dan-s1 commented on code in PR #8691: URL: https://github.com/apache/nifi/pull/8691#discussion_r1601826244
########## nifi-extension-bundles/nifi-network-bundle/nifi-network-processors/src/main/java/org/apache/nifi/processors/network/SplitPCAP.java: ########## @@ -0,0 +1,184 @@ +/* + * 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.network; + +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.annotation.behavior.WritesAttribute; +import org.apache.nifi.annotation.documentation.CapabilityDescription; +import org.apache.nifi.annotation.documentation.Tags; +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.util.StandardValidators; +import org.apache.nifi.processors.network.util.PCAP; +import org.apache.nifi.processors.network.util.PCAP.ByteBufferInterface; +import org.apache.nifi.processors.network.util.PCAP.Packet; + +import java.io.ByteArrayOutputStream; +import java.util.ArrayList; +import java.util.List; +import java.util.Set; + +@Tags({"PCAP", "Splitter", "Network", "Packet", "Capture", "Wireshark", "TShark"}) +@CapabilityDescription("Splits a pcap file into multiple pcap files based on a maximum size.") +@WritesAttribute(attribute = SplitPCAP.ERROR_REASON, description = "The reason the flowfile was sent to the failure relationship.") + +public class SplitPCAP extends AbstractProcessor { + + protected static final String ERROR_REASON = "ERROR_REASON"; + + public static final PropertyDescriptor PCAP_MAX_SIZE = new PropertyDescriptor + .Builder().name("PCAP_MAX_SIZE") + .displayName("PCAP max size (bytes)") + .description("Maximum size of the output pcap file in bytes.") + .required(true) + .addValidator(StandardValidators.INTEGER_VALIDATOR) + .build(); + + public static final Relationship REL_SUCCESS = new Relationship.Builder() + .name("success") + .description("output flowfiles") + .build(); + + public static final Relationship REL_FAILURE = new Relationship.Builder() + .name("failure") + .description("Flowfiles not parseable as pcap.") + .build(); + + private static final List<PropertyDescriptor> DESCRIPTORS = List.of(PCAP_MAX_SIZE); + + private static final Set<Relationship> RELATIONSHIPS = Set.of(REL_SUCCESS, REL_FAILURE); + + @Override + public Set<Relationship> getRelationships() { + return RELATIONSHIPS; + } + + @Override + public final List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return DESCRIPTORS; + } + + /** + * This method is called when a trigger event occurs in the processor. + * It processes the incoming flow file, splits it into smaller pcap files based on the maximum size, + * and transfers the split pcap files to the success relationship. + * If the flow file is empty or not parseable, it is transferred to the failure relationship. + * + * @param context the process context + * @param session the process session + */ + @Override + public void onTrigger(final ProcessContext context, final ProcessSession session) { + FlowFile flowFile = session.get(); + if (flowFile == null) { + return; + } + + int pcapMaxSize = context.getProperty(PCAP_MAX_SIZE.getName()).asInteger(); + + final ByteArrayOutputStream contentBytes = new ByteArrayOutputStream(); + session.exportTo(flowFile, contentBytes); + final byte[] contentByteArray = contentBytes.toByteArray(); + + if(contentByteArray.length == 0){ + session.putAttribute(flowFile,ERROR_REASON, "PCAP file empty."); + session.transfer(flowFile, REL_FAILURE); + return; + } + + PCAP parsedPcap; + PCAP templatePcap; + + // Parse the pcap file and create a template pcap object to borrow the header from. + try{ + parsedPcap = new PCAP(new ByteBufferInterface(contentByteArray)); + + // Recreating rather than using deepcopy as recreating is more efficient in this case. + templatePcap = new PCAP(new ByteBufferInterface(contentByteArray)); + + } catch (Exception e){ + session.putAttribute(flowFile,ERROR_REASON, "PCAP file not parseable."); + session.transfer(flowFile, REL_FAILURE); + return; + } + + var unprocessedPackets = parsedPcap.packets(); + + int currentPacketCollectionSize = 0; + int totalFlowfileCount = 1; + int packetHeaderLength = 24; + + ArrayList<Packet> newPackets = new ArrayList<>(); + templatePcap.packets().clear(); + + + // Loop through all packets in the pcap file and split them into smaller pcap files. + while (!unprocessedPackets.isEmpty()){ + var packet = unprocessedPackets.get(0); + + if (packet.inclLen() > pcapMaxSize){ + session.putAttribute(flowFile,ERROR_REASON, "PCAP contains a packet larger than the max size."); + session.transfer(flowFile, REL_FAILURE); + return; + } + + if (currentPacketCollectionSize + (packet.inclLen() + packetHeaderLength) > pcapMaxSize && currentPacketCollectionSize > 0){ + templatePcap.packets().addAll(newPackets); + var newFlowFile = session.create(flowFile); + + session.write(newFlowFile, out -> out.write(templatePcap.readBytesFull())); + + session.putAttribute( + newFlowFile, + "filename", + flowFile.getAttribute("filename").split("\\.")[0] + "-" + totalFlowfileCount + ".pcap" + ); + + session.transfer(newFlowFile, REL_SUCCESS); + totalFlowfileCount += 1; + + newPackets = new ArrayList<>(); + currentPacketCollectionSize = 0; + templatePcap.packets().clear(); + + } else { + newPackets.add(packet); + currentPacketCollectionSize += ((int) packet.inclLen() + packetHeaderLength); + unprocessedPackets.remove(0); + } + } + + // If there are any packets left over, create a new flowfile. + if(!newPackets.isEmpty()){ + templatePcap.packets().addAll(newPackets); + var newFlowFile = session.create(flowFile); + session.putAttribute( + newFlowFile, + "filename", + flowFile.getAttribute("filename").split("\\.")[0] + "-" + totalFlowfileCount + ".pcap" + ); Review Comment: All of the split processors (SplitAvro, SplitContent, SplitXml, SplitJson and SplitRecord) make use of the `org.apache.nifi.flowfile.attributes.FragmentAttributes` enum found in the `nifi-utils` module which is already included in the `pom.xml` for `nifi-network-processors`. Please see the aforementioned processors to see how the enum is used and please include them in `@WritesAttribute` as seen in those processor files. -- 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]
