Lehel44 commented on a change in pull request #4948: URL: https://github.com/apache/nifi/pull/4948#discussion_r664075743
########## File path: nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/main/java/org/apache/nifi/processors/script/ScriptedRouterProcessor.java ########## @@ -0,0 +1,213 @@ +/* + * 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.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.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.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Optional; +import java.util.function.BiFunction; + +@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.count", description = "The number of records within the flow file."), + @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 { + 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 ScriptRunner scriptRunner = pollScriptRunner(); + if (scriptRunner == null) { + // This shouldn't happen. But just in case. + session.rollback(); + return; + } + + boolean success = false; + + try { + final ScriptEvaluator evaluator; + + try { + final ScriptEngine scriptEngine = scriptRunner.getScriptEngine(); + evaluator = createEvaluator(scriptEngine, flowFile); + } catch (final ScriptException se) { + getLogger().error("Failed to initialize script engine", se); + session.transfer(flowFile, getFailureRelationship()); + return; + } + + success = route(context, session, flowFile, evaluator); + } finally { + offerScriptRunner(scriptRunner); + } + + session.transfer(flowFile, success ? getOriginalRelationship() : getFailureRelationship()); + } + + 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() { Review comment: This could be replaced with lambda as well to be more compact. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
