rkarthik29 commented on a change in pull request #3306: nifi oracle cdc changes using xstream URL: https://github.com/apache/nifi/pull/3306#discussion_r338264056
########## File path: nifi-nar-bundles/nifi-oraclecdc-bundle/nifi-oraclecdc-processors/src/main/java/org/apache/nifi/processors/oraclecdc/OracleChangeCapture.java ########## @@ -0,0 +1,251 @@ +/* + * 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.oraclecdc; + +import java.io.IOException; +import java.io.OutputStream; +import java.util.ArrayList; +import java.util.Collections; +import java.util.HashMap; +import java.util.HashSet; +import java.util.List; +import java.util.Set; + +import org.apache.commons.codec.binary.Base32; +import org.apache.nifi.annotation.behavior.InputRequirement; +import org.apache.nifi.annotation.behavior.InputRequirement.Requirement; +import org.apache.nifi.annotation.behavior.ReadsAttribute; +import org.apache.nifi.annotation.behavior.ReadsAttributes; +import org.apache.nifi.annotation.behavior.Stateful; +import org.apache.nifi.annotation.behavior.TriggerSerially; +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.annotation.lifecycle.OnScheduled; +import org.apache.nifi.annotation.lifecycle.OnShutdown; +import org.apache.nifi.annotation.lifecycle.OnStopped; +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.components.state.Scope; +import org.apache.nifi.components.state.StateManager; +import org.apache.nifi.components.state.StateMap; +import org.apache.nifi.dbcp.DBCPService; +import org.apache.nifi.flowfile.FlowFile; +import org.apache.nifi.processor.AbstractProcessor; +import org.apache.nifi.processor.ProcessContext; +import org.apache.nifi.processor.ProcessSession; +import org.apache.nifi.processor.ProcessorInitializationContext; +import org.apache.nifi.processor.Relationship; +import org.apache.nifi.processor.exception.ProcessException; +import org.apache.nifi.processor.io.OutputStreamCallback; +import org.apache.nifi.processor.util.StandardValidators; +import org.nifi.oraclecdcservice.api.OracleCDCEventHandler; +import org.nifi.oraclecdcservice.api.OracleCDCService; + +@TriggerSerially +@Tags({ "Oracle", "CDC", "change capture" }) +@CapabilityDescription("capture oracle CDC changes using xstream api. " + + "Look at this link to see how to setup xstream outbound server on oracle db" + + " https://github.com/rkarthik29/oracle_cdc/blob/master/README.md";) +@SeeAlso({}) +@InputRequirement(Requirement.INPUT_FORBIDDEN) +@ReadsAttributes({ @ReadsAttribute(attribute = "", description = "") }) +@WritesAttributes({ @WritesAttribute(attribute = "cdc_type", description = "provides the type of cdc operation, " + + "ex.INSERT,UPDATE,DELETE,COMMIT") }) +@Stateful(scopes = Scope.CLUSTER, description = "After receiving cdc events from the xstream out server " + + "the processor will store the last position received in the state map. " + + "It will be used to set the low watermark for the next call") + +public class OracleChangeCapture extends AbstractProcessor { + + public static final PropertyDescriptor XS_OUT = new PropertyDescriptor.Builder().name("XS_OUT") + .displayName("XStream Outbound Server Name").description("xout").required(true) + .addValidator(StandardValidators.NON_EMPTY_VALIDATOR).build(); + + public static final PropertyDescriptor CDC_SERVICE = new PropertyDescriptor.Builder() + .name("Oracle CDC connection pooling service") + .description("The Controller Service that is used to obtain connection to database").required(true) + .identifiesControllerService(OracleCDCService.class).build(); + + public static final Relationship INSERTS = new Relationship.Builder().name("INSERTS").description("CDC INSERTS") + .build(); + + public static final Relationship UPDATES = new Relationship.Builder().name("UPDATES").description("CDC UPDATES") + .build(); + + public static final Relationship DELETES = new Relationship.Builder().name("DELETES").description("CDC DELETES") + .build(); + public static final Relationship UNMATCHED = new Relationship.Builder().name("UNMATCHED") + .description("UNSUPPORTED OPERATION").build(); + + private List<PropertyDescriptor> descriptors; + + private Set<Relationship> relationships; + + protected DBCPService dbcpService; + + protected Object xsOut; + + private OracleCDCService cdcService; + + @Override + protected void init(final ProcessorInitializationContext context) { + final List<PropertyDescriptor> descriptors = new ArrayList<PropertyDescriptor>(); + descriptors.add(XS_OUT); + descriptors.add(CDC_SERVICE); + this.descriptors = Collections.unmodifiableList(descriptors); + + final Set<Relationship> relationships = new HashSet<Relationship>(); + relationships.add(INSERTS); + relationships.add(UPDATES); + relationships.add(DELETES); + relationships.add(UNMATCHED); + this.relationships = Collections.unmodifiableSet(relationships); + } + + @Override + public Set<Relationship> getRelationships() { + return this.relationships; + } + + @Override + public final List<PropertyDescriptor> getSupportedPropertyDescriptors() { + return descriptors; + } + + @OnScheduled + public void onScheduled(final ProcessContext context) { + byte[] position = null; + final StateManager stateManager = context.getStateManager(); + StateMap stateMap; + try { + stateMap = stateManager.getState(Scope.CLUSTER); + } catch (final IOException ioe) { + stateMap = null; + getLogger().warn("Failed to retrieve the low watermark from State Manager", ioe); + } + if (stateMap != null) { + System.out.println("position from statemap" + stateMap.get("positon")); + position = new Base32(true).decode(stateMap.get("positon")); + } + cdcService = context.getProperty(CDC_SERVICE).asControllerService(OracleCDCService.class); + String xsOutServerName = context.getProperty(XS_OUT).getValue(); + xsOut = cdcService.attach(xsOutServerName, position); + + } + + @OnShutdown + @OnStopped + public void shutdown(final ProcessContext context) { + cdcService.detach(xsOut); + } + + @Override + public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException { + CDCHandler handler = new CDCHandler(session); + cdcService.receiveEvents(xsOut, handler); + if (handler.isMoveMarker()) { + cdcService.setProcessedLowWaterMark(xsOut, handler.getLastPosition()); + + final StateManager stateManager = context.getStateManager(); + try { + HashMap<String, String> stateMap = new HashMap<String, String>(); + System.out.println( Review comment: removed it ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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