/**
* 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.camel.component.reactive.streams;
import io.reactivex.BackpressureStrategy;
import io.reactivex.Flowable;
import io.reactivex.Observable;
import org.apache.camel.RoutesBuilder;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.component.mock.MockEndpoint;
import org.apache.camel.component.reactive.streams.api.CamelReactiveStreams;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Test;
/**
* Test backpressure from the consumer side.
*/
public class BackpressureSubscriberTest extends CamelTestSupport {
@Test
public void testBackpressure() throws Exception {
long start = System.currentTimeMillis();
Observable.range(0, 10)
.toFlowable(BackpressureStrategy.BUFFER)
.subscribe(CamelReactiveStreams.get(context).streamSubscriber("slowNumbers", Integer.class));
MockEndpoint endpoint = getMockEndpoint("mock:endpoint");
endpoint.expectedMessageCount(10);
endpoint.assertIsSatisfied();
long end = System.currentTimeMillis();
// Maximum one inflight exchange, even if multiple consumer threads are present
// Must take at least 50 * 10 = 500ms
assertTrue("Exchange completed too early", end - start >= 500);
}
@Test
public void testSlowerBackpressure() throws Exception {
long start = System.currentTimeMillis();
Observable.range(0, 2)
.toFlowable(BackpressureStrategy.BUFFER)
.subscribe(CamelReactiveStreams.get(context).streamSubscriber("slowerNumbers", Integer.class));
MockEndpoint endpoint = getMockEndpoint("mock:endpoint");
endpoint.expectedMessageCount(2);
endpoint.assertIsSatisfied();
long end = System.currentTimeMillis();
// Maximum one inflight exchange, even if multiple consumer threads are present
// Must take at least 300 * 2 = 600ms
assertTrue("Exchange completed too early", end - start >= 600);
}
@Test
public void testParallelSlowBackpressure() throws Exception {
long start = System.currentTimeMillis();
Flowable.range(0, 40)
.subscribe(CamelReactiveStreams.get(context).streamSubscriber("parallelSlowNumbers", Integer.class));
MockEndpoint endpoint = getMockEndpoint("mock:endpoint");
endpoint.expectedMessageCount(40);
endpoint.assertIsSatisfied();
long end = System.currentTimeMillis();
// Maximum 5 inflight exchanges
// Must take at least 100 * (40 / 5) = 800ms
assertTrue("Exchange completed too early", end - start >= 800);
}
@Override
protected RoutesBuilder createRouteBuilder() throws Exception {
return new RouteBuilder() {
@Override
public void configure() throws Exception {
from("reactive-streams:slowNumbers?concurrentConsumers=10&maxInflightExchanges=1")
.process(x -> Thread.sleep(50))
.to("mock:endpoint");
from("reactive-streams:slowerNumbers?concurrentConsumers=10&maxInflightExchanges=1")
.process(x -> Thread.sleep(300))
.to("mock:endpoint");
from("reactive-streams:parallelSlowNumbers?concurrentConsumers=10&maxInflightExchanges=5")
.process(x -> Thread.sleep(100))
.to("mock:endpoint");
}
};
}
}