AggregateABCRecoverTest.java

/**
 * 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 camelinaction;

import java.util.concurrent.TimeUnit;

import org.apache.camel.Exchange;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.component.hawtdb.HawtDBAggregationRepository;
import org.apache.camel.component.mock.MockEndpoint;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Test;

/**
 * The ABC example for using the Aggregator EIP.
 * <p/>
 * This example uses recovery to have the published messages being redelivered
 * in case processing failed.
 * <p/>
 * See the class {@link MyAggregationStrategy} for how the messages
 * are actually aggregated together.
 *
 * @see MyAggregationStrategy
 * @version $Revision: 130 $
 */
public class AggregateABCRecoverTest extends CamelTestSupport {

    @Override
    public void setUp() throws Exception {
        // ensure we use a fresh repo each time by deleting the data directory
        deleteDirectory("data");
        super.setUp();
    }

    @Test
    public void testABCRecover() throws Exception {
        // we should never get a result
        getMockEndpoint("mock:result").expectedMessageCount(0);

        MockEndpoint mock = getMockEndpoint("mock:aggregate");
        // we should try 1 time + 4 times as redelivery
        mock.expectedMessageCount(5);

        MockEndpoint dead = getMockEndpoint("mock:dead");
        // we should send the message to dead letter channel when exhausted
        dead.expectedBodiesReceived("ABC");
        // should be marked as redelivered
        dead.message(0).header(Exchange.REDELIVERED).isEqualTo(true);
        // and we did try 4 times to redeliver
        dead.message(0).header(Exchange.REDELIVERY_COUNTER).isEqualTo(4);

        // send the first message
        template.sendBodyAndHeader("direct:start", "A", "myId", 1);
        // send the 2nd message with the same correlation key
        template.sendBodyAndHeader("direct:start", "B", "myId", 1);
        // now we have 3 messages with the same correlation key
        // and the Aggregator should publish the message
        template.sendBodyAndHeader("direct:start", "C", "myId", 1);

        // wait for 20 seconds as this test takes some time
        assertMockEndpointsSatisfied(20, TimeUnit.SECONDS);
    }

    @Override
    protected RouteBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            @Override
            public void configure() throws Exception {
                HawtDBAggregationRepository hawtDB = new HawtDBAggregationRepository("myrepo", "data/myrepo.dat");
                // will recover by default
                hawtDB.setUseRecovery(true);
                // try at most 4 times
                hawtDB.setMaximumRedeliveries(4);
                // send to mock:dead if exhausted
                hawtDB.setDeadLetterUri("mock:dead");
                // have it retry every 3th second
                hawtDB.setRecoveryInterval(3000);

                from("direct:start")
                    // do a little logging
                    .log("Sending ${body} with correlation key ${header.myId}")
                    // aggregate based on header correlation key
                    // use class MyAggregationStrategy for aggregation
                    // and complete when we have aggregated 3 messages
                    .aggregate(header("myId"), new MyAggregationStrategy())
                        // use HawtDB as the persistent repository
                        .aggregationRepository(hawtDB)
                        // and complete when we got 3 messages
                        .completionSize(3)
                        // do a little logging for the published message
                        .log("Sending out ${body}")
                        // use a mock to check recovery
                        .to("mock:aggregate")
                        // force failure to have the message being recovered
                        .throwException(new IllegalArgumentException("Damn does not work"))
                        // and send it to the mock (not possible, due exception being thrown)
                        .to("mock:result");
            }
        };
    }
}