Lehel44 commented on a change in pull request #4948: URL: https://github.com/apache/nifi/pull/4948#discussion_r664013449
########## File path: nifi-nar-bundles/nifi-scripting-bundle/nifi-scripting-processors/src/main/java/org/apache/nifi/processors/script/ScriptedProcessor.java ########## @@ -0,0 +1,168 @@ +/* + * 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.commons.io.IOUtils; +import org.apache.nifi.annotation.lifecycle.OnScheduled; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.components.ValidationContext; +import org.apache.nifi.components.ValidationResult; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.processor.AbstractProcessor; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.script.ScriptingComponentHelper; +import org.apache.nifi.script.ScriptingComponentUtils; +import org.apache.nifi.search.SearchContext; +import org.apache.nifi.search.SearchResult; +import org.apache.nifi.search.Searchable; +import org.apache.nifi.serialization.RecordReaderFactory; +import org.apache.nifi.serialization.RecordSetWriterFactory; + +import javax.script.Bindings; +import javax.script.Compilable; +import javax.script.CompiledScript; +import javax.script.ScriptContext; +import javax.script.ScriptEngine; +import javax.script.ScriptException; +import javax.script.SimpleBindings; +import java.io.FileInputStream; +import java.io.IOException; +import java.nio.charset.Charset; +import java.util.Arrays; +import java.util.Collection; +import java.util.List; +import java.util.Set; +import java.util.concurrent.atomic.AtomicReference; + +abstract class ScriptedProcessor extends AbstractProcessor implements Searchable { + protected static final String PYTHON_SCRIPT_LANGUAGE = "python"; + protected static final Set<String> SCRIPT_OPTIONS = ScriptingComponentUtils.getAvailableEngines(); + + protected volatile String scriptToRun = null; + protected final AtomicReference<CompiledScript> compiledScriptRef = new AtomicReference<>(); + private final ScriptingComponentHelper scriptingComponentHelper = new ScriptingComponentHelper(); + + 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(); + + protected static final List<PropertyDescriptor> DESCRIPTORS = Arrays.asList( + RECORD_READER, + RECORD_WRITER, + LANGUAGE, + ScriptingComponentUtils.SCRIPT_BODY, + ScriptingComponentUtils.SCRIPT_FILE, + ScriptingComponentUtils.MODULES); + + + @OnScheduled + public void setup(final ProcessContext context) throws IOException { + if (!scriptingComponentHelper.isInitialized.get()) { + scriptingComponentHelper.createResources(false); + } + + scriptingComponentHelper.setupVariables(context); + scriptToRun = scriptingComponentHelper.getScriptBody(); + + if (scriptToRun == null && scriptingComponentHelper.getScriptPath() != null) { + try (final FileInputStream scriptStream = new FileInputStream(scriptingComponentHelper.getScriptPath())) { + scriptToRun = IOUtils.toString(scriptStream, Charset.defaultCharset()); + } + } + + // Create a script runner for each possible task + final int maxTasks = context.getMaxConcurrentTasks(); + scriptingComponentHelper.setupScriptRunners(maxTasks, scriptToRun, getLogger()); + + // Always compile when first run + compiledScriptRef.set(null); + } + + protected ScriptEvaluator createEvaluator(final ScriptEngine scriptEngine, final FlowFile flowFile) throws ScriptException { + if (PYTHON_SCRIPT_LANGUAGE.equalsIgnoreCase(scriptEngine.getFactory().getLanguageName())) { + final CompiledScript compiledScript = getOrCompileScript((Compilable) scriptEngine, scriptToRun); + return new PythonScriptEvaluator(scriptEngine, compiledScript, flowFile, getLogger()); + } + + return new InterpretedScriptEvaluator(scriptEngine, scriptToRun, flowFile, getLogger()); + } + + private CompiledScript getOrCompileScript(final Compilable scriptEngine, final String scriptToRun) throws ScriptException { + final CompiledScript existing = compiledScriptRef.get(); + if (existing != null) { + return existing; + } + + final CompiledScript compiled = scriptEngine.compile(scriptToRun); + final boolean updated = compiledScriptRef.compareAndSet(null, compiled); + if (updated) { + return compiled; + } + + return compiledScriptRef.get(); + } + + @Override + protected Collection<ValidationResult> customValidate(ValidationContext validationContext) { + return scriptingComponentHelper.customValidate(validationContext); + } + + @Override + public Collection<SearchResult> search(final SearchContext context) { + return ScriptingComponentUtils.search(context, getLogger()); + } + + protected static Bindings setupBindings(final ScriptEngine scriptEngine) { + Bindings bindings = scriptEngine.getBindings(ScriptContext.ENGINE_SCOPE); + if (bindings == null) { + bindings = new SimpleBindings(); + } + + scriptEngine.setBindings(bindings, ScriptContext.ENGINE_SCOPE); + + return bindings; + } + + protected ScriptRunner pollScriptRunner() { + return scriptingComponentHelper.scriptRunnerQ.poll(); + } + + protected void offerScriptRunner(ScriptRunner scriptRunner) { + scriptingComponentHelper.scriptRunnerQ.offer(scriptRunner); Review comment: Is it possible at any point that we cannot add the _scriptRunner_ to the queue? If so, should the _false_ return value of _offer_ get handled? -- 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]
