timeabarna commented on a change in pull request #4948: URL: https://github.com/apache/nifi/pull/4948#discussion_r639581961
########## File path: nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/main/java/org/apache/nifi/processors/script/ScriptedRouterProcessor.java ########## @@ -0,0 +1,267 @@ +/* + * 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.processors.script; + +import org.apache.nifi.annotation.behavior.EventDriven; +import org.apache.nifi.annotation.behavior.InputRequirement; +import org.apache.nifi.annotation.behavior.Restricted; +import org.apache.nifi.annotation.behavior.Restriction; +import org.apache.nifi.annotation.behavior.SideEffectFree; +import org.apache.nifi.annotation.behavior.SupportsBatching; +import org.apache.nifi.annotation.behavior.WritesAttribute; +import org.apache.nifi.annotation.behavior.WritesAttributes; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.components.RequiredPermission; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.processor.ProcessSession; +import org.apache.nifi.processor.Relationship; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.nifi.processor.io.InputStreamCallback; +import org.apache.nifi.schema.access.SchemaNotFoundException; +import org.apache.nifi.script.ScriptingComponentUtils; +import org.apache.nifi.serialization.MalformedRecordException; +import org.apache.nifi.serialization.RecordReader; +import org.apache.nifi.serialization.RecordReaderFactory; +import org.apache.nifi.serialization.RecordSetWriter; +import org.apache.nifi.serialization.RecordSetWriterFactory; +import org.apache.nifi.serialization.WriteResult; +import org.apache.nifi.serialization.record.ListRecordSet; +import org.apache.nifi.serialization.record.PushBackRecordSet; +import org.apache.nifi.serialization.record.Record; +import org.apache.nifi.serialization.record.RecordSchema; +import org.apache.nifi.serialization.record.RecordSet; + +import javax.script.ScriptEngine; +import javax.script.ScriptException; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; +import java.util.Arrays; +import java.util.HashMap; +import java.util.LinkedList; +import java.util.List; +import java.util.Map; +import java.util.Optional; + +@EventDriven +@SupportsBatching +@SideEffectFree +@InputRequirement(InputRequirement.Requirement.INPUT_REQUIRED) +@Restricted(restrictions = { + @Restriction(requiredPermission = RequiredPermission.EXECUTE_CODE, + explanation = "Provides operator the ability to execute arbitrary code assuming all permissions that NiFi has.") +}) +@WritesAttributes({ + @WritesAttribute(attribute = "mime.type", description = "Sets the mime.type attribute to the MIME Type specified by the Record Writer"), + @WritesAttribute(attribute = "record.error.message", description = "This attribute provides on failure the error message encountered by the Reader or Writer.") +}) +public abstract class ScriptedRouterProcessor<T> extends ScriptedProcessor { + + static final PropertyDescriptor RECORD_READER = new PropertyDescriptor.Builder() + .name("Record Reader") + .displayName("Record Reader") + .description("The Record Reader to use parsing the incoming FlowFile into Records") + .required(true) + .identifiesControllerService(RecordReaderFactory.class) + .build(); + + static final PropertyDescriptor RECORD_WRITER = new PropertyDescriptor.Builder() + .name("Record Writer") + .displayName("Record Writer") + .description("The Record Writer to use for serializing Records after they have been transformed") + .required(true) + .identifiesControllerService(RecordSetWriterFactory.class) + .build(); + + static final PropertyDescriptor LANGUAGE = new PropertyDescriptor.Builder() + .name("Script Engine") + .displayName("Script Language") + .description("The Language to use for the script") + .allowableValues(SCRIPT_OPTIONS) + .defaultValue("Groovy") + .required(true) + .build(); + + private static final List<PropertyDescriptor> DESCRIPTORS = Arrays.asList( + RECORD_READER, + RECORD_WRITER, + LANGUAGE, + ScriptingComponentUtils.SCRIPT_BODY, + ScriptingComponentUtils.SCRIPT_FILE, + ScriptingComponentUtils.MODULES); + + private final Class<T> scriptResultType; + + /** + * @param scriptResultType Defines the expected result type of the user-provided script. + */ + protected ScriptedRouterProcessor(final Class<T> scriptResultType) { + this.scriptResultType = scriptResultType; + } + + @Override + protected List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return DESCRIPTORS; + } + + @Override + public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException { + final FlowFile flowFile = session.get(); + if (flowFile == null) { + return; + } + + final ScriptEngine scriptEngine = pollScriptEngine(); + if (scriptEngine == null) { + // This shouldn't happen. But just in case. + session.rollback(); + return; + } + + boolean success = false; + + try { + final ScriptEvaluator evaluator; + + try { + evaluator = createEvaluator(scriptEngine, flowFile); + } catch (final ScriptException se) { + getLogger().error("Failed to initialize script engine", se); + session.transfer(flowFile, getFailedRelationship()); + return; + } + + success = route(context, session, flowFile, evaluator); + } finally { + offerScriptEngine(scriptEngine); + } + + session.transfer(flowFile, success ? getOriginalRelationship() : getFailedRelationship()); + } + + private boolean route( + final ProcessContext context, + final ProcessSession session, + final FlowFile incomingFlowFile, + final ScriptEvaluator evaluator + ) { + final RecordReaderFactory readerFactory = context.getProperty(RECORD_READER).asControllerService(RecordReaderFactory.class); + final RecordSetWriterFactory writerFactory = context.getProperty(RECORD_WRITER).asControllerService(RecordSetWriterFactory.class); + final Map<String, String> originalAttributes = incomingFlowFile.getAttributes(); + + try { + session.read(incomingFlowFile, new InputStreamCallback() { + @Override + public void process(final InputStream in) throws IOException { + try ( + final RecordReader reader = readerFactory.createRecordReader(originalAttributes, in, incomingFlowFile.getSize(), getLogger()) + ) { + final RecordSchema schema = writerFactory.getSchema(originalAttributes, reader.getSchema()); + final RecordSet recordSet = reader.createRecordSet(); + final PushBackRecordSet pushBackSet = new PushBackRecordSet(recordSet); + final Map<Relationship, List<Record>> outgoingRecords = new HashMap<>(); + int index = 0; + + // Reading in records and evaluate script + while (pushBackSet.isAnotherRecord()) { + final Record record = pushBackSet.next(); + final Object evaluatedValue = evaluator.evaluate(record, index++); + + if (evaluatedValue != null && scriptResultType.isInstance(evaluatedValue)) { + final Optional<Relationship> outgoingRelationship = resolveRelationship(scriptResultType.cast(evaluatedValue)); + + if (outgoingRelationship.isPresent()) { + if (!outgoingRecords.containsKey(outgoingRelationship.get())) { + outgoingRecords.put(outgoingRelationship.get(), new LinkedList<>()); + } + + outgoingRecords.get(outgoingRelationship.get()).add(record); + } else { + getLogger().debug("Record with evaluated value {} has no outgoing relationship determined", String.valueOf(evaluatedValue)); + } + } else { + throw new ProcessException("Script result is not applicable: " + String.valueOf(evaluatedValue)); + } + } + + // Creating and sending outgoing flow files + for (final Map.Entry<Relationship, List<Record>> entry : outgoingRecords.entrySet()) { + final Relationship relationship = entry.getKey(); + final List<Record> records = entry.getValue(); + + if (records.isEmpty()) { + getLogger().debug("No outgoing records for relationship {}", relationship.getName()); + continue; + } + + FlowFile outgoingFlowFile = session.create(incomingFlowFile); + final Map<String, String> attributesToAdd = new HashMap<>(); + + try ( + final OutputStream out = session.write(outgoingFlowFile); + final RecordSetWriter writer = writerFactory.createWriter(getLogger(), schema, out, outgoingFlowFile); + ) { + attributesToAdd.put("mime.type", writer.getMimeType()); + + if (records.size() == 1) { + final WriteResult writeResult = writer.write(records.get(0)); Review comment: WriteResult can be extracted before if, same in ScriptedTransformRecord class row 231. ########## File path: nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/main/java/org/apache/nifi/processors/script/ScriptEvaluator.java ########## @@ -0,0 +1,39 @@ +/* + * 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.processors.script; + +import org.apache.nifi.serialization.record.Record; + +import javax.script.ScriptException; + +/** + * Used by scripted record processors to enclose script engines for different languages. + */ +interface ScriptEvaluator { + + /** + * Evaluates the enclosed script using the record as arugment. Returns with the script's return value. Review comment: @simonbence Thank you very much for your contribution. I've got some minor stylistic findings worth checking. ########## File path: nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/main/java/org/apache/nifi/processors/script/ScriptEvaluator.java ########## @@ -0,0 +1,39 @@ +/* + * 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.processors.script; + +import org.apache.nifi.serialization.record.Record; + +import javax.script.ScriptException; + +/** + * Used by scripted record processors to enclose script engines for different languages. + */ +interface ScriptEvaluator { + + /** + * Evaluates the enclosed script using the record as arugment. Returns with the script's return value. Review comment: Typo in argument. -- This is an automated message from the Apache Git Service. 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