exceptionfactory commented on code in PR #7760: URL: https://github.com/apache/nifi/pull/7760#discussion_r1331639150
########## nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/PackageFlowFile.java: ########## @@ -0,0 +1,146 @@ +/* + * 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.standard; + +import org.apache.nifi.annotation.behavior.InputRequirement; +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.annotation.documentation.CapabilityDescription; +import org.apache.nifi.annotation.documentation.SeeAlso; +import org.apache.nifi.annotation.documentation.Tags; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.flowfile.attributes.CoreAttributes; +import org.apache.nifi.flowfile.attributes.StandardFlowFileMediaType; +import org.apache.nifi.processor.AbstractProcessor; +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.util.StandardValidators; +import org.apache.nifi.util.FlowFilePackager; +import org.apache.nifi.util.FlowFilePackagerV3; + +import java.io.BufferedInputStream; +import java.io.BufferedOutputStream; +import java.io.InputStream; +import java.io.OutputStream; +import java.util.Arrays; +import java.util.Collections; +import java.util.HashMap; +import java.util.LinkedHashSet; +import java.util.List; +import java.util.Map; +import java.util.Set; + + +@SideEffectFree +@SupportsBatching +@InputRequirement(InputRequirement.Requirement.INPUT_REQUIRED) +@Tags({"flowfile", "flowfile-stream", "flowfile-stream-v3", "package", "attributes"}) +@CapabilityDescription("This processor will package FlowFile attributes and content into an output FlowFile that can be exported from NiFi" + + " and imported back into NiFi, preserving the original attributes and content.") +@WritesAttributes({ + @WritesAttribute(attribute = "mime.type", description = "The mime.type will be changed to application/flowfile-v3"), + @WritesAttribute(attribute = "filename", description = "The filename will be appended with '.pkg'") +}) +@SeeAlso({UnpackContent.class, MergeContent.class}) +public class PackageFlowFile extends AbstractProcessor { + + static final String PACKAGE_FILENAME_EXTENSION = ".pkg"; + + public static final PropertyDescriptor BATCH_SIZE = new PropertyDescriptor.Builder() + .name("max-batch-size") + .displayName("Maximum Batch Size") + .description("Maximum number of FlowFiles to package into one output FlowFile using a best effort, non guaranteed approach." + + " Multiple input queues can produce unexpected batching behavior.") + .required(true) + .defaultValue("1") + .addValidator(StandardValidators.createLongValidator(1, 10_000, true)) + .build(); + + static final Relationship REL_SUCCESS = new Relationship.Builder() + .name("success") + .description("The packaged FlowFile is sent to this relationship") + .build(); + static final Relationship REL_ORIGINAL = new Relationship.Builder() + .name("original") + .description("The FlowFiles that were used to create the package are sent to this relationship") + .build(); + + private static final Set<Relationship> RELATIONSHIPS = Collections.unmodifiableSet( + new LinkedHashSet<>(Arrays.asList( + REL_SUCCESS, + REL_ORIGINAL + ))); + + private static final List<PropertyDescriptor> PROPERTY_DESCRIPTORS = Collections.unmodifiableList( + Arrays.asList( + BATCH_SIZE + )); + + @Override + public Set<Relationship> getRelationships() { + return RELATIONSHIPS; + } + + @Override + protected List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return PROPERTY_DESCRIPTORS; + } + + @Override + public void onTrigger(ProcessContext context, ProcessSession session) throws ProcessException { + final List<FlowFile> flowFiles = session.get(context.getProperty(BATCH_SIZE).asInteger()); + if (flowFiles.isEmpty()) { + return; + } + + final Map<String, String> attributes = new HashMap<>(); + attributes.put(CoreAttributes.MIME_TYPE.key(), StandardFlowFileMediaType.VERSION_3.getMediaType()); + attributes.put(CoreAttributes.FILENAME.key(), createFilename(flowFiles)); + + final FlowFilePackager packager = new FlowFilePackagerV3(); + + FlowFile packagedFlowFile = session.create(flowFiles); + packagedFlowFile = session.write(packagedFlowFile, out -> { + try (final OutputStream bufferedOut = new BufferedOutputStream(out)) { + for (final FlowFile flowFile : flowFiles) { + session.read(flowFile, in -> { + try (final InputStream bufferedIn = new BufferedInputStream(in)) { + packager.packageFlowFile(bufferedIn, bufferedOut, flowFile.getAttributes(), flowFile.getSize()); + } + }); + } + } + }); + + packagedFlowFile = session.putAllAttributes(packagedFlowFile, attributes); + session.transfer(packagedFlowFile, REL_SUCCESS); + session.transfer(flowFiles, REL_ORIGINAL); + } + + private String createFilename(final List<FlowFile> flowFiles) { Review Comment: For keeping the functionality simple, it may be better to leave the filename unchanged. A subsequent UpdateAttribute Processor could handle changes if needed. -- 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]
