NIFI-1077 enabling expression language on ConvertCharacterSet input and output

Signed-off-by: Mark Payne <markap14@hotmail.com>

nifi-commons/nifi-processor-utilities/src/main/java/org/apache/nifi/processor/util/StandardValidators.java

@@ -209,6 +209,16 @@ public class StandardValidators {
         @Override
         public ValidationResult validate(final String subject, final String value, final ValidationContext context) {
             if (context.isExpressionLanguageSupported(subject) && context.isExpressionLanguagePresent(value)) {
+                final ResultType resultType = context.newExpressionLanguageCompiler().getResultType(value);
+                if (!resultType.equals(ResultType.STRING)) {
+                    return new ValidationResult.Builder()
+                            .subject(subject)
+                            .input(value)
+                            .valid(false)
+                            .explanation("Expected Attribute Query to return type " + ResultType.STRING + " but query returns type " + resultType)
+                            .build();
+                }
+
                 return new ValidationResult.Builder().subject(subject).input(value).explanation("Expression Language Present").valid(true).build();
             }
 

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

@@ -23,6 +23,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
+
 import org.apache.nifi.processor.ProcessContext;
 import org.apache.nifi.processor.AbstractProcessor;
 import org.apache.nifi.processor.ProcessorInitializationContext;
@@ -87,12 +88,14 @@ public class ConvertCharacterSet extends AbstractProcessor {
     public static final PropertyDescriptor INPUT_CHARSET = new PropertyDescriptor.Builder()
             .name("Input Character Set")
             .description("The name of the CharacterSet to expect for Input")
+            .expressionLanguageSupported(true)
             .addValidator(StandardValidators.CHARACTER_SET_VALIDATOR)
             .required(true)
             .build();
     public static final PropertyDescriptor OUTPUT_CHARSET = new PropertyDescriptor.Builder()
             .name("Output Character Set")
             .description("The name of the CharacterSet to convert to")
+            .expressionLanguageSupported(true)
             .addValidator(StandardValidators.CHARACTER_SET_VALIDATOR)
             .required(true)
             .build();
@@ -128,10 +131,15 @@ public class ConvertCharacterSet extends AbstractProcessor {
 
     @Override
     public void onTrigger(final ProcessContext context, final ProcessSession session) {
+        FlowFile flowFile = session.get();
+        if (flowFile == null) {
+            return;
+        }
+
         final ProcessorLog logger = getLogger();
 
-        final Charset inputCharset = Charset.forName(context.getProperty(INPUT_CHARSET).getValue());
+        final Charset inputCharset = Charset.forName(context.getProperty(INPUT_CHARSET).evaluateAttributeExpressions(flowFile).getValue());
-        final Charset outputCharset = Charset.forName(context.getProperty(OUTPUT_CHARSET).getValue());
+        final Charset outputCharset = Charset.forName(context.getProperty(OUTPUT_CHARSET).evaluateAttributeExpressions(flowFile).getValue());
         final CharBuffer charBuffer = CharBuffer.allocate(MAX_BUFFER_SIZE);
 
         final CharsetDecoder decoder = inputCharset.newDecoder();
@@ -144,11 +152,6 @@ public class ConvertCharacterSet extends AbstractProcessor {
         encoder.onUnmappableCharacter(CodingErrorAction.REPLACE);
         encoder.replaceWith("?".getBytes(outputCharset));
 
-        FlowFile flowFile = session.get();
-        if (flowFile == null) {
-            return;
-        }
-
         try {
             final StopWatch stopWatch = new StopWatch(true);
             flowFile = session.write(flowFile, new StreamCallback() {
@@ -169,7 +172,7 @@ public class ConvertCharacterSet extends AbstractProcessor {
 
             session.getProvenanceReporter().modifyContent(flowFile, stopWatch.getElapsed(TimeUnit.MILLISECONDS));
             logger.info("successfully converted characters from {} to {} for {}",
-                    new Object[]{context.getProperty(INPUT_CHARSET).getValue(), context.getProperty(OUTPUT_CHARSET).getValue(), flowFile});
+                    new Object[]{inputCharset, outputCharset, flowFile});
             session.transfer(flowFile, REL_SUCCESS);
         } catch (final Exception e) {
             throw new ProcessException(e);

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

@@ -19,16 +19,20 @@ package org.apache.nifi.processors.standard;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Paths;
+import java.util.HashMap;
+import java.util.Map;
 
 import org.apache.nifi.util.MockFlowFile;
 import org.apache.nifi.util.TestRunner;
 import org.apache.nifi.util.TestRunners;
 import org.junit.Test;
 
+import static junit.framework.TestCase.fail;
+
 public class TestConvertCharacterSet {
 
     @Test
-    public void test() throws IOException {
+    public void testSimple() throws IOException {
         final TestRunner runner = TestRunners.newTestRunner(new ConvertCharacterSet());
         runner.setProperty(ConvertCharacterSet.INPUT_CHARSET, "ASCII");
         runner.setProperty(ConvertCharacterSet.OUTPUT_CHARSET, "UTF-32");
@@ -41,4 +45,62 @@ public class TestConvertCharacterSet {
         output.assertContentEquals(new File("src/test/resources/CharacterSetConversionSamples/Converted2.txt"));
     }
 
+    @Test
+    public void testExpressionLanguageInput() throws IOException {
+        final TestRunner runner = TestRunners.newTestRunner(new ConvertCharacterSet());
+        runner.setProperty(ConvertCharacterSet.INPUT_CHARSET, "${characterSet}");
+        runner.setProperty(ConvertCharacterSet.OUTPUT_CHARSET, "UTF-32");
+
+        final Map<String, String> attributes = new HashMap<>();
+        attributes.put("characterSet", "ASCII");
+        runner.enqueue(Paths.get("src/test/resources/CharacterSetConversionSamples/Original.txt"),attributes);
+        runner.run();
+
+        runner.assertAllFlowFilesTransferred(ConvertCharacterSet.REL_SUCCESS, 1);
+        final MockFlowFile output = runner.getFlowFilesForRelationship(ConvertCharacterSet.REL_SUCCESS).get(0);
+        output.assertContentEquals(new File("src/test/resources/CharacterSetConversionSamples/Converted2.txt"));
+    }
+
+    @Test
+    public void testExpressionLanguageOutput() throws IOException {
+        final TestRunner runner = TestRunners.newTestRunner(new ConvertCharacterSet());
+        runner.setProperty(ConvertCharacterSet.INPUT_CHARSET, "ASCII");
+        runner.setProperty(ConvertCharacterSet.OUTPUT_CHARSET, "${characterSet}");
+
+        final Map<String, String> attributes = new HashMap<>();
+        attributes.put("characterSet", "UTF-32");
+        runner.enqueue(Paths.get("src/test/resources/CharacterSetConversionSamples/Original.txt"),attributes);
+        runner.run();
+
+        runner.assertAllFlowFilesTransferred(ConvertCharacterSet.REL_SUCCESS, 1);
+        final MockFlowFile output = runner.getFlowFilesForRelationship(ConvertCharacterSet.REL_SUCCESS).get(0);
+        output.assertContentEquals(new File("src/test/resources/CharacterSetConversionSamples/Converted2.txt"));
+    }
+
+    @Test
+    public void testExpressionLanguageConfig() throws IOException {
+        final TestRunner runner = TestRunners.newTestRunner(new ConvertCharacterSet());
+        runner.setProperty(ConvertCharacterSet.INPUT_CHARSET, "${now()}");
+        runner.setProperty(ConvertCharacterSet.OUTPUT_CHARSET, "UTF-32");
+
+        runner.enqueue(Paths.get("src/test/resources/CharacterSetConversionSamples/Original.txt"));
+        try {
+            runner.run();
+            fail("Should fail to validate config and fail to run the on trigger");
+        } catch (AssertionError e){
+            // Expect to fail assertion for passing a date to the character set validator
+        }
+
+
+        runner.setProperty(ConvertCharacterSet.INPUT_CHARSET, "UTF-32");
+        runner.setProperty(ConvertCharacterSet.OUTPUT_CHARSET, "${anyAttribute(\"abc\", \"xyz\"):contains(\"bye\")}");
+
+        runner.enqueue(Paths.get("src/test/resources/CharacterSetConversionSamples/Original.txt"));
+        try {
+            runner.run();
+            fail("Should fail to validate config and fail to run the on trigger");
+        } catch (AssertionError e) {
+            // Expect to fail assertion for passing a boolean to the character set validator
+        }
+    }
 }