001/** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.camel.processor.saga; 018 019import java.util.concurrent.CompletableFuture; 020 021import org.apache.camel.AsyncCallback; 022import org.apache.camel.CamelContext; 023import org.apache.camel.Exchange; 024import org.apache.camel.Processor; 025import org.apache.camel.model.SagaCompletionMode; 026import org.apache.camel.processor.DelegateAsyncProcessor; 027import org.apache.camel.saga.CamelSagaCoordinator; 028import org.apache.camel.saga.CamelSagaService; 029import org.apache.camel.saga.CamelSagaStep; 030import org.apache.camel.util.ObjectHelper; 031 032/** 033 * Processor for handling sagas. 034 */ 035public abstract class SagaProcessor extends DelegateAsyncProcessor { 036 037 protected CamelContext camelContext; 038 039 protected CamelSagaService sagaService; 040 041 protected CamelSagaStep step; 042 043 protected SagaCompletionMode completionMode; 044 045 public SagaProcessor(CamelContext camelContext, Processor childProcessor, CamelSagaService sagaService, SagaCompletionMode completionMode, CamelSagaStep step) { 046 super(ObjectHelper.notNull(childProcessor, "childProcessor")); 047 this.camelContext = ObjectHelper.notNull(camelContext, "camelContext"); 048 this.sagaService = ObjectHelper.notNull(sagaService, "sagaService"); 049 this.completionMode = ObjectHelper.notNull(completionMode, "completionMode"); 050 this.step = ObjectHelper.notNull(step, "step"); 051 } 052 053 protected CompletableFuture<CamelSagaCoordinator> getCurrentSagaCoordinator(Exchange exchange) { 054 String currentSaga = exchange.getIn().getHeader(Exchange.SAGA_LONG_RUNNING_ACTION, String.class); 055 if (currentSaga != null) { 056 return sagaService.getSaga(currentSaga); 057 } 058 059 return CompletableFuture.completedFuture(null); 060 } 061 062 protected void setCurrentSagaCoordinator(Exchange exchange, CamelSagaCoordinator coordinator) { 063 if (coordinator != null) { 064 exchange.getIn().setHeader(Exchange.SAGA_LONG_RUNNING_ACTION, coordinator.getId()); 065 } else { 066 exchange.getIn().removeHeader(Exchange.SAGA_LONG_RUNNING_ACTION); 067 } 068 } 069 070 protected void handleSagaCompletion(Exchange exchange, CamelSagaCoordinator coordinator, CamelSagaCoordinator previousCoordinator, AsyncCallback callback) { 071 if (this.completionMode == SagaCompletionMode.AUTO) { 072 if (exchange.getException() != null) { 073 coordinator.compensate().whenComplete((done, ex) -> ifNotException(ex, exchange, callback, () -> { 074 setCurrentSagaCoordinator(exchange, previousCoordinator); 075 callback.done(false); 076 })); 077 } else { 078 coordinator.complete().whenComplete((done, ex) -> ifNotException(ex, exchange, callback, () -> { 079 setCurrentSagaCoordinator(exchange, previousCoordinator); 080 callback.done(false); 081 })); 082 } 083 } else if (this.completionMode == SagaCompletionMode.MANUAL) { 084 // Completion will be handled manually by the user 085 callback.done(false); 086 } else { 087 throw new IllegalStateException("Unsupported completion mode: " + this.completionMode); 088 } 089 } 090 091 public CamelSagaService getSagaService() { 092 return sagaService; 093 } 094 095 @Override 096 public String toString() { 097 return "saga"; 098 } 099 100 protected void ifNotException(Throwable ex, Exchange exchange, AsyncCallback callback, Runnable code) { 101 ifNotException(ex, exchange, false, null, null, callback, code); 102 } 103 104 protected void ifNotException(Throwable ex, Exchange exchange, boolean handleCompletion, CamelSagaCoordinator coordinator, 105 CamelSagaCoordinator previousCoordinator, AsyncCallback callback, Runnable code) { 106 if (ex != null) { 107 exchange.setException(ex); 108 if (handleCompletion) { 109 handleSagaCompletion(exchange, coordinator, previousCoordinator, callback); 110 } else { 111 callback.done(false); 112 } 113 } else { 114 code.run(); 115 } 116 } 117 118}