NIFI-601: Add Dynamic Props - ExecuteStreamCommand

- Added dynamic property support to ExecuteStreamCommand. All
  properties added by user will be inserted into the command's
  runtime environment.

Signed-off-by: Aldrin Piri <aldrin@apache.org>

nifi/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/pom.xml

@@ -248,6 +248,7 @@
                         <exclude>src/test/resources/CompressedData/SampleFileConcat.txt.bz2</exclude>
                         <exclude>src/test/resources/ExecuteCommand/TestIngestAndUpdate.jar</exclude>
                         <exclude>src/test/resources/ExecuteCommand/TestSuccess.jar</exclude>
+                        <exclude>src/test/resources/ExecuteCommand/TestDynamicEnvironment.jar</exclude>
                         <exclude>src/test/resources/TestIdentifyMimeType/1.jar</exclude>
                         <exclude>src/test/resources/TestIdentifyMimeType/1.tar</exclude>
                         <exclude>src/test/resources/TestIdentifyMimeType/1.tar.gz</exclude>

nifi/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/ExecuteStreamCommand.java

@@ -33,6 +33,7 @@ import java.util.Set;
 
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.nifi.annotation.behavior.DynamicProperty;
 import org.apache.nifi.annotation.behavior.EventDriven;
 import org.apache.nifi.annotation.behavior.SupportsBatching;
 import org.apache.nifi.annotation.documentation.CapabilityDescription;
@@ -113,6 +114,7 @@ import org.apache.nifi.stream.io.StreamUtils;
 @SupportsBatching
 @Tags({"command execution", "command", "stream", "execute"})
 @CapabilityDescription("Executes an external command on the contents of a flow file, and creates a new flow file with the results of the command.")
+@DynamicProperty(name = "An environment variable name", value = "An environment variable value", description = "These environment variables are passed to the process spawned by this Processor")
 @WritesAttributes({
     @WritesAttribute(attribute = "execution.command", description = "The name of the command executed to create the new FlowFile"),
     @WritesAttribute(attribute = "execution.command.args", description = "The semi-colon delimited list of arguments"),
@@ -202,6 +204,16 @@ public class ExecuteStreamCommand extends AbstractProcessor {
         return PROPERTIES;
     }
 
+    @Override
+    protected PropertyDescriptor getSupportedDynamicPropertyDescriptor(final String propertyDescriptorName) {
+        return new PropertyDescriptor.Builder()
+        .name(propertyDescriptorName)
+        .description("Sets the environment variable '" + propertyDescriptorName + "' for the process' environment")
+        .dynamic(true)
+        .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+        .build();
+    }
+
     @Override
     public void onTrigger(ProcessContext context, final ProcessSession session) throws ProcessException {
         FlowFile flowFile = session.get();
@@ -230,6 +242,13 @@ public class ExecuteStreamCommand extends AbstractProcessor {
                 logger.warn("Failed to create working directory {}, using current working directory {}", new Object[]{workingDir, System.getProperty("user.dir")});
             }
         }
+        final Map<String, String> environment = new HashMap<>();
+        for (final Map.Entry<PropertyDescriptor, String> entry : context.getProperties().entrySet()) {
+            if (entry.getKey().isDynamic()) {
+                environment.put(entry.getKey().getName(), entry.getValue());
+            }
+        }
+        builder.environment().putAll(environment);
         builder.command(args);
         builder.directory(dir);
         builder.redirectInput(Redirect.PIPE);

nifi/nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/java/TestDynamicEnvironment.java

@@ -0,0 +1,29 @@
+/*
+ * 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.Map;
+
+public class TestDynamicEnvironment {
+    public static void main(String[] args) {
+        // iterate through current environment and print out all properties starting with NIFI
+        for (Map.Entry<String, String> env: System.getenv().entrySet()) {
+            if (env.getKey().startsWith("NIFI")) {
+                System.out.println(env.getKey() + "=" + env.getValue());
+            }
+        }
+    }
+}

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

@@ -182,4 +182,30 @@ public class TestExecuteStreamCommand {
         assertEquals(0, flowFiles.get(0).getSize());
 
     }
+
+    @Test
+    public void testDynamicEnvironment() throws Exception {
+        File exJar = new File("src/test/resources/ExecuteCommand/TestDynamicEnvironment.jar");
+        File dummy = new File("src/test/resources/ExecuteCommand/1000bytes.txt");
+        String jarPath = exJar.getAbsolutePath();
+        exJar.setExecutable(true);
+        final TestRunner controller = TestRunners.newTestRunner(ExecuteStreamCommand.class);
+        controller.setProperty("NIFI_TEST_1", "testvalue1");
+        controller.setProperty("NIFI_TEST_2", "testvalue2");
+        controller.setValidateExpressionUsage(false);
+        controller.enqueue(dummy.toPath());
+        controller.setProperty(ExecuteStreamCommand.WORKING_DIR, "target");
+        controller.setProperty(ExecuteStreamCommand.EXECUTION_COMMAND, "java");
+        controller.setProperty(ExecuteStreamCommand.EXECUTION_ARGUMENTS, "-jar;" + jarPath);
+        controller.run(1);
+        controller.assertTransferCount(ExecuteStreamCommand.ORIGINAL_RELATIONSHIP, 1);
+        controller.assertTransferCount(ExecuteStreamCommand.OUTPUT_STREAM_RELATIONSHIP, 1);
+        List<MockFlowFile> flowFiles = controller.getFlowFilesForRelationship(ExecuteStreamCommand.OUTPUT_STREAM_RELATIONSHIP);
+        byte[] byteArray = flowFiles.get(0).toByteArray();
+        String result = new String(byteArray);
+        String[] dynamicEnvironment = result.split("\n");
+        assertEquals("Should contain two environment variables starting with NIFI", 2, dynamicEnvironment.length);
+        assertEquals("NIFI_TEST_2 environment variable is missing", "NIFI_TEST_2=testvalue2", dynamicEnvironment[0]);
+        assertEquals("NIFI_TEST_1 environment variable is missing", "NIFI_TEST_1=testvalue1", dynamicEnvironment[1]);
+    }
 }