collection<ValidationResult> results = context.getControllerService(service.getIdentifier()).validate(validationContext);
 
         for (final ValidationResult result : results) {
@@ -622,7 +625,7 @@ public class StandardProcessorTestRunner implements TestRunner {
             throw new IllegalStateException("Controller Service has not been added to this TestRunner via the #addControllerService method");
         }
 
-        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager).getControllerServiceValidationContext(service);
+        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager, variableRegistry).getControllerServiceValidationContext(service);
         final Collection<ValidationResult> results = context.getControllerService(service.getIdentifier()).validate(validationContext);
 
         for (final ValidationResult result : results) {
@@ -665,7 +668,7 @@ public class StandardProcessorTestRunner implements TestRunner {
         }
 
         try {
-            final ConfigurationContext configContext = new MockConfigurationContext(service, configuration.getProperties(), context);
+            final ConfigurationContext configContext = new MockConfigurationContext(service, configuration.getProperties(), context,variableRegistry);
             ReflectionUtils.invokeMethodsWithAnnotation(OnEnabled.class, service, configContext);
         } catch (final InvocationTargetException ite) {
             ite.getCause().printStackTrace();
@@ -737,7 +740,7 @@ public class StandardProcessorTestRunner implements TestRunner {
         final Map<PropertyDescriptor, String> curProps = configuration.getProperties();
         final Map<PropertyDescriptor, String> updatedProps = new HashMap<>(curProps);
 
-        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager).getControllerServiceValidationContext(service);
+        final ValidationContext validationContext = new MockValidationContext(context, serviceStateManager, variableRegistry).getControllerServiceValidationContext(service);
         final ValidationResult validationResult = property.validate(value, validationContext);
 
         updatedProps.put(property, value);

nifi-mock/src/main/java/org/apache/nifi/util/TestRunners.java

@@ -17,11 +17,17 @@
 package org.apache.nifi.util;
 
 import org.apache.nifi.processor.Processor;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 
 public class TestRunners {
 
     public static TestRunner newTestRunner(final Processor processor) {
-        return new StandardProcessorTestRunner(processor);
+        return newTestRunner(processor,VariableRegistryUtils.createSystemVariableRegistry());
+    }
+
+    public static TestRunner newTestRunner(final Processor processor, VariableRegistry variableRegistry){
+        return new StandardProcessorTestRunner(processor, variableRegistry);
     }
 
     public static TestRunner newTestRunner(final Class<? extends Processor> processorClass) {

nifi-mock/src/test/java/org/apache/nifi/util/CurrentTestStandardProcessorTestRunner.java

@@ -20,6 +20,7 @@ import org.apache.nifi.processor.AbstractProcessor;
 import org.apache.nifi.processor.ProcessContext;
 import org.apache.nifi.processor.ProcessSession;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.Assert;
 import org.junit.Test;
 
@@ -31,7 +32,7 @@ public class CurrentTestStandardProcessorTestRunner {
     @Test
     public void testOnScheduledCalledAfterRunFinished() {
         SlowRunProcessor processor = new SlowRunProcessor();
-        StandardProcessorTestRunner runner = new StandardProcessorTestRunner(processor);
+        StandardProcessorTestRunner runner = new StandardProcessorTestRunner(processor, VariableRegistryUtils.createSystemVariableRegistry());
         final int iterations = 5;
         runner.run(iterations);
         // if the counter is not equal to iterations, the the processor must have been unscheduled

nifi-mock/src/test/java/org/apache/nifi/util/TestMockProcessContext.java

@@ -32,6 +32,7 @@ import org.apache.nifi.processor.ProcessContext;
 import org.apache.nifi.processor.ProcessSession;
 import org.apache.nifi.processor.exception.ProcessException;
 import org.apache.nifi.processor.util.StandardValidators;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.Test;
 
 public class TestMockProcessContext {
@@ -39,7 +40,7 @@ public class TestMockProcessContext {
     @Test
     public void testRemoveProperty() {
         final DummyProcessor proc = new DummyProcessor();
-        final MockProcessContext context = new MockProcessContext(proc);
+        final MockProcessContext context = new MockProcessContext(proc, VariableRegistryUtils.createSystemVariableRegistry());
         context.setProperty(DummyProcessor.REQUIRED_PROP, "req-value");
         context.setProperty(DummyProcessor.OPTIONAL_PROP, "opt-value");
         context.setProperty(DummyProcessor.DEFAULTED_PROP, "custom-value");

nifi-nar-bundles/nifi-ambari-bundle/nifi-ambari-reporting-task/src/test/java/org/apache/nifi/reporting/ambari/TestAmbariReportingTask.java

@@ -20,6 +20,8 @@ import org.apache.nifi.controller.ConfigurationContext;
 import org.apache.nifi.controller.status.ProcessGroupStatus;
 import org.apache.nifi.controller.status.ProcessorStatus;
 import org.apache.nifi.logging.ComponentLog;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.reporting.EventAccess;
 import org.apache.nifi.reporting.InitializationException;
 import org.apache.nifi.reporting.ReportingContext;
@@ -43,6 +45,7 @@ import java.util.UUID;
 public class TestAmbariReportingTask {
 
     private ProcessGroupStatus status;
+    private VariableRegistry variableRegistry;
 
     @Before
     public void setup() {
@@ -73,6 +76,7 @@ public class TestAmbariReportingTask {
         Collection<ProcessGroupStatus> groupStatuses = new ArrayList<>();
         groupStatuses.add(groupStatus);
         status.setProcessGroupStatus(groupStatuses);
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     }
 
     @Test
@@ -105,11 +109,12 @@ public class TestAmbariReportingTask {
         // mock the ReportingContext for onTrigger(...)
         final ReportingContext context = Mockito.mock(ReportingContext.class);
         Mockito.when(context.getProperty(AmbariReportingTask.METRICS_COLLECTOR_URL))
-                .thenReturn(new MockPropertyValue(metricsUrl, null));
+                .thenReturn(new MockPropertyValue(metricsUrl, null, variableRegistry));
         Mockito.when(context.getProperty(AmbariReportingTask.APPLICATION_ID))
-                .thenReturn(new MockPropertyValue(applicationId, null));
+                .thenReturn(new MockPropertyValue(applicationId, null, variableRegistry));
         Mockito.when(context.getProperty(AmbariReportingTask.HOSTNAME))
-                .thenReturn(new MockPropertyValue(hostName, null));
+                .thenReturn(new MockPropertyValue(hostName, null, variableRegistry));
+
 
         final EventAccess eventAccess = Mockito.mock(EventAccess.class);
         Mockito.when(context.getEventAccess()).thenReturn(eventAccess);
@@ -121,7 +126,6 @@ public class TestAmbariReportingTask {
         task.setup(configurationContext);
         task.onTrigger(context);
     }
-
     // override the creation of the client to provide a mock
     private class TestableAmbariReportingTask extends AmbariReportingTask {
 

nifi-nar-bundles/nifi-elasticsearch-bundle/nifi-elasticsearch-processors/src/test/java/org/apache/nifi/processors/elasticsearch/TestFetchElasticsearch.java

@@ -18,6 +18,8 @@ package org.apache.nifi.processors.elasticsearch;
 
 import org.apache.nifi.processor.ProcessContext;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.ssl.SSLContextService;
 import org.apache.nifi.util.MockFlowFile;
 import org.apache.nifi.util.MockProcessContext;
@@ -62,11 +64,13 @@ public class TestFetchElasticsearch {
 
     private InputStream docExample;
     private TestRunner runner;
+    private VariableRegistry variableRegistry;
 
     @Before
     public void setUp() throws IOException {
         ClassLoader classloader = Thread.currentThread().getContextClassLoader();
         docExample = classloader.getResourceAsStream("DocumentExample.json");
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
 
     }
 
@@ -216,7 +220,7 @@ public class TestFetchElasticsearch {
             }
         };
 
-        MockProcessContext context = new MockProcessContext(processor);
+        MockProcessContext context = new MockProcessContext(processor, variableRegistry);
         processor.initialize(new MockProcessorInitializationContext(processor, context));
         processor.callCreateElasticsearchClient(context);
     }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-authorizer/src/main/java/org/apache/nifi/authorization/AuthorizerFactoryBean.java

@@ -25,6 +25,7 @@ import org.apache.nifi.authorization.generated.Authorizers;
 import org.apache.nifi.authorization.generated.Property;
 import org.apache.nifi.nar.ExtensionManager;
 import org.apache.nifi.nar.NarCloseable;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.NiFiProperties;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -72,8 +73,10 @@ public class AuthorizerFactoryBean implements FactoryBean, DisposableBean, Autho
 
     private Authorizer authorizer;
     private NiFiProperties properties;
+    private VariableRegistry variableRegistry;
     private final Map<String, Authorizer> authorizers = new HashMap<>();
 
+
     @Override
     public Authorizer getAuthorizer(String identifier) {
         return authorizers.get(identifier);
@@ -189,8 +192,7 @@ public class AuthorizerFactoryBean implements FactoryBean, DisposableBean, Autho
         for (final Property property : authorizer.getProperty()) {
             authorizerProperties.put(property.getName(), property.getValue());
         }
-
+        return new StandardAuthorizerConfigurationContext(authorizer.getIdentifier(), authorizerProperties, variableRegistry);
-        return new StandardAuthorizerConfigurationContext(authorizer.getIdentifier(), authorizerProperties);
     }
 
     private void performMethodInjection(final Authorizer instance, final Class authorizerClass) throws IllegalAccessException, IllegalArgumentException, InvocationTargetException {
@@ -484,4 +486,8 @@ public class AuthorizerFactoryBean implements FactoryBean, DisposableBean, Autho
     public void setProperties(NiFiProperties properties) {
         this.properties = properties;
     }
+
+    public void setVariableRegistry(VariableRegistry variableRegistry) {
+        this.variableRegistry = variableRegistry;
+    }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-authorizer/src/main/resources/nifi-authorizer-context.xml

@@ -21,6 +21,7 @@
     <!-- user/entity authorizer -->
     <bean id="authorizer" class="org.apache.nifi.authorization.AuthorizerFactoryBean">
         <property name="properties" ref="nifiProperties"/>
+        <property name="variableRegistry" ref="variableRegistry"/>
     </bean>
 
 </beans>

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-file-authorizer/src/test/java/org/apache/nifi/authorization/FileAuthorizerTest.java

@@ -21,6 +21,8 @@ import org.apache.nifi.authorization.AuthorizationResult.Result;
 import org.apache.nifi.authorization.exception.AuthorizerCreationException;
 import org.apache.nifi.authorization.resource.ResourceFactory;
 import org.apache.nifi.authorization.resource.ResourceType;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.NiFiProperties;
 import org.apache.nifi.util.file.FileUtils;
 import org.junit.After;
@@ -143,6 +145,7 @@ public class FileAuthorizerTest {
     private File flow;
     private File flowNoPorts;
     private File flowWithDns;
+    private VariableRegistry variableRegistry;
 
     private AuthorizerConfigurationContext configurationContext;
 
@@ -178,8 +181,8 @@ public class FileAuthorizerTest {
         when(properties.getFlowConfigurationFile()).thenReturn(flow);
 
         configurationContext = mock(AuthorizerConfigurationContext.class);
-        when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_AUTHORIZATIONS_FILE))).thenReturn(new StandardPropertyValue(primaryAuthorizations.getPath(), null));
+        when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_AUTHORIZATIONS_FILE))).thenReturn(new StandardPropertyValue(primaryAuthorizations.getPath(), null,variableRegistry));
-        when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_TENANTS_FILE))).thenReturn(new StandardPropertyValue(primaryTenants.getPath(), null));
+        when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_TENANTS_FILE))).thenReturn(new StandardPropertyValue(primaryTenants.getPath(), null,variableRegistry));
 
         authorizer = new FileAuthorizer();
         authorizer.setNiFiProperties(properties);
@@ -197,7 +200,7 @@ public class FileAuthorizerTest {
     @Test
     public void testOnConfiguredWhenLegacyUsersFileProvidedWithOverlappingRoles() throws Exception {
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users-multirole.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users-multirole.xml", null,VariableRegistryUtils.createSystemVariableRegistry()));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -222,7 +225,7 @@ public class FileAuthorizerTest {
         when(properties.getFlowConfigurationFile()).thenReturn(flowNoPorts);
 
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null,variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -242,7 +245,7 @@ public class FileAuthorizerTest {
     @Test
     public void testOnConfiguredWhenLegacyUsersFileProvided() throws Exception {
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null,VariableRegistryUtils.createSystemVariableRegistry()));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -392,7 +395,7 @@ public class FileAuthorizerTest {
         authorizer.setNiFiProperties(properties);
 
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users-with-dns.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users-with-dns.xml", null,variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -440,7 +443,7 @@ public class FileAuthorizerTest {
     @Test(expected = AuthorizerCreationException.class)
     public void testOnConfiguredWhenBadLegacyUsersFileProvided() throws Exception {
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/does-not-exist.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/does-not-exist.xml", null,VariableRegistryUtils.createSystemVariableRegistry()));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -450,12 +453,12 @@ public class FileAuthorizerTest {
     @Test(expected = AuthorizerCreationException.class)
     public void testOnConfiguredWhenInitialAdminAndLegacyUsersProvided() throws Exception {
         final String adminIdentity = "admin-user";
-
+        final VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null,variableRegistry));
 
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_LEGACY_AUTHORIZED_USERS_FILE)))
-                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null));
+                .thenReturn(new StandardPropertyValue("src/test/resources/authorized-users.xml", null,variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -480,7 +483,7 @@ public class FileAuthorizerTest {
         final String adminIdentity = "admin-user";
 
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null,VariableRegistryUtils.createSystemVariableRegistry()));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -510,6 +513,7 @@ public class FileAuthorizerTest {
 
     @Test
     public void testOnConfiguredWhenInitialAdminProvidedAndNoFlowExists() throws Exception {
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
         // setup NiFi properties to return a file that does not exist
         properties = mock(NiFiProperties.class);
         when(properties.getRestoreDirectory()).thenReturn(restoreAuthorizations.getParentFile());
@@ -518,7 +522,7 @@ public class FileAuthorizerTest {
 
         final String adminIdentity = "admin-user";
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null, variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -549,6 +553,7 @@ public class FileAuthorizerTest {
     @Test
     public void testOnConfiguredWhenInitialAdminProvidedAndFlowIsNull() throws Exception {
         // setup NiFi properties to return a file that does not exist
+        VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
         properties = mock(NiFiProperties.class);
         when(properties.getRestoreDirectory()).thenReturn(restoreAuthorizations.getParentFile());
         when(properties.getFlowConfigurationFile()).thenReturn(null);
@@ -556,7 +561,7 @@ public class FileAuthorizerTest {
 
         final String adminIdentity = "admin-user";
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null, variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -597,7 +602,7 @@ public class FileAuthorizerTest {
 
         final String adminIdentity = "CN=localhost, OU=Apache NiFi, O=Apache, L=Santa Monica, ST=CA, C=US";
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null,variableRegistry));
 
         writeFile(primaryAuthorizations, EMPTY_AUTHORIZATIONS_CONCISE);
         writeFile(primaryTenants, EMPTY_TENANTS_CONCISE);
@@ -615,7 +620,7 @@ public class FileAuthorizerTest {
         final String adminIdentity = "admin-user";
 
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null,VariableRegistryUtils.createSystemVariableRegistry()));
 
         final String nodeIdentity1 = "node1";
         final String nodeIdentity2 = "node2";
@@ -664,7 +669,7 @@ public class FileAuthorizerTest {
 
         final String adminIdentity = "CN=user1, OU=Apache NiFi, O=Apache, L=Santa Monica, ST=CA, C=US";
         when(configurationContext.getProperty(Mockito.eq(FileAuthorizer.PROP_INITIAL_ADMIN_IDENTITY)))
-                .thenReturn(new StandardPropertyValue(adminIdentity, null));
+                .thenReturn(new StandardPropertyValue(adminIdentity, null,variableRegistry));
 
         final String nodeIdentity1 = "CN=node1, OU=Apache NiFi, O=Apache, L=Santa Monica, ST=CA, C=US";
         final String nodeIdentity2 = "CN=node2, OU=Apache NiFi, O=Apache, L=Santa Monica, ST=CA, C=US";

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-authorization/src/main/java/org/apache/nifi/authorization/StandardAuthorizerConfigurationContext.java

@@ -18,6 +18,7 @@ package org.apache.nifi.authorization;
 
 import org.apache.nifi.attribute.expression.language.StandardPropertyValue;
 import org.apache.nifi.components.PropertyValue;
+import org.apache.nifi.registry.VariableRegistry;
 
 import java.util.Collections;
 import java.util.HashMap;
@@ -30,10 +31,12 @@ public class StandardAuthorizerConfigurationContext implements AuthorizerConfigu
 
     private final String identifier;
     private final Map<String, String> properties;
+    final VariableRegistry variableRegistry;
 
-    public StandardAuthorizerConfigurationContext(String identifier, Map<String, String> properties) {
+    public StandardAuthorizerConfigurationContext(String identifier, Map<String, String> properties, VariableRegistry variableRegistry) {
         this.identifier = identifier;
         this.properties = Collections.unmodifiableMap(new HashMap<String, String>(properties));
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -48,7 +51,7 @@ public class StandardAuthorizerConfigurationContext implements AuthorizerConfigu
 
     @Override
     public PropertyValue getProperty(String property) {
-        return new StandardPropertyValue(properties.get(property), null);
+        return new StandardPropertyValue(properties.get(property), null,variableRegistry);
     }
 
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/FlowController.java

@@ -158,6 +158,7 @@ import org.apache.nifi.provenance.ProvenanceEventRecord;
 import org.apache.nifi.provenance.ProvenanceEventType;
 import org.apache.nifi.provenance.ProvenanceRepository;
 import org.apache.nifi.provenance.StandardProvenanceEventRecord;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.remote.HttpRemoteSiteListener;
 import org.apache.nifi.remote.RemoteGroupPort;
 import org.apache.nifi.remote.RemoteResourceManager;
@@ -286,6 +287,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
     private final StateManagerProvider stateManagerProvider;
     private final long systemStartTime = System.currentTimeMillis(); // time at which the node was started
     private final ConcurrentMap<String, ReportingTaskNode> reportingTasks = new ConcurrentHashMap<>();
+    private final VariableRegistry variableRegistry;
     private final ConcurrentMap<String, ControllerServiceNode> rootControllerServices = new ConcurrentHashMap<>();
 
     private volatile ZooKeeperStateServer zooKeeperStateServer;
@@ -373,7 +375,8 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             final Authorizer authorizer,
             final AuditService auditService,
             final StringEncryptor encryptor,
-        final BulletinRepository bulletinRepo) {
+            final BulletinRepository bulletinRepo, VariableRegistry variableRegistry) {
+
         return new FlowController(
             flowFileEventRepo,
             properties,
@@ -384,7 +387,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             /* NodeProtocolSender */ null,
             bulletinRepo,
             /* cluster coordinator */ null,
-            /* heartbeat monitor */ null);
+            /* heartbeat monitor */ null, variableRegistry);
     }
 
     public static FlowController createClusteredInstance(
@@ -396,7 +399,9 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             final NodeProtocolSender protocolSender,
             final BulletinRepository bulletinRepo,
             final ClusterCoordinator clusterCoordinator,
-        final HeartbeatMonitor heartbeatMonitor) {
+            final HeartbeatMonitor heartbeatMonitor,
+            VariableRegistry variableRegistry) {
+
         final FlowController flowController = new FlowController(
             flowFileEventRepo,
             properties,
@@ -407,7 +412,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             protocolSender,
             bulletinRepo,
             clusterCoordinator,
-            heartbeatMonitor);
+            heartbeatMonitor, variableRegistry);
 
         return flowController;
     }
@@ -422,7 +427,8 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             final NodeProtocolSender protocolSender,
             final BulletinRepository bulletinRepo,
             final ClusterCoordinator clusterCoordinator,
-        final HeartbeatMonitor heartbeatMonitor) {
+            final HeartbeatMonitor heartbeatMonitor,
+            VariableRegistry variableRegistry) {
 
         maxTimerDrivenThreads = new AtomicInteger(10);
         maxEventDrivenThreads = new AtomicInteger(5);
@@ -443,6 +449,8 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
         counterRepositoryRef = new AtomicReference<CounterRepository>(new StandardCounterRepository());
 
         bulletinRepository = bulletinRepo;
+        this.variableRegistry = variableRegistry;
+
 
         try {
             this.provenanceRepository = createProvenanceRepository(properties);
@@ -458,20 +466,20 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
         }
 
         try {
-            this.stateManagerProvider = StandardStateManagerProvider.create(properties);
+            this.stateManagerProvider = StandardStateManagerProvider.create(properties, this.variableRegistry);
         } catch (final IOException e) {
             throw new RuntimeException(e);
         }
 
-        processScheduler = new StandardProcessScheduler(this, encryptor, stateManagerProvider);
+        processScheduler = new StandardProcessScheduler(this, encryptor, stateManagerProvider, this.variableRegistry);
         eventDrivenWorkerQueue = new EventDrivenWorkerQueue(false, false, processScheduler);
 
         final ProcessContextFactory contextFactory = new ProcessContextFactory(contentRepository, flowFileRepository, flowFileEventRepository, counterRepositoryRef.get(), provenanceRepository);
         processScheduler.setSchedulingAgent(SchedulingStrategy.EVENT_DRIVEN, new EventDrivenSchedulingAgent(
-            eventDrivenEngineRef.get(), this, stateManagerProvider, eventDrivenWorkerQueue, contextFactory, maxEventDrivenThreads.get(), encryptor));
+            eventDrivenEngineRef.get(), this, stateManagerProvider, eventDrivenWorkerQueue, contextFactory, maxEventDrivenThreads.get(), encryptor, this.variableRegistry));
 
-        final QuartzSchedulingAgent quartzSchedulingAgent = new QuartzSchedulingAgent(this, timerDrivenEngineRef.get(), contextFactory, encryptor);
+        final QuartzSchedulingAgent quartzSchedulingAgent = new QuartzSchedulingAgent(this, timerDrivenEngineRef.get(), contextFactory, encryptor, this.variableRegistry);
-        final TimerDrivenSchedulingAgent timerDrivenAgent = new TimerDrivenSchedulingAgent(this, timerDrivenEngineRef.get(), contextFactory, encryptor);
+        final TimerDrivenSchedulingAgent timerDrivenAgent = new TimerDrivenSchedulingAgent(this, timerDrivenEngineRef.get(), contextFactory, encryptor, this.variableRegistry);
         processScheduler.setSchedulingAgent(SchedulingStrategy.TIMER_DRIVEN, timerDrivenAgent);
         processScheduler.setSchedulingAgent(SchedulingStrategy.PRIMARY_NODE_ONLY, timerDrivenAgent);
         processScheduler.setSchedulingAgent(SchedulingStrategy.CRON_DRIVEN, quartzSchedulingAgent);
@@ -507,11 +515,11 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
 
         this.snippetManager = new SnippetManager();
 
-        rootGroup = new StandardProcessGroup(UUID.randomUUID().toString(), this, processScheduler, properties, encryptor, this);
+        rootGroup = new StandardProcessGroup(UUID.randomUUID().toString(), this, processScheduler, properties, encryptor, this, this.variableRegistry);
         rootGroup.setName(DEFAULT_ROOT_GROUP_NAME);
         instanceId = UUID.randomUUID().toString();
 
-        controllerServiceProvider = new StandardControllerServiceProvider(this, processScheduler, bulletinRepository, stateManagerProvider);
+        controllerServiceProvider = new StandardControllerServiceProvider(this, processScheduler, bulletinRepository, stateManagerProvider, this.variableRegistry);
 
         if (remoteInputSocketPort == null) {
             LOG.info("Not enabling RAW Socket Site-to-Site functionality because nifi.remote.input.socket.port is not set");
@@ -971,7 +979,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
      * @throws NullPointerException if the argument is null
      */
     public ProcessGroup createProcessGroup(final String id) {
-        return new StandardProcessGroup(requireNonNull(id).intern(), this, processScheduler, properties, encryptor, this);
+        return new StandardProcessGroup(requireNonNull(id).intern(), this, processScheduler, properties, encryptor, this, variableRegistry);
     }
 
     /**
@@ -1018,7 +1026,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             creationSuccessful = false;
         }
 
-        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(controllerServiceProvider);
+        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(controllerServiceProvider, variableRegistry);
         final ProcessorNode procNode;
         if (creationSuccessful) {
             procNode = new StandardProcessorNode(processor, id, validationContextFactory, processScheduler, controllerServiceProvider);
@@ -1295,7 +1303,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             // invoke any methods annotated with @OnShutdown on Controller Services
             for (final ControllerServiceNode serviceNode : getAllControllerServices()) {
                 try (final NarCloseable narCloseable = NarCloseable.withNarLoader()) {
-                    final ConfigurationContext configContext = new StandardConfigurationContext(serviceNode, controllerServiceProvider, null);
+                    final ConfigurationContext configContext = new StandardConfigurationContext(serviceNode, controllerServiceProvider, null, variableRegistry);
                     ReflectionUtils.quietlyInvokeMethodsWithAnnotation(OnShutdown.class, serviceNode.getControllerServiceImplementation(), configContext);
                 }
             }
@@ -2785,15 +2793,15 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
             }
         }
 
-        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(controllerServiceProvider);
+        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(controllerServiceProvider,variableRegistry);
         final ReportingTaskNode taskNode;
         if (creationSuccessful) {
-            taskNode = new StandardReportingTaskNode(task, id, this, processScheduler, validationContextFactory);
+            taskNode = new StandardReportingTaskNode(task, id, this, processScheduler, validationContextFactory, variableRegistry);
         } else {
             final String simpleClassName = type.contains(".") ? StringUtils.substringAfterLast(type, ".") : type;
             final String componentType = "(Missing) " + simpleClassName;
 
-            taskNode = new StandardReportingTaskNode(task, id, this, processScheduler, validationContextFactory, componentType, type);
+            taskNode = new StandardReportingTaskNode(task, id, this, processScheduler, validationContextFactory, componentType, type,variableRegistry);
         }
 
         taskNode.setName(task.getClass().getSimpleName());
@@ -3018,7 +3026,7 @@ public class FlowController implements EventAccess, ControllerServiceProvider, R
         service.verifyCanDelete();
 
         try (final NarCloseable x = NarCloseable.withNarLoader()) {
-            final ConfigurationContext configurationContext = new StandardConfigurationContext(service, controllerServiceProvider, null);
+            final ConfigurationContext configurationContext = new StandardConfigurationContext(service, controllerServiceProvider, null,variableRegistry);
             ReflectionUtils.quietlyInvokeMethodsWithAnnotation(OnRemoved.class, service.getControllerServiceImplementation(), configurationContext);
         }
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/reporting/AbstractReportingTaskNode.java

@@ -33,6 +33,7 @@ import org.apache.nifi.controller.ValidationContextFactory;
 import org.apache.nifi.controller.service.ControllerServiceNode;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
 import org.apache.nifi.controller.service.StandardConfigurationContext;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.ReportingTask;
 import org.apache.nifi.scheduling.SchedulingStrategy;
 import org.apache.nifi.util.FormatUtils;
@@ -49,24 +50,27 @@ public abstract class AbstractReportingTaskNode extends AbstractConfiguredCompon
     private volatile String comment;
     private volatile ScheduledState scheduledState = ScheduledState.STOPPED;
 
+    protected final VariableRegistry variableRegistry;
+
     public AbstractReportingTaskNode(final ReportingTask reportingTask, final String id,
         final ControllerServiceProvider controllerServiceProvider, final ProcessScheduler processScheduler,
-        final ValidationContextFactory validationContextFactory) {
+        final ValidationContextFactory validationContextFactory, final VariableRegistry variableRegistry) {
 
         this(reportingTask, id, controllerServiceProvider, processScheduler, validationContextFactory,
-            reportingTask.getClass().getSimpleName(), reportingTask.getClass().getCanonicalName());
+            reportingTask.getClass().getSimpleName(), reportingTask.getClass().getCanonicalName(),variableRegistry);
     }
 
 
     public AbstractReportingTaskNode(final ReportingTask reportingTask, final String id,
             final ControllerServiceProvider controllerServiceProvider, final ProcessScheduler processScheduler,
         final ValidationContextFactory validationContextFactory,
-        final String componentType, final String componentCanonicalClass) {
+        final String componentType, final String componentCanonicalClass, VariableRegistry variableRegistry) {
 
         super(reportingTask, id, validationContextFactory, controllerServiceProvider, componentType, componentCanonicalClass);
         this.reportingTask = reportingTask;
         this.processScheduler = processScheduler;
         this.serviceLookup = controllerServiceProvider;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -111,7 +115,7 @@ public abstract class AbstractReportingTaskNode extends AbstractConfiguredCompon
 
     @Override
     public ConfigurationContext getConfigurationContext() {
-        return new StandardConfigurationContext(this, serviceLookup, getSchedulingPeriod());
+        return new StandardConfigurationContext(this, serviceLookup, getSchedulingPeriod(), variableRegistry);
     }
 
     @Override
@@ -141,6 +145,7 @@ public abstract class AbstractReportingTaskNode extends AbstractConfiguredCompon
         return super.removeProperty(name);
     }
 
+
     public boolean isDisabled() {
         return scheduledState == ScheduledState.DISABLED;
     }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/reporting/StandardReportingContext.java

@@ -34,6 +34,7 @@ import org.apache.nifi.controller.FlowController;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
 import org.apache.nifi.events.BulletinFactory;
 import org.apache.nifi.groups.ProcessGroup;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.Bulletin;
 import org.apache.nifi.reporting.BulletinRepository;
 import org.apache.nifi.reporting.EventAccess;
@@ -50,16 +51,18 @@ public class StandardReportingContext implements ReportingContext, ControllerSer
     private final ControllerServiceProvider serviceProvider;
     private final Map<PropertyDescriptor, String> properties;
     private final Map<PropertyDescriptor, PreparedQuery> preparedQueries;
+    private final VariableRegistry variableRegistry;
 
     public StandardReportingContext(final FlowController flowController, final BulletinRepository bulletinRepository,
-            final Map<PropertyDescriptor, String> properties, final ControllerServiceProvider serviceProvider, final ReportingTask reportingTask) {
+                                    final Map<PropertyDescriptor, String> properties, final ControllerServiceProvider serviceProvider, final ReportingTask reportingTask,
+                                    final VariableRegistry variableRegistry) {
         this.flowController = flowController;
         this.eventAccess = flowController;
         this.bulletinRepository = bulletinRepository;
         this.properties = Collections.unmodifiableMap(properties);
         this.serviceProvider = serviceProvider;
         this.reportingTask = reportingTask;
-
+        this.variableRegistry = variableRegistry;
         preparedQueries = new HashMap<>();
         for (final Map.Entry<PropertyDescriptor, String> entry : properties.entrySet()) {
             final PropertyDescriptor desc = entry.getKey();
@@ -106,7 +109,7 @@ public class StandardReportingContext implements ReportingContext, ControllerSer
     @Override
     public PropertyValue getProperty(final PropertyDescriptor property) {
         final String configuredValue = properties.get(property);
-        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, this, preparedQueries.get(property));
+        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, this, preparedQueries.get(property), variableRegistry);
     }
 
     @Override
@@ -148,4 +151,5 @@ public class StandardReportingContext implements ReportingContext, ControllerSer
     public StateManager getStateManager() {
         return flowController.getStateManagerProvider().getStateManager(reportingTask.getIdentifier());
     }
+
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/reporting/StandardReportingTaskNode.java

@@ -24,6 +24,7 @@ import org.apache.nifi.controller.FlowController;
 import org.apache.nifi.controller.ProcessScheduler;
 import org.apache.nifi.controller.ReportingTaskNode;
 import org.apache.nifi.controller.ValidationContextFactory;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.ReportingContext;
 import org.apache.nifi.reporting.ReportingTask;
 
@@ -32,15 +33,16 @@ public class StandardReportingTaskNode extends AbstractReportingTaskNode impleme
     private final FlowController flowController;
 
     public StandardReportingTaskNode(final ReportingTask reportingTask, final String id, final FlowController controller,
-            final ProcessScheduler processScheduler, final ValidationContextFactory validationContextFactory) {
+                                     final ProcessScheduler processScheduler, final ValidationContextFactory validationContextFactory,
-        super(reportingTask, id, controller, processScheduler, validationContextFactory);
+                                     final VariableRegistry variableRegistry) {
+        super(reportingTask, id, controller, processScheduler, validationContextFactory, variableRegistry);
         this.flowController = controller;
     }
 
     public StandardReportingTaskNode(final ReportingTask reportingTask, final String id, final FlowController controller,
         final ProcessScheduler processScheduler, final ValidationContextFactory validationContextFactory,
-        final String componentType, final String canonicalClassName) {
+        final String componentType, final String canonicalClassName, VariableRegistry variableRegistry) {
-        super(reportingTask, id, controller, processScheduler, validationContextFactory, componentType, canonicalClassName);
+        super(reportingTask, id, controller, processScheduler, validationContextFactory, componentType, canonicalClassName,variableRegistry);
         this.flowController = controller;
     }
 
@@ -56,6 +58,6 @@ public class StandardReportingTaskNode extends AbstractReportingTaskNode impleme
 
     @Override
     public ReportingContext getReportingContext() {
-        return new StandardReportingContext(flowController, flowController.getBulletinRepository(), getProperties(), flowController, getReportingTask());
+        return new StandardReportingContext(flowController, flowController.getBulletinRepository(), getProperties(), flowController, getReportingTask(), variableRegistry);
     }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/scheduling/EventDrivenSchedulingAgent.java

@@ -45,6 +45,7 @@ import org.apache.nifi.processor.ProcessSessionFactory;
 import org.apache.nifi.processor.SimpleProcessLogger;
 import org.apache.nifi.processor.StandardProcessContext;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.Connectables;
 import org.apache.nifi.util.FormatUtils;
 import org.apache.nifi.util.ReflectionUtils;
@@ -61,6 +62,7 @@ public class EventDrivenSchedulingAgent extends AbstractSchedulingAgent {
     private final ProcessContextFactory contextFactory;
     private final AtomicInteger maxThreadCount;
     private final StringEncryptor encryptor;
+    private final VariableRegistry variableRegistry;
 
     private volatile String adminYieldDuration = "1 sec";
 
@@ -68,7 +70,8 @@ public class EventDrivenSchedulingAgent extends AbstractSchedulingAgent {
     private final ConcurrentMap<Connectable, ScheduleState> scheduleStates = new ConcurrentHashMap<>();
 
     public EventDrivenSchedulingAgent(final FlowEngine flowEngine, final ControllerServiceProvider serviceProvider, final StateManagerProvider stateManagerProvider,
-        final EventDrivenWorkerQueue workerQueue, final ProcessContextFactory contextFactory, final int maxThreadCount, final StringEncryptor encryptor) {
+                                      final EventDrivenWorkerQueue workerQueue, final ProcessContextFactory contextFactory, final int maxThreadCount, final StringEncryptor encryptor,
+                                      final VariableRegistry variableRegistry) {
         super(flowEngine);
         this.serviceProvider = serviceProvider;
         this.stateManagerProvider = stateManagerProvider;
@@ -76,6 +79,7 @@ public class EventDrivenSchedulingAgent extends AbstractSchedulingAgent {
         this.contextFactory = contextFactory;
         this.maxThreadCount = new AtomicInteger(maxThreadCount);
         this.encryptor = encryptor;
+        this.variableRegistry = variableRegistry;
 
         for (int i = 0; i < maxThreadCount; i++) {
             final Runnable eventDrivenTask = new EventDrivenTask(workerQueue);
@@ -185,7 +189,7 @@ public class EventDrivenSchedulingAgent extends AbstractSchedulingAgent {
                 if (connectable instanceof ProcessorNode) {
                     final ProcessorNode procNode = (ProcessorNode) connectable;
                     final StandardProcessContext standardProcessContext = new StandardProcessContext(procNode, serviceProvider,
-                        encryptor, getStateManager(connectable.getIdentifier()));
+                        encryptor, getStateManager(connectable.getIdentifier()), variableRegistry);
 
                     final long runNanos = procNode.getRunDuration(TimeUnit.NANOSECONDS);
                     final ProcessSessionFactory sessionFactory;

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/scheduling/QuartzSchedulingAgent.java

@@ -38,6 +38,7 @@ import org.apache.nifi.encrypt.StringEncryptor;
 import org.apache.nifi.engine.FlowEngine;
 import org.apache.nifi.processor.StandardProcessContext;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.FormatUtils;
 import org.quartz.CronExpression;
 import org.slf4j.Logger;
@@ -50,15 +51,18 @@ public class QuartzSchedulingAgent extends AbstractSchedulingAgent {
     private final FlowController flowController;
     private final ProcessContextFactory contextFactory;
     private final StringEncryptor encryptor;
+    private final VariableRegistry variableRegistry;
 
     private volatile String adminYieldDuration = "1 sec";
     private final Map<Object, List<AtomicBoolean>> canceledTriggers = new HashMap<>();
 
-    public QuartzSchedulingAgent(final FlowController flowController, final FlowEngine flowEngine, final ProcessContextFactory contextFactory, final StringEncryptor enryptor) {
+    public QuartzSchedulingAgent(final FlowController flowController, final FlowEngine flowEngine, final ProcessContextFactory contextFactory, final StringEncryptor enryptor,
+                                 final VariableRegistry variableRegistry) {
         super(flowEngine);
         this.flowController = flowController;
         this.contextFactory = contextFactory;
         this.encryptor = enryptor;
+        this.variableRegistry = variableRegistry;
     }
 
     private StateManager getStateManager(final String componentId) {
@@ -141,7 +145,7 @@ public class QuartzSchedulingAgent extends AbstractSchedulingAgent {
             if (connectable.getConnectableType() == ConnectableType.PROCESSOR) {
                 final ProcessorNode procNode = (ProcessorNode) connectable;
 
-                final StandardProcessContext standardProcContext = new StandardProcessContext(procNode, flowController, encryptor, getStateManager(connectable.getIdentifier()));
+                final StandardProcessContext standardProcContext = new StandardProcessContext(procNode, flowController, encryptor, getStateManager(connectable.getIdentifier()), variableRegistry);
                 ContinuallyRunProcessorTask runnableTask = new ContinuallyRunProcessorTask(this, procNode, flowController, contextFactory, scheduleState, standardProcContext);
                 continuallyRunTask = runnableTask;
             } else {

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/scheduling/StandardProcessScheduler.java

@@ -52,6 +52,7 @@ import org.apache.nifi.nar.NarCloseable;
 import org.apache.nifi.processor.Processor;
 import org.apache.nifi.processor.SimpleProcessLogger;
 import org.apache.nifi.processor.StandardProcessContext;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.ReportingTask;
 import org.apache.nifi.scheduling.SchedulingStrategy;
 import org.apache.nifi.util.FormatUtils;
@@ -81,12 +82,14 @@ public final class StandardProcessScheduler implements ProcessScheduler {
     private final ScheduledExecutorService componentMonitoringThreadPool = new FlowEngine(8, "StandardProcessScheduler", true);
 
     private final StringEncryptor encryptor;
+    private final VariableRegistry variableRegistry;
 
     public StandardProcessScheduler(final ControllerServiceProvider controllerServiceProvider, final StringEncryptor encryptor,
-        final StateManagerProvider stateManagerProvider) {
+                                    final StateManagerProvider stateManagerProvider, final VariableRegistry variableRegistry) {
         this.controllerServiceProvider = controllerServiceProvider;
         this.encryptor = encryptor;
         this.stateManagerProvider = stateManagerProvider;
+        this.variableRegistry = variableRegistry;
 
         administrativeYieldDuration = NiFiProperties.getInstance().getAdministrativeYieldDuration();
         administrativeYieldMillis = FormatUtils.getTimeDuration(administrativeYieldDuration, TimeUnit.MILLISECONDS);
@@ -290,7 +293,7 @@ public final class StandardProcessScheduler implements ProcessScheduler {
     @Override
     public synchronized void startProcessor(final ProcessorNode procNode) {
         StandardProcessContext processContext = new StandardProcessContext(procNode, this.controllerServiceProvider,
-                this.encryptor, getStateManager(procNode.getIdentifier()));
+                this.encryptor, getStateManager(procNode.getIdentifier()), variableRegistry);
         final ScheduleState scheduleState = getScheduleState(requireNonNull(procNode));
 
         SchedulingAgentCallback callback = new SchedulingAgentCallback() {
@@ -324,7 +327,7 @@ public final class StandardProcessScheduler implements ProcessScheduler {
     @Override
     public synchronized void stopProcessor(final ProcessorNode procNode) {
         StandardProcessContext processContext = new StandardProcessContext(procNode, this.controllerServiceProvider,
-                this.encryptor, getStateManager(procNode.getIdentifier()));
+                this.encryptor, getStateManager(procNode.getIdentifier()), variableRegistry);
         final ScheduleState state = getScheduleState(procNode);
 
         procNode.stop(this.componentLifeCycleThreadPool, processContext, new Callable<Boolean>() {

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/scheduling/TimerDrivenSchedulingAgent.java

@@ -37,6 +37,7 @@ import org.apache.nifi.engine.FlowEngine;
 import org.apache.nifi.processor.ProcessContext;
 import org.apache.nifi.processor.StandardProcessContext;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.FormatUtils;
 import org.apache.nifi.util.NiFiProperties;
 import org.slf4j.Logger;
@@ -50,14 +51,17 @@ public class TimerDrivenSchedulingAgent extends AbstractSchedulingAgent {
     private final FlowController flowController;
     private final ProcessContextFactory contextFactory;
     private final StringEncryptor encryptor;
+    private final VariableRegistry variableRegistry;
 
     private volatile String adminYieldDuration = "1 sec";
 
-    public TimerDrivenSchedulingAgent(final FlowController flowController, final FlowEngine flowEngine, final ProcessContextFactory contextFactory, final StringEncryptor encryptor) {
+    public TimerDrivenSchedulingAgent(final FlowController flowController, final FlowEngine flowEngine, final ProcessContextFactory contextFactory, final StringEncryptor encryptor,
+                                      final VariableRegistry variableRegistry) {
         super(flowEngine);
         this.flowController = flowController;
         this.contextFactory = contextFactory;
         this.encryptor = encryptor;
+        this.variableRegistry = variableRegistry;
 
         final String boredYieldDuration = NiFiProperties.getInstance().getBoredYieldDuration();
         try {
@@ -100,7 +104,7 @@ public class TimerDrivenSchedulingAgent extends AbstractSchedulingAgent {
             // Determine the task to run and create it.
             if (connectable.getConnectableType() == ConnectableType.PROCESSOR) {
                 final ProcessorNode procNode = (ProcessorNode) connectable;
-                final StandardProcessContext standardProcContext = new StandardProcessContext(procNode, flowController, encryptor, getStateManager(connectable.getIdentifier()));
+                final StandardProcessContext standardProcContext = new StandardProcessContext(procNode, flowController, encryptor, getStateManager(connectable.getIdentifier()), variableRegistry);
                 final ContinuallyRunProcessorTask runnableTask = new ContinuallyRunProcessorTask(this, procNode, flowController,
                         contextFactory, scheduleState, standardProcContext);
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/service/StandardConfigurationContext.java

@@ -28,6 +28,7 @@ import org.apache.nifi.components.PropertyValue;
 import org.apache.nifi.controller.ConfigurationContext;
 import org.apache.nifi.controller.ConfiguredComponent;
 import org.apache.nifi.controller.ControllerServiceLookup;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.FormatUtils;
 
 public class StandardConfigurationContext implements ConfigurationContext {
@@ -35,13 +36,17 @@ public class StandardConfigurationContext implements ConfigurationContext {
     private final ConfiguredComponent component;
     private final ControllerServiceLookup serviceLookup;
     private final Map<PropertyDescriptor, PreparedQuery> preparedQueries;
+    private final VariableRegistry variableRegistry;
     private final String schedulingPeriod;
     private final Long schedulingNanos;
 
-    public StandardConfigurationContext(final ConfiguredComponent component, final ControllerServiceLookup serviceLookup, final String schedulingPeriod) {
+    public StandardConfigurationContext(final ConfiguredComponent component, final ControllerServiceLookup serviceLookup, final String schedulingPeriod,
+                                        final VariableRegistry variableRegistry) {
         this.component = component;
         this.serviceLookup = serviceLookup;
         this.schedulingPeriod = schedulingPeriod;
+        this.variableRegistry = variableRegistry;
+
         if (schedulingPeriod == null) {
             schedulingNanos = null;
         } else {
@@ -68,7 +73,7 @@ public class StandardConfigurationContext implements ConfigurationContext {
     @Override
     public PropertyValue getProperty(final PropertyDescriptor property) {
         final String configuredValue = component.getProperty(property);
-        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, serviceLookup, preparedQueries.get(property));
+        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, serviceLookup, preparedQueries.get(property), variableRegistry);
     }
 
     @Override

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/service/StandardControllerServiceNode.java

@@ -48,6 +48,7 @@ import org.apache.nifi.controller.ValidationContextFactory;
 import org.apache.nifi.groups.ProcessGroup;
 import org.apache.nifi.logging.ComponentLog;
 import org.apache.nifi.processor.SimpleProcessLogger;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.ReflectionUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -59,7 +60,7 @@ public class StandardControllerServiceNode extends AbstractConfiguredComponent i
     private final ControllerService proxedControllerService;
     private final ControllerService implementation;
     private final ControllerServiceProvider serviceProvider;
-
+    private final VariableRegistry variableRegistry;
     private final AtomicReference<ControllerServiceState> stateRef = new AtomicReference<>(ControllerServiceState.DISABLED);
 
     private final ReadWriteLock rwLock = new ReentrantReadWriteLock();
@@ -73,21 +74,24 @@ public class StandardControllerServiceNode extends AbstractConfiguredComponent i
     private final AtomicBoolean active;
 
     public StandardControllerServiceNode(final ControllerService proxiedControllerService, final ControllerService implementation, final String id,
-        final ValidationContextFactory validationContextFactory, final ControllerServiceProvider serviceProvider) {
+                                         final ValidationContextFactory validationContextFactory, final ControllerServiceProvider serviceProvider,
+                                         final VariableRegistry variableRegistry) {
 
         this(proxiedControllerService, implementation, id, validationContextFactory, serviceProvider,
-            implementation.getClass().getSimpleName(), implementation.getClass().getCanonicalName());
+            implementation.getClass().getSimpleName(), implementation.getClass().getCanonicalName(), variableRegistry);
     }
 
     public StandardControllerServiceNode(final ControllerService proxiedControllerService, final ControllerService implementation, final String id,
                                          final ValidationContextFactory validationContextFactory, final ControllerServiceProvider serviceProvider,
-        final String componentType, final String componentCanonicalClass) {
+                                         final String componentType, final String componentCanonicalClass, VariableRegistry variableRegistry) {
 
         super(implementation, id, validationContextFactory, serviceProvider, componentType, componentCanonicalClass);
         this.proxedControllerService = proxiedControllerService;
         this.implementation = implementation;
         this.serviceProvider = serviceProvider;
         this.active = new AtomicBoolean();
+        this.variableRegistry = variableRegistry;
+
     }
 
     @Override
@@ -335,7 +339,7 @@ public class StandardControllerServiceNode extends AbstractConfiguredComponent i
     public void enable(final ScheduledExecutorService scheduler, final long administrativeYieldMillis) {
         if (this.stateRef.compareAndSet(ControllerServiceState.DISABLED, ControllerServiceState.ENABLING)) {
             this.active.set(true);
-            final ConfigurationContext configContext = new StandardConfigurationContext(this, this.serviceProvider, null);
+            final ConfigurationContext configContext = new StandardConfigurationContext(this, this.serviceProvider, null, variableRegistry);
             scheduler.execute(new Runnable() {
                 @Override
                 public void run() {
@@ -398,7 +402,7 @@ public class StandardControllerServiceNode extends AbstractConfiguredComponent i
         }
 
         if (this.stateRef.compareAndSet(ControllerServiceState.ENABLED, ControllerServiceState.DISABLING)) {
-            final ConfigurationContext configContext = new StandardConfigurationContext(this, this.serviceProvider, null);
+            final ConfigurationContext configContext = new StandardConfigurationContext(this, this.serviceProvider, null, variableRegistry);
             scheduler.execute(new Runnable() {
                 @Override
                 public void run() {

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/service/StandardControllerServiceProvider.java

@@ -55,6 +55,8 @@ import org.apache.nifi.nar.ExtensionManager;
 import org.apache.nifi.nar.NarCloseable;
 import org.apache.nifi.processor.SimpleProcessLogger;
 import org.apache.nifi.processor.StandardValidationContextFactory;
+import org.apache.nifi.registry.VariableRegistry;
+
 import org.apache.nifi.reporting.BulletinRepository;
 import org.apache.nifi.reporting.Severity;
 import org.apache.nifi.util.ReflectionUtils;
@@ -69,6 +71,7 @@ public class StandardControllerServiceProvider implements ControllerServiceProvi
     private static final Set<Method> validDisabledMethods;
     private final BulletinRepository bulletinRepo;
     private final StateManagerProvider stateManagerProvider;
+    private final VariableRegistry variableRegistry;
     private final FlowController flowController;
 
     static {
@@ -84,12 +87,13 @@ public class StandardControllerServiceProvider implements ControllerServiceProvi
     }
 
     public StandardControllerServiceProvider(final FlowController flowController, final ProcessScheduler scheduler, final BulletinRepository bulletinRepo,
-        final StateManagerProvider stateManagerProvider) {
+        final StateManagerProvider stateManagerProvider,final VariableRegistry variableRegistry) {
 
         this.flowController = flowController;
         this.processScheduler = scheduler;
         this.bulletinRepo = bulletinRepo;
         this.stateManagerProvider = stateManagerProvider;
+        this.variableRegistry = variableRegistry;
     }
 
 
@@ -187,9 +191,9 @@ public class StandardControllerServiceProvider implements ControllerServiceProvi
             final ComponentLog serviceLogger = new SimpleProcessLogger(id, originalService);
             originalService.initialize(new StandardControllerServiceInitializationContext(id, serviceLogger, this, getStateManager(id)));
 
-            final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(this);
+            final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(this, variableRegistry);
 
-            final ControllerServiceNode serviceNode = new StandardControllerServiceNode(proxiedService, originalService, id, validationContextFactory, this);
+            final ControllerServiceNode serviceNode = new StandardControllerServiceNode(proxiedService, originalService, id, validationContextFactory, this, variableRegistry);
             serviceNodeHolder.set(serviceNode);
             serviceNode.setName(rawClass.getSimpleName());
 
@@ -258,7 +262,7 @@ public class StandardControllerServiceProvider implements ControllerServiceProvi
         final String componentType = "(Missing) " + simpleClassName;
 
         final ControllerServiceNode serviceNode = new StandardControllerServiceNode(proxiedService, proxiedService, id,
-            new StandardValidationContextFactory(this), this, componentType, type);
+            new StandardValidationContextFactory(this,variableRegistry), this, componentType, type, variableRegistry);
         return serviceNode;
     }
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/controller/state/manager/StandardStateManagerProvider.java

@@ -46,6 +46,7 @@ import org.apache.nifi.controller.state.config.StateProviderConfiguration;
 import org.apache.nifi.framework.security.util.SslContextFactory;
 import org.apache.nifi.nar.ExtensionManager;
 import org.apache.nifi.processor.StandardValidationContext;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.NiFiProperties;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -62,12 +63,12 @@ public class StandardStateManagerProvider implements StateManagerProvider {
         this.clusterStateProvider = clusterStateProvider;
     }
 
-    public static StateManagerProvider create(final NiFiProperties properties) throws ConfigParseException, IOException {
+    public static StateManagerProvider create(final NiFiProperties properties, final VariableRegistry variableRegistry) throws ConfigParseException, IOException {
-        final StateProvider localProvider = createLocalStateProvider(properties);
+        final StateProvider localProvider = createLocalStateProvider(properties,variableRegistry);
 
         final StateProvider clusterProvider;
         if (properties.isNode()) {
-            clusterProvider = createClusteredStateProvider(properties);
+            clusterProvider = createClusteredStateProvider(properties,variableRegistry);
         } else {
             clusterProvider = null;
         }
@@ -75,19 +76,20 @@ public class StandardStateManagerProvider implements StateManagerProvider {
         return new StandardStateManagerProvider(localProvider, clusterProvider);
     }
 
-    private static StateProvider createLocalStateProvider(final NiFiProperties properties) throws IOException, ConfigParseException {
+    private static StateProvider createLocalStateProvider(final NiFiProperties properties, final VariableRegistry variableRegistry) throws IOException, ConfigParseException {
         final File configFile = properties.getStateManagementConfigFile();
-        return createStateProvider(configFile, Scope.LOCAL, properties);
+        return createStateProvider(configFile, Scope.LOCAL, properties, variableRegistry);
     }
 
 
-    private static StateProvider createClusteredStateProvider(final NiFiProperties properties) throws IOException, ConfigParseException {
+    private static StateProvider createClusteredStateProvider(final NiFiProperties properties, final VariableRegistry variableRegistry) throws IOException, ConfigParseException {
         final File configFile = properties.getStateManagementConfigFile();
-        return createStateProvider(configFile, Scope.CLUSTER, properties);
+        return createStateProvider(configFile, Scope.CLUSTER, properties, variableRegistry);
     }
 
 
-    private static StateProvider createStateProvider(final File configFile, final Scope scope, final NiFiProperties properties) throws ConfigParseException, IOException {
+    private static StateProvider createStateProvider(final File configFile, final Scope scope, final NiFiProperties properties,
+                                                     final VariableRegistry variableRegistry) throws ConfigParseException, IOException {
         final String providerId;
         final String providerIdPropertyName;
         final String providerDescription;
@@ -166,17 +168,18 @@ public class StandardStateManagerProvider implements StateManagerProvider {
                 + " is configured to use scope " + scope);
         }
 
+        //create variable registry
         final Map<PropertyDescriptor, PropertyValue> propertyMap = new HashMap<>();
         final Map<PropertyDescriptor, String> propertyStringMap = new HashMap<>();
         for (final PropertyDescriptor descriptor : provider.getPropertyDescriptors()) {
-            propertyMap.put(descriptor, new StandardPropertyValue(descriptor.getDefaultValue(), null));
+            propertyMap.put(descriptor, new StandardPropertyValue(descriptor.getDefaultValue(),null, variableRegistry));
             propertyStringMap.put(descriptor, descriptor.getDefaultValue());
         }
 
         for (final Map.Entry<String, String> entry : providerConfig.getProperties().entrySet()) {
             final PropertyDescriptor descriptor = provider.getPropertyDescriptor(entry.getKey());
             propertyStringMap.put(descriptor, entry.getValue());
-            propertyMap.put(descriptor, new StandardPropertyValue(entry.getValue(), null));
+            propertyMap.put(descriptor, new StandardPropertyValue(entry.getValue(),null, variableRegistry));
         }
 
         final SSLContext sslContext = SslContextFactory.createSslContext(properties, false);
@@ -186,7 +189,7 @@ public class StandardStateManagerProvider implements StateManagerProvider {
             provider.initialize(initContext);
         }
 
-        final ValidationContext validationContext = new StandardValidationContext(null, propertyStringMap, null, null, null);
+        final ValidationContext validationContext = new StandardValidationContext(null, propertyStringMap, null, null, null,variableRegistry);
         final Collection<ValidationResult> results = provider.validate(validationContext);
         final StringBuilder validationFailures = new StringBuilder();
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/groups/StandardProcessGroup.java

@@ -54,6 +54,7 @@ import org.apache.nifi.encrypt.StringEncryptor;
 import org.apache.nifi.logging.LogRepositoryFactory;
 import org.apache.nifi.nar.NarCloseable;
 import org.apache.nifi.processor.StandardProcessContext;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.remote.RemoteGroupPort;
 import org.apache.nifi.remote.RootGroupPort;
 import org.apache.nifi.util.NiFiProperties;
@@ -101,6 +102,7 @@ public final class StandardProcessGroup implements ProcessGroup {
     private final Map<String, ControllerServiceNode> controllerServices = new HashMap<>();
     private final Map<String, Template> templates = new HashMap<>();
     private final StringEncryptor encryptor;
+    private final VariableRegistry variableRegistry;
 
     private final ReentrantReadWriteLock rwLock = new ReentrantReadWriteLock();
     private final Lock readLock = rwLock.readLock();
@@ -109,7 +111,8 @@ public final class StandardProcessGroup implements ProcessGroup {
     private static final Logger LOG = LoggerFactory.getLogger(StandardProcessGroup.class);
 
     public StandardProcessGroup(final String id, final ControllerServiceProvider serviceProvider, final StandardProcessScheduler scheduler,
-        final NiFiProperties nifiProps, final StringEncryptor encryptor, final FlowController flowController) {
+         final NiFiProperties nifiProps, final StringEncryptor encryptor, final FlowController flowController,
+        final VariableRegistry variableRegistry) {
         this.id = id;
         this.controllerServiceProvider = serviceProvider;
         this.parent = new AtomicReference<>();
@@ -117,6 +120,7 @@ public final class StandardProcessGroup implements ProcessGroup {
         this.comments = new AtomicReference<>("");
         this.encryptor = encryptor;
         this.flowController = flowController;
+        this.variableRegistry = variableRegistry;
 
         name = new AtomicReference<>();
         position = new AtomicReference<>(new Position(0D, 0D));
@@ -345,7 +349,7 @@ public final class StandardProcessGroup implements ProcessGroup {
     private void shutdown(final ProcessGroup procGroup) {
         for (final ProcessorNode node : procGroup.getProcessors()) {
             try (final NarCloseable x = NarCloseable.withNarLoader()) {
-                final StandardProcessContext processContext = new StandardProcessContext(node, controllerServiceProvider, encryptor, getStateManager(node.getIdentifier()));
+                final StandardProcessContext processContext = new StandardProcessContext(node, controllerServiceProvider, encryptor, getStateManager(node.getIdentifier()),variableRegistry);
                 ReflectionUtils.quietlyInvokeMethodsWithAnnotation(OnShutdown.class, node.getProcessor(), processContext);
             }
         }
@@ -710,7 +714,7 @@ public final class StandardProcessGroup implements ProcessGroup {
             }
 
             try (final NarCloseable x = NarCloseable.withNarLoader()) {
-                final StandardProcessContext processContext = new StandardProcessContext(processor, controllerServiceProvider, encryptor, getStateManager(processor.getIdentifier()));
+                final StandardProcessContext processContext = new StandardProcessContext(processor, controllerServiceProvider, encryptor, getStateManager(processor.getIdentifier()),variableRegistry);
                 ReflectionUtils.quietlyInvokeMethodsWithAnnotation(OnRemoved.class, processor.getProcessor(), processContext);
             } catch (final Exception e) {
                 throw new ComponentLifeCycleException("Failed to invoke 'OnRemoved' methods of " + processor, e);
@@ -1839,7 +1843,7 @@ public final class StandardProcessGroup implements ProcessGroup {
             service.verifyCanDelete();
 
             try (final NarCloseable x = NarCloseable.withNarLoader()) {
-                final ConfigurationContext configurationContext = new StandardConfigurationContext(service, controllerServiceProvider, null);
+                final ConfigurationContext configurationContext = new StandardConfigurationContext(service, controllerServiceProvider, null, variableRegistry);
                 ReflectionUtils.quietlyInvokeMethodsWithAnnotation(OnRemoved.class, service.getControllerServiceImplementation(), configurationContext);
             }
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/processor/StandardProcessContext.java

@@ -36,6 +36,7 @@ import org.apache.nifi.controller.ControllerServiceLookup;
 import org.apache.nifi.controller.ProcessorNode;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
 import org.apache.nifi.encrypt.StringEncryptor;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.util.Connectables;
 
 public class StandardProcessContext implements ProcessContext, ControllerServiceLookup {
@@ -45,12 +46,15 @@ public class StandardProcessContext implements ProcessContext, ControllerService
     private final Map<PropertyDescriptor, PreparedQuery> preparedQueries;
     private final StringEncryptor encryptor;
     private final StateManager stateManager;
+    private final VariableRegistry variableRegistry;
 
-    public StandardProcessContext(final ProcessorNode processorNode, final ControllerServiceProvider controllerServiceProvider, final StringEncryptor encryptor, final StateManager stateManager) {
+    public StandardProcessContext(final ProcessorNode processorNode, final ControllerServiceProvider controllerServiceProvider, final StringEncryptor encryptor, final StateManager stateManager,
+                                  final VariableRegistry variableRegistry) {
         this.procNode = processorNode;
         this.controllerServiceProvider = controllerServiceProvider;
         this.encryptor = encryptor;
         this.stateManager = stateManager;
+        this.variableRegistry = variableRegistry;
 
         preparedQueries = new HashMap<>();
         for (final Map.Entry<PropertyDescriptor, String> entry : procNode.getProperties().entrySet()) {
@@ -86,12 +90,12 @@ public class StandardProcessContext implements ProcessContext, ControllerService
         final String setPropertyValue = procNode.getProperty(descriptor);
         final String propValue = (setPropertyValue == null) ? descriptor.getDefaultValue() : setPropertyValue;
 
-        return new StandardPropertyValue(propValue, this, preparedQueries.get(descriptor));
+        return new StandardPropertyValue(propValue, this, preparedQueries.get(descriptor), variableRegistry);
     }
 
     @Override
     public PropertyValue newPropertyValue(final String rawValue) {
-        return new StandardPropertyValue(rawValue, this, Query.prepare(rawValue));
+        return new StandardPropertyValue(rawValue, this, Query.prepare(rawValue), variableRegistry);
     }
 
     @Override
@@ -221,4 +225,5 @@ public class StandardProcessContext implements ProcessContext, ControllerService
     public String getName() {
         return procNode.getName();
     }
+
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/processor/StandardValidationContext.java

@@ -1,3 +1,4 @@
+
 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
@@ -36,6 +37,7 @@ import org.apache.nifi.controller.service.ControllerServiceNode;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
 import org.apache.nifi.expression.ExpressionLanguageCompiler;
 import org.apache.nifi.groups.ProcessGroup;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class StandardValidationContext implements ValidationContext {
 
@@ -45,12 +47,13 @@ public class StandardValidationContext implements ValidationContext {
     private final Map<String, Boolean> expressionLanguageSupported;
     private final String annotationData;
     private final Set<String> serviceIdentifiersToNotValidate;
+    private final VariableRegistry variableRegistry;
     private final String groupId;
     private final String componentId;
 
     public StandardValidationContext(final ControllerServiceProvider controllerServiceProvider, final Map<PropertyDescriptor, String> properties,
-            final String annotationData, final String groupId, final String componentId) {
+            final String annotationData, final String groupId, final String componentId, VariableRegistry variableRegistry) {
-        this(controllerServiceProvider, Collections.<String> emptySet(), properties, annotationData, groupId, componentId);
+        this(controllerServiceProvider, Collections.<String> emptySet(), properties, annotationData, groupId, componentId,variableRegistry);
     }
 
     public StandardValidationContext(
@@ -59,11 +62,12 @@ public class StandardValidationContext implements ValidationContext {
             final Map<PropertyDescriptor, String> properties,
             final String annotationData,
             final String groupId,
-            final String componentId) {
+            final String componentId, VariableRegistry variableRegistry) {
         this.controllerServiceProvider = controllerServiceProvider;
         this.properties = new HashMap<>(properties);
         this.annotationData = annotationData;
         this.serviceIdentifiersToNotValidate = serviceIdentifiersToNotValidate;
+        this.variableRegistry = variableRegistry;
         this.groupId = groupId;
         this.componentId = componentId;
 
@@ -87,12 +91,12 @@ public class StandardValidationContext implements ValidationContext {
 
     @Override
     public PropertyValue newPropertyValue(final String rawValue) {
-        return new StandardPropertyValue(rawValue, controllerServiceProvider, Query.prepare(rawValue));
+        return new StandardPropertyValue(rawValue, controllerServiceProvider, Query.prepare(rawValue), variableRegistry);
     }
 
     @Override
     public ExpressionLanguageCompiler newExpressionLanguageCompiler() {
-        return new StandardExpressionLanguageCompiler();
+        return new StandardExpressionLanguageCompiler(variableRegistry);
     }
 
     @Override
@@ -100,13 +104,13 @@ public class StandardValidationContext implements ValidationContext {
         final ControllerServiceNode serviceNode = controllerServiceProvider.getControllerServiceNode(controllerService.getIdentifier());
         final ProcessGroup serviceGroup = serviceNode.getProcessGroup();
         final String serviceGroupId = serviceGroup == null ? null : serviceGroup.getIdentifier();
-        return new StandardValidationContext(controllerServiceProvider, serviceNode.getProperties(), serviceNode.getAnnotationData(), serviceGroupId, serviceNode.getIdentifier());
+        return new StandardValidationContext(controllerServiceProvider, serviceNode.getProperties(), serviceNode.getAnnotationData(), serviceGroupId, serviceNode.getIdentifier(),variableRegistry);
     }
 
     @Override
     public PropertyValue getProperty(final PropertyDescriptor property) {
         final String configuredValue = properties.get(property);
-        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, controllerServiceProvider, preparedQueries.get(property));
+        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, controllerServiceProvider, preparedQueries.get(property), variableRegistry);
     }
 
     @Override

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/processor/StandardValidationContextFactory.java

@@ -23,23 +23,26 @@ import org.apache.nifi.components.PropertyDescriptor;
 import org.apache.nifi.components.ValidationContext;
 import org.apache.nifi.controller.ValidationContextFactory;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
+import org.apache.nifi.registry.VariableRegistry;
 
 public class StandardValidationContextFactory implements ValidationContextFactory {
 
     private final ControllerServiceProvider serviceProvider;
+    private final VariableRegistry variableRegistry;
 
-    public StandardValidationContextFactory(final ControllerServiceProvider serviceProvider) {
+    public StandardValidationContextFactory(final ControllerServiceProvider serviceProvider, final VariableRegistry variableRegistry) {
         this.serviceProvider = serviceProvider;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
     public ValidationContext newValidationContext(final Map<PropertyDescriptor, String> properties, final String annotationData, final String groupId, final String componentId) {
-        return new StandardValidationContext(serviceProvider, properties, annotationData, groupId, componentId);
+        return new StandardValidationContext(serviceProvider, properties, annotationData, groupId, componentId,variableRegistry);
     }
 
     @Override
     public ValidationContext newValidationContext(final Set<String> serviceIdentifiersToNotValidate,
             final Map<PropertyDescriptor, String> properties, final String annotationData, final String groupId, String componentId) {
-        return new StandardValidationContext(serviceProvider, serviceIdentifiersToNotValidate, properties, annotationData, groupId, componentId);
+        return new StandardValidationContext(serviceProvider, serviceIdentifiersToNotValidate, properties, annotationData, groupId, componentId,variableRegistry);
     }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/java/org/apache/nifi/spring/FlowControllerFactoryBean.java

@@ -24,8 +24,11 @@ import org.apache.nifi.cluster.protocol.NodeProtocolSender;
 import org.apache.nifi.controller.FlowController;
 import org.apache.nifi.controller.repository.FlowFileEventRepository;
 import org.apache.nifi.encrypt.StringEncryptor;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.reporting.BulletinRepository;
 import org.apache.nifi.util.NiFiProperties;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.context.ApplicationContext;
@@ -37,6 +40,8 @@ import org.springframework.context.ApplicationContextAware;
 @SuppressWarnings("rawtypes")
 public class FlowControllerFactoryBean implements FactoryBean, ApplicationContextAware {
 
+    private static final Logger LOG = LoggerFactory.getLogger(FlowControllerFactoryBean.class);
+
     private ApplicationContext applicationContext;
     private FlowController flowController;
     private NiFiProperties properties;
@@ -45,6 +50,7 @@ public class FlowControllerFactoryBean implements FactoryBean, ApplicationContex
     private StringEncryptor encryptor;
     private BulletinRepository bulletinRepository;
     private ClusterCoordinator clusterCoordinator;
+    private VariableRegistry variableRegistry;
 
     @Override
     public Object getObject() throws Exception {
@@ -63,7 +69,7 @@ public class FlowControllerFactoryBean implements FactoryBean, ApplicationContex
                     nodeProtocolSender,
                     bulletinRepository,
                     clusterCoordinator,
-                    heartbeatMonitor);
+                    heartbeatMonitor, variableRegistry);
             } else {
                 flowController = FlowController.createStandaloneInstance(
                     flowFileEventRepository,
@@ -71,7 +77,7 @@ public class FlowControllerFactoryBean implements FactoryBean, ApplicationContex
                     authorizer,
                     auditService,
                     encryptor,
-                    bulletinRepository);
+                    bulletinRepository, variableRegistry);
             }
 
         }
@@ -79,6 +85,8 @@ public class FlowControllerFactoryBean implements FactoryBean, ApplicationContex
         return flowController;
     }
 
+
+
     @Override
     public Class getObjectType() {
         return FlowController.class;
@@ -114,6 +122,10 @@ public class FlowControllerFactoryBean implements FactoryBean, ApplicationContex
         this.bulletinRepository = bulletinRepository;
     }
 
+    public void setVariableRegistry(VariableRegistry variableRegistry) {
+        this.variableRegistry = variableRegistry;
+    }
+
     public void setClusterCoordinator(final ClusterCoordinator clusterCoordinator) {
         this.clusterCoordinator = clusterCoordinator;
     }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/main/resources/nifi-context.xml

@@ -27,6 +27,11 @@
     <!-- nifi properties created via getInstance using a file path specified as a system property -->
     <bean id="nifiProperties" class="org.apache.nifi.util.NiFiProperties" factory-method="getInstance"/>
 
+    <!-- variable registry -->
+    <bean id="variableRegistry" class="org.apache.nifi.registry.VariableRegistryUtils" factory-method="createCustomVariableRegistry">
+        <constructor-arg type="java.nio.file.Path[]" value="#{nifiProperties.getVariableRegistryPropertiesPaths()}" />
+    </bean>
+
     <!-- flow file event repository -->
     <bean id="flowFileEventRepository" class="org.apache.nifi.spring.RingBufferEventRepositoryBean">
     </bean>
@@ -41,6 +46,7 @@
         <property name="encryptor" ref="stringEncryptor" />
         <property name="bulletinRepository" ref="bulletinRepository" />
         <property name="clusterCoordinator" ref="clusterCoordinator" />
+        <property name="variableRegistry" ref="variableRegistry"/>
     </bean>
 
     <!-- flow service -->

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/StandardFlowServiceTest.java

@@ -26,6 +26,8 @@ import org.apache.nifi.controller.serialization.FlowSerializer;
 import org.apache.nifi.controller.serialization.StandardFlowSerializer;
 import org.apache.nifi.encrypt.StringEncryptor;
 import org.apache.nifi.events.VolatileBulletinRepository;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.NiFiProperties;
 import org.apache.nifi.web.api.dto.ConnectableDTO;
 import org.apache.nifi.web.api.dto.ConnectionDTO;
@@ -63,6 +65,7 @@ public class StandardFlowServiceTest {
     private AuditService mockAuditService;
     private StringEncryptor mockEncryptor;
     private RevisionManager revisionManager;
+    private VariableRegistry variableRegistry;
 
     @BeforeClass
     public static void setupSuite() {
@@ -72,11 +75,13 @@ public class StandardFlowServiceTest {
     @Before
     public void setup() throws Exception {
         properties = NiFiProperties.getInstance();
+        variableRegistry = VariableRegistryUtils.createCustomVariableRegistry(properties.getVariableRegistryPropertiesPaths());
         mockFlowFileEventRepository = mock(FlowFileEventRepository.class);
         authorizer = mock(Authorizer.class);
         mockAuditService = mock(AuditService.class);
         revisionManager = mock(RevisionManager.class);
-        flowController = FlowController.createStandaloneInstance(mockFlowFileEventRepository, properties, authorizer, mockAuditService, mockEncryptor, new VolatileBulletinRepository());
+        flowController = FlowController.createStandaloneInstance(mockFlowFileEventRepository, properties, authorizer, mockAuditService, mockEncryptor,
+                                        new VolatileBulletinRepository(), variableRegistry);
         flowService = StandardFlowService.createStandaloneInstance(flowController, properties, mockEncryptor, revisionManager, authorizer);
     }
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/TestFlowController.java

@@ -33,6 +33,8 @@ import org.apache.nifi.controller.service.ControllerServiceNode;
 import org.apache.nifi.encrypt.StringEncryptor;
 import org.apache.nifi.processor.Relationship;
 import org.apache.nifi.provenance.MockProvenanceRepository;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.reporting.BulletinRepository;
 import org.apache.nifi.util.NiFiProperties;
 import org.junit.After;
@@ -61,6 +63,7 @@ public class TestFlowController {
     private StringEncryptor encryptor;
     private NiFiProperties properties;
     private BulletinRepository bulletinRepo;
+    private VariableRegistry variableRegistry;
 
     @Before
     public void setup() {
@@ -111,9 +114,10 @@ public class TestFlowController {
         policies1.add(policy2);
 
         authorizer = new MockPolicyBasedAuthorizer(groups1, users1, policies1);
+        variableRegistry = VariableRegistryUtils.createCustomVariableRegistry(properties.getVariableRegistryPropertiesPaths());
 
         bulletinRepo = Mockito.mock(BulletinRepository.class);
-        controller = FlowController.createStandaloneInstance(flowFileEventRepo, properties, authorizer, auditService, encryptor, bulletinRepo);
+        controller = FlowController.createStandaloneInstance(flowFileEventRepo, properties, authorizer, auditService, encryptor, bulletinRepo,variableRegistry);
 
         standardFlowSynchronizer = new StandardFlowSynchronizer(StringEncryptor.createEncryptor());
     }
@@ -165,7 +169,7 @@ public class TestFlowController {
         assertNotEquals(authFingerprint, authorizer.getFingerprint());
 
         controller.shutdown(true);
-        controller = FlowController.createStandaloneInstance(flowFileEventRepo, properties, authorizer, auditService, encryptor, bulletinRepo);
+        controller = FlowController.createStandaloneInstance(flowFileEventRepo, properties, authorizer, auditService, encryptor, bulletinRepo,variableRegistry);
         controller.synchronize(standardFlowSynchronizer, proposedDataFlow);
         assertEquals(authFingerprint, authorizer.getFingerprint());
     }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/scheduling/TestProcessorLifecycle.java

@@ -43,6 +43,7 @@ import org.apache.nifi.processor.ProcessSession;
 import org.apache.nifi.processor.Relationship;
 import org.apache.nifi.processor.exception.ProcessException;
 import org.apache.nifi.provenance.MockProvenanceRepository;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.NiFiProperties;
 import org.junit.After;
 import org.junit.Before;
@@ -661,7 +662,8 @@ public class TestProcessorLifecycle {
         properties.setProperty("nifi.remote.input.secure", "");
 
         return FlowController.createStandaloneInstance(mock(FlowFileEventRepository.class), properties,
-            mock(Authorizer.class), mock(AuditService.class), null, new VolatileBulletinRepository());
+            mock(Authorizer.class), mock(AuditService.class), null, new VolatileBulletinRepository(),
+                VariableRegistryUtils.createCustomVariableRegistry(properties.getVariableRegistryPropertiesPaths()));
     }
 
     /**

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/scheduling/TestStandardProcessScheduler.java

@@ -61,6 +61,8 @@ import org.apache.nifi.processor.ProcessSession;
 import org.apache.nifi.processor.Processor;
 import org.apache.nifi.processor.StandardValidationContextFactory;
 import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.reporting.AbstractReportingTask;
 import org.apache.nifi.reporting.InitializationException;
 import org.apache.nifi.reporting.ReportingContext;
@@ -76,6 +78,7 @@ public class TestStandardProcessScheduler {
     private ReportingTaskNode taskNode = null;
     private TestReportingTask reportingTask = null;
     private final StateManagerProvider stateMgrProvider = Mockito.mock(StateManagerProvider.class);
+    private VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     private FlowController controller;
     private ProcessGroup rootGroup;
 
@@ -83,7 +86,7 @@ public class TestStandardProcessScheduler {
     public void setup() throws InitializationException {
         System.setProperty("nifi.properties.file.path", "src/test/resources/nifi.properties");
         this.refreshNiFiProperties();
-        scheduler = new StandardProcessScheduler(Mockito.mock(ControllerServiceProvider.class), null, stateMgrProvider);
+        scheduler = new StandardProcessScheduler(Mockito.mock(ControllerServiceProvider.class), null, stateMgrProvider,variableRegistry);
         scheduler.setSchedulingAgent(SchedulingStrategy.TIMER_DRIVEN, Mockito.mock(SchedulingAgent.class));
 
         reportingTask = new TestReportingTask();
@@ -91,8 +94,8 @@ public class TestStandardProcessScheduler {
             Mockito.mock(ComponentLog.class), null);
         reportingTask.initialize(config);
 
-        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(null);
+        final ValidationContextFactory validationContextFactory = new StandardValidationContextFactory(null, variableRegistry);
-        taskNode = new StandardReportingTaskNode(reportingTask, UUID.randomUUID().toString(), null, scheduler, validationContextFactory);
+        taskNode = new StandardReportingTaskNode(reportingTask, UUID.randomUUID().toString(), null, scheduler, validationContextFactory, variableRegistry);
 
         controller = Mockito.mock(FlowController.class);
         rootGroup = new MockProcessGroup();
@@ -127,12 +130,12 @@ public class TestStandardProcessScheduler {
     public void testDisableControllerServiceWithProcessorTryingToStartUsingIt() throws InterruptedException {
         final Processor proc = new ServiceReferencingProcessor();
 
-        final StandardControllerServiceProvider serviceProvider = new StandardControllerServiceProvider(controller, scheduler, null, Mockito.mock(StateManagerProvider.class));
+        final StandardControllerServiceProvider serviceProvider = new StandardControllerServiceProvider(controller, scheduler, null, Mockito.mock(StateManagerProvider.class),variableRegistry);
         final ControllerServiceNode service = serviceProvider.createControllerService(NoStartServiceImpl.class.getName(), "service", true);
         rootGroup.addControllerService(service);
 
         final ProcessorNode procNode = new StandardProcessorNode(proc, UUID.randomUUID().toString(),
-                new StandardValidationContextFactory(serviceProvider), scheduler, serviceProvider);
+                new StandardValidationContextFactory(serviceProvider, variableRegistry), scheduler, serviceProvider);
         rootGroup.addProcessor(procNode);
 
         procNode.setProperty(ServiceReferencingProcessor.SERVICE_DESC.getName(), service.getIdentifier());
@@ -211,7 +214,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateServiceEnablementLogicHappensOnlyOnce() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider,variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(SimpleTestService.class.getName(),
                 "1", false);
         assertFalse(serviceNode.isActive());
@@ -250,7 +253,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateDisabledServiceCantBeDisabled() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider, variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(SimpleTestService.class.getName(),
                 "1", false);
         final SimpleTestService ts = (SimpleTestService) serviceNode.getControllerServiceImplementation();
@@ -288,7 +291,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateEnabledServiceCanOnlyBeDisabledOnce() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider,variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(SimpleTestService.class.getName(),
                 "1", false);
         final SimpleTestService ts = (SimpleTestService) serviceNode.getControllerServiceImplementation();
@@ -322,7 +325,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateDisablingOfTheFailedService() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider, variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(FailingService.class.getName(),
                 "1", false);
         scheduler.enableControllerService(serviceNode);
@@ -353,7 +356,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateEnabledDisableMultiThread() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider, variableRegistry);
         final ExecutorService executor = Executors.newCachedThreadPool();
         for (int i = 0; i < 200; i++) {
             final ControllerServiceNode serviceNode = provider
@@ -396,7 +399,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateNeverEnablingServiceCanStillBeDisabled() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider,variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(LongEnablingService.class.getName(),
                 "1", false);
         final LongEnablingService ts = (LongEnablingService) serviceNode.getControllerServiceImplementation();
@@ -421,7 +424,7 @@ public class TestStandardProcessScheduler {
     @Test
     public void validateLongEnablingServiceCanStillBeDisabled() throws Exception {
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateMgrProvider, variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(LongEnablingService.class.getName(),
                 "1", false);
         final LongEnablingService ts = (LongEnablingService) serviceNode.getControllerServiceImplementation();
@@ -518,6 +521,6 @@ public class TestStandardProcessScheduler {
     }
 
     private ProcessScheduler createScheduler() {
-        return new StandardProcessScheduler(null, null, stateMgrProvider);
+        return new StandardProcessScheduler(null, null, stateMgrProvider, variableRegistry);
     }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/service/StandardControllerServiceProviderTest.java

@@ -22,6 +22,8 @@ import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.StandardFlowServiceTest;
 import org.apache.nifi.nar.ExtensionManager;
 import org.apache.nifi.nar.NarClassLoaders;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.reporting.InitializationException;
 import org.apache.nifi.util.NiFiProperties;
 import org.junit.Before;
@@ -33,6 +35,7 @@ public class StandardControllerServiceProviderTest {
 
     private ControllerService proxied;
     private ControllerService implementation;
+    private static VariableRegistry variableRegistry;
 
     @BeforeClass
     public static void setupSuite() throws Exception {
@@ -40,6 +43,7 @@ public class StandardControllerServiceProviderTest {
         NiFiProperties properties = NiFiProperties.getInstance();
         NarClassLoaders.getInstance().init(properties.getFrameworkWorkingDirectory(), properties.getExtensionsWorkingDirectory());
         ExtensionManager.discoverExtensions(NarClassLoaders.getInstance().getExtensionClassLoaders());
+        variableRegistry = VariableRegistryUtils.createCustomVariableRegistry(properties.getVariableRegistryPropertiesPaths());
     }
 
     @Before
@@ -67,7 +71,7 @@ public class StandardControllerServiceProviderTest {
             @Override
             public void onComponentRemoved(String componentId) {
             }
-        });
+        }, variableRegistry);
         ControllerServiceNode node = provider.createControllerService(clazz, id, true);
         proxied = node.getProxiedControllerService();
         implementation = node.getControllerServiceImplementation();

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/service/TestStandardControllerServiceProvider.java

@@ -1,3 +1,4 @@
+
 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
@@ -45,6 +46,8 @@ import org.apache.nifi.controller.service.mock.ServiceC;
 import org.apache.nifi.groups.ProcessGroup;
 import org.apache.nifi.groups.StandardProcessGroup;
 import org.apache.nifi.processor.StandardValidationContextFactory;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -74,13 +77,15 @@ public class TestStandardControllerServiceProvider {
         }
     };
 
+    private static VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
+
     @BeforeClass
     public static void setNiFiProps() {
         System.setProperty("nifi.properties.file.path", "src/test/resources/nifi.properties");
     }
 
     private StandardProcessScheduler createScheduler() {
-        return new StandardProcessScheduler(null, null, stateManagerProvider);
+        return new StandardProcessScheduler(null, null, stateManagerProvider,variableRegistry);
     }
 
     @Test
@@ -90,7 +95,7 @@ public class TestStandardControllerServiceProvider {
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider,variableRegistry);
 
         final ControllerServiceNode serviceNode = provider.createControllerService(ServiceB.class.getName(), "B", false);
         provider.enableControllerService(serviceNode);
@@ -104,7 +109,7 @@ public class TestStandardControllerServiceProvider {
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(group);
 
         final ProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider,variableRegistry);
 
         final ControllerServiceNode serviceNodeB = provider.createControllerService(ServiceB.class.getName(), "B", false);
         final ControllerServiceNode serviceNodeA = provider.createControllerService(ServiceA.class.getName(), "A", false);
@@ -163,7 +168,7 @@ public class TestStandardControllerServiceProvider {
         final FlowController controller = Mockito.mock(FlowController.class);
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider,variableRegistry);
 
         // build a graph of controller services with dependencies as such:
         //
@@ -215,7 +220,7 @@ public class TestStandardControllerServiceProvider {
         final FlowController controller = Mockito.mock(FlowController.class);
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, null, null, stateManagerProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, null, null, stateManagerProvider,variableRegistry);
         final ControllerServiceNode serviceNode1 = provider.createControllerService(ServiceA.class.getName(), "1", false);
         final ControllerServiceNode serviceNode2 = provider.createControllerService(ServiceB.class.getName(), "2", false);
 
@@ -359,9 +364,9 @@ public class TestStandardControllerServiceProvider {
 
     private ProcessorNode createProcessor(final StandardProcessScheduler scheduler, final ControllerServiceProvider serviceProvider) {
         final ProcessorNode procNode = new StandardProcessorNode(new DummyProcessor(), UUID.randomUUID().toString(),
-                new StandardValidationContextFactory(serviceProvider), scheduler, serviceProvider);
+                new StandardValidationContextFactory(serviceProvider, null), scheduler, serviceProvider);
 
-        final ProcessGroup group = new StandardProcessGroup(UUID.randomUUID().toString(), serviceProvider, scheduler, null, null, null);
+        final ProcessGroup group = new StandardProcessGroup(UUID.randomUUID().toString(), serviceProvider, scheduler, null, null, null, variableRegistry);
         group.addProcessor(procNode);
         procNode.setProcessGroup(group);
 
@@ -375,7 +380,7 @@ public class TestStandardControllerServiceProvider {
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
         final StandardProcessScheduler scheduler = createScheduler();
-        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, null, null, stateManagerProvider);
+        final StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, null, null, stateManagerProvider,variableRegistry);
         final ControllerServiceNode serviceNode = provider.createControllerService(ServiceA.class.getName(), "1", false);
 
         final ProcessorNode procNode = createProcessor(scheduler, provider);
@@ -394,7 +399,7 @@ public class TestStandardControllerServiceProvider {
     public void validateEnableServices() {
         StandardProcessScheduler scheduler = createScheduler();
         FlowController controller = Mockito.mock(FlowController.class);
-        StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider);
+        StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider,variableRegistry);
         ProcessGroup procGroup = new MockProcessGroup();
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
@@ -439,7 +444,7 @@ public class TestStandardControllerServiceProvider {
         StandardProcessScheduler scheduler = createScheduler();
         FlowController controller = Mockito.mock(FlowController.class);
         StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null,
-                stateManagerProvider);
+                stateManagerProvider, variableRegistry);
         ProcessGroup procGroup = new MockProcessGroup();
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 
@@ -475,7 +480,7 @@ public class TestStandardControllerServiceProvider {
     public void validateEnableServicesWithDisabledMissingService() {
         StandardProcessScheduler scheduler = createScheduler();
         FlowController controller = Mockito.mock(FlowController.class);
-        StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider);
+        StandardControllerServiceProvider provider = new StandardControllerServiceProvider(controller, scheduler, null, stateManagerProvider,variableRegistry);
         ProcessGroup procGroup = new MockProcessGroup();
         Mockito.when(controller.getGroup(Mockito.anyString())).thenReturn(procGroup);
 

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/state/providers/local/TestWriteAheadLocalStateProvider.java

@@ -32,6 +32,8 @@ import org.apache.nifi.components.state.StateProvider;
 import org.apache.nifi.components.state.StateProviderInitializationContext;
 import org.apache.nifi.controller.state.StateMapUpdate;
 import org.apache.nifi.controller.state.providers.AbstractTestStateProvider;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.After;
 import org.junit.Before;
 import org.wali.WriteAheadRepository;
@@ -43,9 +45,9 @@ public class TestWriteAheadLocalStateProvider extends AbstractTestStateProvider
     @Before
     public void setup() throws IOException {
         provider = new WriteAheadLocalStateProvider();
-
+        final VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
         final Map<PropertyDescriptor, PropertyValue> properties = new HashMap<>();
-        properties.put(WriteAheadLocalStateProvider.PATH, new StandardPropertyValue("target/local-state-provider/" + UUID.randomUUID().toString(), null));
+        properties.put(WriteAheadLocalStateProvider.PATH, new StandardPropertyValue("target/local-state-provider/" + UUID.randomUUID().toString(), null, variableRegistry));
 
         provider.initialize(new StateProviderInitializationContext() {
             @Override
@@ -62,7 +64,7 @@ public class TestWriteAheadLocalStateProvider extends AbstractTestStateProvider
             public PropertyValue getProperty(final PropertyDescriptor property) {
                 final PropertyValue prop = properties.get(property);
                 if (prop == null) {
-                    return new StandardPropertyValue(null, null);
+                    return new StandardPropertyValue(null, null, variableRegistry);
                 }
                 return prop;
             }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/controller/state/providers/zookeeper/TestZooKeeperStateProvider.java

@@ -31,6 +31,8 @@ import org.apache.nifi.components.state.StateProvider;
 import org.apache.nifi.components.state.StateProviderInitializationContext;
 import org.apache.nifi.components.state.exception.StateTooLargeException;
 import org.apache.nifi.controller.state.providers.AbstractTestStateProvider;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -40,6 +42,7 @@ public class TestZooKeeperStateProvider extends AbstractTestStateProvider {
 
     private StateProvider provider;
     private TestingServer zkServer;
+    private VariableRegistry variableRegistry;
 
     private static final Map<PropertyDescriptor, String> defaultProperties = new HashMap<>();
 
@@ -58,6 +61,7 @@ public class TestZooKeeperStateProvider extends AbstractTestStateProvider {
         final Map<PropertyDescriptor, String> properties = new HashMap<>(defaultProperties);
         properties.put(ZooKeeperStateProvider.CONNECTION_STRING, zkServer.getConnectString());
         this.provider = createProvider(properties);
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     }
 
     private void initializeProvider(final ZooKeeperStateProvider provider, final Map<PropertyDescriptor, String> properties) throws IOException {
@@ -71,7 +75,7 @@ public class TestZooKeeperStateProvider extends AbstractTestStateProvider {
             public Map<PropertyDescriptor, PropertyValue> getProperties() {
                 final Map<PropertyDescriptor, PropertyValue> propValueMap = new HashMap<>();
                 for (final Map.Entry<PropertyDescriptor, String> entry : properties.entrySet()) {
-                    propValueMap.put(entry.getKey(), new StandardPropertyValue(entry.getValue(), null));
+                    propValueMap.put(entry.getKey(), new StandardPropertyValue(entry.getValue(), null, variableRegistry));
                 }
                 return propValueMap;
             }
@@ -79,7 +83,7 @@ public class TestZooKeeperStateProvider extends AbstractTestStateProvider {
             @Override
             public PropertyValue getProperty(final PropertyDescriptor property) {
                 final String prop = properties.get(property);
-                return new StandardPropertyValue(prop, null);
+                return new StandardPropertyValue(prop, null, variableRegistry);
             }
 
             @Override

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-framework-core/src/test/java/org/apache/nifi/processor/TestStandardPropertyValue.java

@@ -29,15 +29,19 @@ import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.ControllerServiceLookup;
 import org.apache.nifi.controller.repository.StandardFlowFileRecord;
 import org.apache.nifi.flowfile.FlowFile;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.junit.Test;
 
+
 public class TestStandardPropertyValue {
 
     private final ControllerServiceLookup lookup = new TestControllerServiceLookup();
+    private final VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
 
     @Test
     public void testSubstituteAttributesWithOneMatchingArg() {
-        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("audience", "World");
         assertEquals("Hello, World!", value.evaluateAttributeExpressions(createFlowFile(attributes)).getValue());
@@ -45,7 +49,7 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testMissingEndBraceEvaluatesToStringLiteral() {
-        final PropertyValue value = new StandardPropertyValue("Hello, ${audience!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, ${audience!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("audience", "World");
         assertEquals("Hello, ${audience!", value.evaluateAttributeExpressions(createFlowFile(attributes)).getValue());
@@ -53,7 +57,7 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testEscaped() {
-        final PropertyValue value = new StandardPropertyValue("Hello, $${audience}!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, $${audience}!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("audience", "World");
         assertEquals("Hello, ${audience}!", value.evaluateAttributeExpressions(createFlowFile(attributes)).getValue());
@@ -61,7 +65,7 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testSubstituteAttributesWithMultipleMatchingArgs() {
-        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}${comma}${question}!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}${comma}${question}!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("audience", "World");
         attributes.put("comma", ",");
@@ -71,14 +75,14 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testSubstituteAttributesWithNoMatch() {
-        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}${comma}${question:replaceNull('')}!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, ${audience}${comma}${question:replaceNull('')}!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         assertEquals("Hello, !", value.evaluateAttributeExpressions(createFlowFile(attributes)).getValue());
     }
 
     @Test
     public void testSubstituteAttributesRecursively() {
-        final PropertyValue value = new StandardPropertyValue("Hello, ${'${a}${b}'}!", lookup);
+        final PropertyValue value = new StandardPropertyValue("Hello, ${'${a}${b}'}!", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("a", "b");
         attributes.put("b", "World");
@@ -88,7 +92,7 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testGetValueAsIntegerAfterSubstitute() {
-        final PropertyValue value = new StandardPropertyValue("1${value}", lookup);
+        final PropertyValue value = new StandardPropertyValue("1${value}", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("value", "39");
         assertEquals(139, value.evaluateAttributeExpressions(createFlowFile(attributes)).asInteger().intValue());
@@ -96,7 +100,7 @@ public class TestStandardPropertyValue {
 
     @Test(expected = NumberFormatException.class)
     public void testGetValueAsIntegerAfterSubstitutingWithNonInteger() {
-        final PropertyValue value = new StandardPropertyValue("1${value}", lookup);
+        final PropertyValue value = new StandardPropertyValue("1${value}", lookup, variableRegistry);
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("value", "Yes");
         final PropertyValue substituted = value.evaluateAttributeExpressions(createFlowFile(attributes));
@@ -105,7 +109,7 @@ public class TestStandardPropertyValue {
 
     @Test
     public void testFileSize() {
-        final PropertyValue value = new StandardPropertyValue("${fileSize}", lookup);
+        final PropertyValue value = new StandardPropertyValue("${fileSize}", lookup, variableRegistry);
         final FlowFile flowFile = new StandardFlowFileRecord.Builder().size(1024 * 1024L).build();
         final long val = value.evaluateAttributeExpressions(flowFile).asLong().longValue();
         assertEquals(1024 * 1024L, val);
@@ -115,7 +119,7 @@ public class TestStandardPropertyValue {
     public void testFlowFileEntryYear() {
         final Calendar now = Calendar.getInstance();
         final int year = now.get(Calendar.YEAR);
-        final PropertyValue value = new StandardPropertyValue("${entryDate:toNumber():toDate():format('yyyy')}", lookup);
+        final PropertyValue value = new StandardPropertyValue("${entryDate:toNumber():toDate():format('yyyy')}", lookup, variableRegistry);
         final FlowFile flowFile = new StandardFlowFileRecord.Builder().entryDate(now.getTimeInMillis()).build();
         final int val = value.evaluateAttributeExpressions(flowFile).asInteger().intValue();
         assertEquals(year, val);
@@ -125,7 +129,7 @@ public class TestStandardPropertyValue {
     public void testSystemProperty() {
         System.setProperty("Prop1", "Foo");
         System.setProperty("Prop2", "Bar");
-        final PropertyValue value = new StandardPropertyValue("${Prop1}${Prop2}${abc}", lookup);
+        final PropertyValue value = new StandardPropertyValue("${Prop1}${Prop2}${abc}", lookup, VariableRegistryUtils.createSystemVariableRegistry());
         final Map<String, String> attributes = new HashMap<>();
         attributes.put("abc", "Baz");
         final FlowFile flowFile = createFlowFile(attributes);
@@ -171,5 +175,6 @@ public class TestStandardPropertyValue {
         public boolean isControllerServiceEnabling(final String serviceIdentifier) {
             return false;
         }
+
     }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-resources/src/main/resources/conf/nifi.properties

@@ -185,3 +185,7 @@ nifi.kerberos.krb5.file=${nifi.kerberos.krb5.file}
 nifi.kerberos.service.principal=${nifi.kerberos.service.principal}
 nifi.kerberos.keytab.location=${nifi.kerberos.keytab.location}
 nifi.kerberos.authentication.expiration=${nifi.kerberos.authentication.expiration}
+
+# external properties files for variable registry
+# supports a comma delimited list of file locations
+nifi.variable.registry.properties=

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-web/nifi-web-api/src/main/java/org/apache/nifi/web/StandardNiFiWebConfigurationContext.java

@@ -44,6 +44,7 @@ import org.apache.nifi.cluster.manager.exception.NoClusterCoordinatorException;
 import org.apache.nifi.cluster.protocol.NodeIdentifier;
 import org.apache.nifi.controller.ControllerService;
 import org.apache.nifi.controller.reporting.ReportingTaskProvider;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.controller.service.ControllerServiceProvider;
 import org.apache.nifi.util.NiFiProperties;
 import org.apache.nifi.web.api.dto.ControllerServiceDTO;
@@ -91,6 +92,7 @@ public class StandardNiFiWebConfigurationContext implements NiFiWebConfiguration
     private ReportingTaskProvider reportingTaskProvider;
     private AuditService auditService;
     private Authorizer authorizer;
+    private VariableRegistry variableRegistry;
 
     private void authorizeFlowAccess(final NiFiUser user) {
         // authorize access
@@ -287,6 +289,11 @@ public class StandardNiFiWebConfigurationContext implements NiFiWebConfiguration
     }
 
 
+    @Override
+    public VariableRegistry getVariableRegistry() {
+        return this.variableRegistry;
+    }
+
     private NodeResponse replicate(final String method, final URI uri, final Object entity, final Map<String, String> headers) throws InterruptedException {
         final NodeIdentifier coordinatorNode = clusterCoordinator.getElectedActiveCoordinatorNode();
         if (coordinatorNode == null) {
@@ -885,4 +892,8 @@ public class StandardNiFiWebConfigurationContext implements NiFiWebConfiguration
     public void setAuthorizer(final Authorizer authorizer) {
         this.authorizer = authorizer;
     }
+
+    public void setVariableRegistry(final VariableRegistry variableRegistry){
+        this.variableRegistry = variableRegistry;
+    }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-web/nifi-web-api/src/main/java/org/apache/nifi/web/controller/ControllerFacade.java

@@ -78,6 +78,7 @@ import org.apache.nifi.provenance.search.QuerySubmission;
 import org.apache.nifi.provenance.search.SearchTerm;
 import org.apache.nifi.provenance.search.SearchTerms;
 import org.apache.nifi.provenance.search.SearchableField;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.remote.RootGroupPort;
 import org.apache.nifi.reporting.BulletinRepository;
 import org.apache.nifi.reporting.ReportingTask;
@@ -147,7 +148,7 @@ public class ControllerFacade implements Authorizable {
     // properties
     private NiFiProperties properties;
     private DtoFactory dtoFactory;
-
+    private VariableRegistry variableRegistry;
 
     /**
      * Returns the group id that contains the specified processor.
@@ -1503,6 +1504,8 @@ public class ControllerFacade implements Authorizable {
         return dto;
     }
 
+
+
     private ComponentSearchResultDTO search(final String searchStr, final ProcessorNode procNode) {
         final List<String> matches = new ArrayList<>();
         final Processor processor = procNode.getProcessor();
@@ -1572,8 +1575,7 @@ public class ControllerFacade implements Authorizable {
         if (processor instanceof Searchable) {
             final Searchable searchable = (Searchable) processor;
 
-            // prepare the search context
+            final SearchContext context = new StandardSearchContext(searchStr, procNode, flowController, variableRegistry);
-            final SearchContext context = new StandardSearchContext(searchStr, procNode, flowController);
 
             // search the processor using the appropriate thread context classloader
             try (final NarCloseable x = NarCloseable.withNarLoader()) {
@@ -1781,4 +1783,8 @@ public class ControllerFacade implements Authorizable {
     public void setBulletinRepository(BulletinRepository bulletinRepository) {
         this.bulletinRepository = bulletinRepository;
     }
+
+    public void setVariableRegistry(VariableRegistry variableRegistry) {
+        this.variableRegistry = variableRegistry;
+    }
 }

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-web/nifi-web-api/src/main/java/org/apache/nifi/web/controller/StandardSearchContext.java

@@ -23,6 +23,7 @@ import org.apache.nifi.components.PropertyDescriptor;
 import org.apache.nifi.components.PropertyValue;
 import org.apache.nifi.controller.ControllerServiceLookup;
 import org.apache.nifi.controller.ProcessorNode;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.search.SearchContext;
 
 /**
@@ -33,11 +34,13 @@ public class StandardSearchContext implements SearchContext {
     private final String searchTerm;
     private final ProcessorNode processorNode;
     private final ControllerServiceLookup controllerServiceLookup;
+    private final VariableRegistry variableRegistry;
 
-    public StandardSearchContext(final String searchTerm, final ProcessorNode processorNode, final ControllerServiceLookup controllerServiceLookup) {
+    public StandardSearchContext(final String searchTerm, final ProcessorNode processorNode, final ControllerServiceLookup controllerServiceLookup, VariableRegistry variableRegistry) {
         this.searchTerm = searchTerm;
         this.processorNode = processorNode;
         this.controllerServiceLookup = controllerServiceLookup;
+        this.variableRegistry = variableRegistry;
     }
 
     @Override
@@ -53,7 +56,7 @@ public class StandardSearchContext implements SearchContext {
     @Override
     public PropertyValue getProperty(PropertyDescriptor property) {
         final String configuredValue = processorNode.getProperty(property);
-        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, controllerServiceLookup, null);
+        return new StandardPropertyValue(configuredValue == null ? property.getDefaultValue() : configuredValue, controllerServiceLookup,variableRegistry);
     }
 
     @Override

nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-web/nifi-web-api/src/main/resources/nifi-web-api-context.xml

@@ -119,6 +119,7 @@
         <property name="authorizer" ref="authorizer"/>
         <property name="dtoFactory" ref="dtoFactory"/>
         <property name="bulletinRepository" ref="bulletinRepository"/>
+        <property name="variableRegistry" ref="variableRegistry"/>
     </bean>
     <bean id="authorizableLookup" class="org.apache.nifi.authorization.StandardAuthorizableLookup">
         <property name="controllerFacade" ref="controllerFacade"/>
@@ -176,6 +177,7 @@
         <property name="controllerServiceProvider" ref="controllerServiceProvider"/>
         <property name="reportingTaskProvider" ref="reportingTaskProvider"/>
         <property name="authorizer" ref="authorizer"/>
+        <property name="variableRegistry" ref="variableRegistry"/>
     </bean>
 
     <!-- rest endpoints -->

nifi-nar-bundles/nifi-ranger-bundle/nifi-ranger-plugin/src/test/java/org/apache/nifi/ranger/authorization/TestRangerNiFiAuthorizer.java

@@ -29,6 +29,8 @@ import org.apache.nifi.authorization.RequestAction;
 import org.apache.nifi.authorization.Resource;
 import org.apache.nifi.authorization.UserContextKeys;
 import org.apache.nifi.authorization.exception.AuthorizerCreationException;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.MockPropertyValue;
 import org.apache.nifi.util.NiFiProperties;
 import org.apache.ranger.plugin.policyengine.RangerAccessRequest;
@@ -64,6 +66,7 @@ public class TestRangerNiFiAuthorizer {
     private RangerBasePluginWithPolicies rangerBasePlugin;
     private AuthorizerConfigurationContext configurationContext;
     private NiFiProperties nifiProperties;
+    private VariableRegistry variableRegistry;
 
     private String serviceType = "nifiService";
     private String appId = "nifiAppId";
@@ -95,22 +98,23 @@ public class TestRangerNiFiAuthorizer {
 
         notAllowedResult = Mockito.mock(RangerAccessResult.class);
         when(notAllowedResult.getIsAllowed()).thenReturn(false);
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     }
 
     private AuthorizerConfigurationContext createMockConfigContext() {
         AuthorizerConfigurationContext configurationContext = Mockito.mock(AuthorizerConfigurationContext.class);
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_SECURITY_PATH_PROP)))
-                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-security.xml", null));
+                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-security.xml", null,variableRegistry));
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_AUDIT_PATH_PROP)))
-                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-audit.xml", null));
+                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-audit.xml", null,variableRegistry));
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_APP_ID_PROP)))
-                .thenReturn(new MockPropertyValue(appId, null));
+                .thenReturn(new MockPropertyValue(appId, null,variableRegistry));
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_SERVICE_TYPE_PROP)))
-                .thenReturn(new MockPropertyValue(serviceType, null));
+                .thenReturn(new MockPropertyValue(serviceType, null,variableRegistry));
 
         return configurationContext;
     }
@@ -126,7 +130,7 @@ public class TestRangerNiFiAuthorizer {
     @Test
     public void testKerberosEnabledWithoutKeytab() {
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_KERBEROS_ENABLED_PROP)))
-                .thenReturn(new MockPropertyValue("true", null));
+                .thenReturn(new MockPropertyValue("true", null,variableRegistry));
 
         nifiProperties = Mockito.mock(NiFiProperties.class);
         when(nifiProperties.getKerberosServicePrincipal()).thenReturn("");
@@ -146,7 +150,7 @@ public class TestRangerNiFiAuthorizer {
     @Test
     public void testKerberosEnabledWithoutPrincipal() {
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_KERBEROS_ENABLED_PROP)))
-                .thenReturn(new MockPropertyValue("true", null));
+                .thenReturn(new MockPropertyValue("true", null,variableRegistry));
 
         nifiProperties = Mockito.mock(NiFiProperties.class);
         when(nifiProperties.getKerberosKeytabLocation()).thenReturn("");
@@ -166,7 +170,7 @@ public class TestRangerNiFiAuthorizer {
     @Test
     public void testKerberosEnabledWithoutKeytabOrPrincipal() {
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_KERBEROS_ENABLED_PROP)))
-                .thenReturn(new MockPropertyValue("true", null));
+                .thenReturn(new MockPropertyValue("true", null,variableRegistry));
 
         nifiProperties = Mockito.mock(NiFiProperties.class);
         when(nifiProperties.getKerberosKeytabLocation()).thenReturn("");
@@ -200,7 +204,7 @@ public class TestRangerNiFiAuthorizer {
     @Test
     public void testKerberosEnabled() {
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_KERBEROS_ENABLED_PROP)))
-                .thenReturn(new MockPropertyValue("true", null));
+                .thenReturn(new MockPropertyValue("true", null,variableRegistry));
 
         nifiProperties = Mockito.mock(NiFiProperties.class);
         when(nifiProperties.getKerberosKeytabLocation()).thenReturn("test");
@@ -398,7 +402,7 @@ public class TestRangerNiFiAuthorizer {
 
         final String rangerAdminIdentity = "ranger-admin";
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_ADMIN_IDENTITY_PROP)))
-                .thenReturn(new MockPropertyValue(rangerAdminIdentity, null));
+                .thenReturn(new MockPropertyValue(rangerAdminIdentity, null,variableRegistry));
 
         rangerBasePlugin = Mockito.mock(RangerBasePluginWithPolicies.class);
         authorizer = new MockRangerNiFiAuthorizer(rangerBasePlugin);
@@ -446,10 +450,10 @@ public class TestRangerNiFiAuthorizer {
         final AuthorizerConfigurationContext configurationContext = Mockito.mock(AuthorizerConfigurationContext.class);
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_SECURITY_PATH_PROP)))
-                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-security.xml", null));
+                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-security.xml", null,variableRegistry));
 
         when(configurationContext.getProperty(eq(RangerNiFiAuthorizer.RANGER_AUDIT_PATH_PROP)))
-                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-audit.xml", null));
+                .thenReturn(new MockPropertyValue("src/test/resources/ranger/ranger-nifi-audit.xml", null,variableRegistry));
 
         Authorizer authorizer = new RangerNiFiAuthorizer();
         try {

nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/test/java/org/apache/nifi/processors/script/TestInvokeGroovy.java

@@ -18,6 +18,8 @@ package org.apache.nifi.processors.script;
 
 import org.apache.nifi.components.PropertyDescriptor;
 import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.MockFlowFile;
 import org.apache.nifi.util.MockProcessContext;
 import org.apache.nifi.util.MockProcessorInitializationContext;
@@ -37,9 +39,12 @@ import static org.junit.Assert.assertTrue;
 
 public class TestInvokeGroovy extends BaseScriptTest {
 
+    private VariableRegistry variableRegistry;
+
     @Before
     public void setup() throws Exception {
         super.setupInvokeScriptProcessor();
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     }
 
     /**
@@ -72,7 +77,7 @@ public class TestInvokeGroovy extends BaseScriptTest {
     @Test
     public void testScriptDefinedAttribute() throws Exception {
         InvokeScriptedProcessor processor = new InvokeScriptedProcessor();
-        MockProcessContext context = new MockProcessContext(processor);
+        MockProcessContext context = new MockProcessContext(processor, variableRegistry);
         MockProcessorInitializationContext initContext = new MockProcessorInitializationContext(processor, context);
 
         processor.initialize(initContext);
@@ -81,7 +86,7 @@ public class TestInvokeGroovy extends BaseScriptTest {
         context.setProperty(InvokeScriptedProcessor.SCRIPT_FILE, "target/test/resources/groovy/test_reader.groovy");
         context.setProperty(InvokeScriptedProcessor.MODULES, "target/test/resources/groovy");
         // State Manger is unused, and a null reference is specified
-        processor.customValidate(new MockValidationContext(context, null));
+        processor.customValidate(new MockValidationContext(context, null, variableRegistry));
         processor.setup(context);
 
         List<PropertyDescriptor> descriptors = processor.getSupportedPropertyDescriptors();
@@ -106,7 +111,7 @@ public class TestInvokeGroovy extends BaseScriptTest {
     @Test
     public void testScriptDefinedRelationship() throws Exception {
         InvokeScriptedProcessor processor = new InvokeScriptedProcessor();
-        MockProcessContext context = new MockProcessContext(processor);
+        MockProcessContext context = new MockProcessContext(processor, variableRegistry);
         MockProcessorInitializationContext initContext = new MockProcessorInitializationContext(processor, context);
 
         processor.initialize(initContext);
@@ -114,7 +119,7 @@ public class TestInvokeGroovy extends BaseScriptTest {
         context.setProperty(InvokeScriptedProcessor.SCRIPT_ENGINE, "Groovy");
         context.setProperty(InvokeScriptedProcessor.SCRIPT_FILE, "target/test/resources/groovy/test_reader.groovy");
         // State Manger is unused, and a null reference is specified
-        processor.customValidate(new MockValidationContext(context, null));
+        processor.customValidate(new MockValidationContext(context, null, variableRegistry));
         processor.setup(context);
 
         Set<Relationship> relationships = processor.getRelationships();

nifi-nar-bundles/nifi-site-to-site-reporting-bundle/nifi-site-to-site-reporting-task/src/test/java/org/apache/nifi/reporting/TestSiteToSiteProvenanceReportingTask.java

@@ -28,6 +28,7 @@ import org.apache.nifi.provenance.ProvenanceEventRecord;
 import org.apache.nifi.provenance.ProvenanceEventRepository;
 import org.apache.nifi.provenance.ProvenanceEventType;
 import org.apache.nifi.provenance.StandardProvenanceEventRecord;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.remote.Transaction;
 import org.apache.nifi.remote.TransferDirection;
 import org.apache.nifi.remote.client.SiteToSiteClient;
@@ -94,7 +95,7 @@ public class TestSiteToSiteProvenanceReportingTask {
             @Override
             public PropertyValue answer(final InvocationOnMock invocation) throws Throwable {
                 final PropertyDescriptor descriptor = invocation.getArgumentAt(0, PropertyDescriptor.class);
-                return new MockPropertyValue(properties.get(descriptor), null);
+                return new MockPropertyValue(properties.get(descriptor), null, VariableRegistryUtils.createSystemVariableRegistry());
             }
         }).when(context).getProperty(Mockito.any(PropertyDescriptor.class));
 

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/java/org/apache/nifi/processors/standard/TestRouteOnAttribute.java

@@ -26,6 +26,8 @@ import java.util.Map;
 
 import org.apache.nifi.components.ValidationResult;
 import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.state.MockStateManager;
 import org.apache.nifi.util.MockFlowFile;
 import org.apache.nifi.util.MockProcessContext;
@@ -36,10 +38,12 @@ import org.junit.Test;
 
 public class TestRouteOnAttribute {
 
+    private VariableRegistry variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
+
     @Test
     public void testInvalidOnMisconfiguredProperty() {
         final RouteOnAttribute proc = new RouteOnAttribute();
-        final MockProcessContext ctx = new MockProcessContext(proc, new MockStateManager(proc));
+        final MockProcessContext ctx = new MockProcessContext(proc, new MockStateManager(proc), variableRegistry);
         final ValidationResult validationResult = ctx.setProperty("RouteA", "${a:equals('b')"); // Missing closing brace
         assertFalse(validationResult.isValid());
     }
@@ -47,7 +51,7 @@ public class TestRouteOnAttribute {
     @Test
     public void testInvalidOnNonBooleanProperty() {
         final RouteOnAttribute proc = new RouteOnAttribute();
-        final MockProcessContext ctx = new MockProcessContext(proc, new MockStateManager(proc));
+        final MockProcessContext ctx = new MockProcessContext(proc, new MockStateManager(proc), variableRegistry);
         final ValidationResult validationResult = ctx.setProperty("RouteA", "${a:length()"); // Should be boolean
         assertFalse(validationResult.isValid());
     }

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-reporting-tasks/src/test/java/org/apache/nifi/controller/MonitorMemoryTest.java

@@ -21,6 +21,7 @@ import org.apache.nifi.admin.service.AuditService;
 import org.apache.nifi.authorization.Authorizer;
 import org.apache.nifi.controller.repository.FlowFileEventRepository;
 import org.apache.nifi.provenance.MockProvenanceRepository;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.util.CapturingLogger;
 import org.apache.nifi.util.NiFiProperties;
 import org.junit.After;
@@ -136,6 +137,6 @@ public class MonitorMemoryTest {
         properties.setProperty("nifi.remote.input.secure", "");
 
         return FlowController.createStandaloneInstance(mock(FlowFileEventRepository.class), properties,
-                mock(Authorizer.class), mock(AuditService.class), null, null);
+                mock(Authorizer.class), mock(AuditService.class), null, null, VariableRegistryUtils.createCustomVariableRegistry(properties.getVariableRegistryPropertiesPaths()));
     }
 }

nifi-nar-bundles/nifi-standard-services/nifi-distributed-cache-services-bundle/nifi-distributed-cache-server/src/test/java/org/apache/nifi/distributed/cache/server/TestServerAndClient.java

@@ -41,6 +41,8 @@ import org.apache.nifi.distributed.cache.client.exception.DeserializationExcepti
 import org.apache.nifi.distributed.cache.server.map.DistributedMapCacheServer;
 import org.apache.nifi.processor.Processor;
 import org.apache.nifi.processor.util.StandardValidators;
+import org.apache.nifi.registry.VariableRegistry;
+import org.apache.nifi.registry.VariableRegistryUtils;
 import org.apache.nifi.reporting.InitializationException;
 import org.apache.nifi.util.MockConfigurationContext;
 import org.apache.nifi.util.MockControllerServiceInitializationContext;
@@ -55,6 +57,7 @@ import org.slf4j.LoggerFactory;
 public class TestServerAndClient {
 
     private static Logger LOGGER;
+    private static VariableRegistry variableRegistry;
 
     static {
         System.setProperty("org.slf4j.simpleLogger.defaultLogLevel", "info");
@@ -64,6 +67,7 @@ public class TestServerAndClient {
         System.setProperty("org.slf4j.simpleLogger.log.nifi.distributed.cache.server.TestServerAndClient", "debug");
         System.setProperty("org.slf4j.simpleLogger.log.nifi.remote.io.socket.ssl.SSLSocketChannel", "trace");
         LOGGER = LoggerFactory.getLogger(TestServerAndClient.class);
+        variableRegistry = VariableRegistryUtils.createSystemVariableRegistry();
     }
 
     @Test
@@ -329,7 +333,7 @@ public class TestServerAndClient {
         clientProperties.put(DistributedMapCacheClientService.HOSTNAME, "localhost");
         clientProperties.put(DistributedMapCacheClientService.PORT, String.valueOf(server.getPort()));
         clientProperties.put(DistributedMapCacheClientService.COMMUNICATIONS_TIMEOUT, "360 secs");
-        MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup());
+        MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup(), variableRegistry);
         client.cacheConfig(clientContext);
         final Serializer<String> valueSerializer = new StringSerializer();
         final Serializer<String> keySerializer = new StringSerializer();
@@ -375,7 +379,7 @@ public class TestServerAndClient {
         client2.initialize(clientInitContext2);
 
         MockConfigurationContext clientContext2 = new MockConfigurationContext(clientProperties,
-            clientInitContext2.getControllerServiceLookup());
+            clientInitContext2.getControllerServiceLookup(), variableRegistry);
         client2.cacheConfig(clientContext2);
         assertFalse(client2.putIfAbsent("testKey", "test", keySerializer, valueSerializer));
         assertTrue(client2.containsKey("testKey", keySerializer));
@@ -408,7 +412,7 @@ public class TestServerAndClient {
         server.initialize(serverInitContext);
 
         final Map<PropertyDescriptor, String> serverProperties = new HashMap<>();
-        final MockConfigurationContext serverContext = new MockConfigurationContext(serverProperties, serverInitContext.getControllerServiceLookup());
+        final MockConfigurationContext serverContext = new MockConfigurationContext(serverProperties, serverInitContext.getControllerServiceLookup(), variableRegistry);
         server.startServer(serverContext);
 
         DistributedMapCacheClientService client = new DistributedMapCacheClientService();
@@ -418,7 +422,7 @@ public class TestServerAndClient {
         final Map<PropertyDescriptor, String> clientProperties = new HashMap<>();
         clientProperties.put(DistributedMapCacheClientService.HOSTNAME, "localhost");
         clientProperties.put(DistributedMapCacheClientService.COMMUNICATIONS_TIMEOUT, "360 secs");
-        MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup());
+        MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup(), variableRegistry);
         client.cacheConfig(clientContext);
         final Serializer<String> valueSerializer = new StringSerializer();
         final Serializer<String> keySerializer = new StringSerializer();
@@ -465,7 +469,7 @@ public class TestServerAndClient {
         final Map<PropertyDescriptor, String> clientProperties = new HashMap<>();
         clientProperties.put(DistributedSetCacheClientService.HOSTNAME, "localhost");
         clientProperties.put(DistributedSetCacheClientService.PORT, String.valueOf(port));
-        final MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup());
+        final MockConfigurationContext clientContext = new MockConfigurationContext(clientProperties, clientInitContext.getControllerServiceLookup(), variableRegistry);
         client.onConfigured(clientContext);
 
         return client;

nifi-nar-bundles/nifi-update-attribute-bundle/nifi-update-attribute-ui/src/main/java/org/apache/nifi/update/attributes/UpdateAttributeModelFactory.java

@@ -23,6 +23,7 @@ import org.apache.nifi.attribute.expression.language.Query;
 import org.apache.nifi.attribute.expression.language.StandardExpressionLanguageCompiler;
 import org.apache.nifi.attribute.expression.language.exception.AttributeExpressionLanguageParsingException;
 import org.apache.nifi.expression.AttributeExpression.ResultType;
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.update.attributes.dto.ActionDTO;
 import org.apache.nifi.update.attributes.dto.ConditionDTO;
 import org.apache.nifi.update.attributes.dto.RuleDTO;
@@ -32,6 +33,12 @@ import org.apache.nifi.update.attributes.dto.RuleDTO;
  */
 public class UpdateAttributeModelFactory {
 
+    private final VariableRegistry variableRegistry;
+
+    public UpdateAttributeModelFactory(VariableRegistry variableRegistry) {
+        this.variableRegistry = variableRegistry;
+    }
+
     public Rule createRule(final RuleDTO dto) {
         if (dto == null) {
             throw new IllegalArgumentException("Rule must be specified.");
@@ -72,7 +79,7 @@ public class UpdateAttributeModelFactory {
         }
 
         // validate the condition's expression
-        final StandardExpressionLanguageCompiler elCompiler = new StandardExpressionLanguageCompiler();
+        final StandardExpressionLanguageCompiler elCompiler = new StandardExpressionLanguageCompiler(variableRegistry);
         final String syntaxError = elCompiler.validateExpression(dto.getExpression(), false);
         if (syntaxError != null) {
             throw new IllegalArgumentException(syntaxError);

nifi-nar-bundles/nifi-update-attribute-bundle/nifi-update-attribute-ui/src/main/java/org/apache/nifi/update/attributes/api/RuleResource.java

@@ -46,6 +46,7 @@ import javax.ws.rs.core.Response.ResponseBuilder;
 import javax.ws.rs.core.UriBuilder;
 import javax.ws.rs.core.UriInfo;
 
+import org.apache.nifi.registry.VariableRegistry;
 import org.apache.nifi.update.attributes.Action;
 import org.apache.nifi.update.attributes.Condition;
 import org.apache.nifi.update.attributes.Criteria;
@@ -187,6 +188,7 @@ public class RuleResource {
 
         // get the web context
         final NiFiWebConfigurationContext configurationContext = (NiFiWebConfigurationContext) servletContext.getAttribute("nifi-web-configuration-context");
+        final VariableRegistry variableRegistry = configurationContext.getVariableRegistry();
 
         // ensure the rule has been specified
         if (requestEntity == null || requestEntity.getRule() == null) {
@@ -219,7 +221,7 @@ public class RuleResource {
 
         // load the criteria
         final Criteria criteria = getCriteria(configurationContext, requestContext);
-        final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory();
+        final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory(variableRegistry);
 
         // create the new rule
         final Rule rule;
@@ -261,10 +263,14 @@ public class RuleResource {
         // generate a new id
         final String uuid = UUID.randomUUID().toString();
 
+        // get the variable registry
+        final NiFiWebConfigurationContext configurationContext = (NiFiWebConfigurationContext) servletContext.getAttribute("nifi-web-configuration-context");
+        final VariableRegistry variableRegistry = configurationContext.getVariableRegistry();
+
         final Condition condition;
         try {
             // create the condition object
-            final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory();
+            final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory(variableRegistry);
             condition = factory.createCondition(requestEntity.getCondition());
             condition.setId(uuid);
         } catch (final IllegalArgumentException iae) {
@@ -295,10 +301,14 @@ public class RuleResource {
         // generate a new id
         final String uuid = UUID.randomUUID().toString();
 
+        // get the variable registry
+        final NiFiWebConfigurationContext configurationContext = (NiFiWebConfigurationContext) servletContext.getAttribute("nifi-web-configuration-context");
+        final VariableRegistry variableRegistry = configurationContext.getVariableRegistry();
+
         final Action action;
         try {
             // create the condition object
-            final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory();
+            final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory(variableRegistry);
             action = factory.createAction(requestEntity.getAction());
             action.setId(uuid);
         } catch (final IllegalArgumentException iae) {
@@ -461,6 +471,8 @@ public class RuleResource {
 
         // get the web context
         final NiFiWebConfigurationContext nifiWebContext = (NiFiWebConfigurationContext) servletContext.getAttribute("nifi-web-configuration-context");
+        // get the variable registry
+        final VariableRegistry variableRegistry = nifiWebContext.getVariableRegistry();
 
         // ensure the rule has been specified
         if (requestEntity == null || requestEntity.getRule() == null) {
@@ -497,7 +509,7 @@ public class RuleResource {
                 requestEntity.getProcessorId(), requestEntity.getRevision(), requestEntity.getClientId());
 
         // load the criteria
-        final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory();
+        final UpdateAttributeModelFactory factory = new UpdateAttributeModelFactory(variableRegistry);
         final Criteria criteria = getCriteria(nifiWebContext, requestContext);
 
         // attempt to locate the rule