/*
* 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.cassandra.net;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;
import com.google.common.util.concurrent.AbstractFuture;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import junit.framework.AssertionFailedError;
/**
* Allows inspecting the behavior of mocked messaging by observing {@link MatcherResponse}.
*/
public class MockMessagingSpy
{
private static final Logger logger = LoggerFactory.getLogger(MockMessagingSpy.class);
public int messagesIntercepted = 0;
public int mockedMessageResponses = 0;
private final BlockingQueue<MessageOut<?>> interceptedMessages = new LinkedBlockingQueue<>();
private final BlockingQueue<MessageIn<?>> deliveredResponses = new LinkedBlockingQueue<>();
private static final Executor executor = Executors.newSingleThreadExecutor();
/**
* Returns a future with the first mocked incoming message that has been created and delivered.
*/
public ListenableFuture<MessageIn<?>> captureMockedMessageIn()
{
return Futures.transform(captureMockedMessageInN(1), (List<MessageIn<?>> result) -> result.isEmpty() ? null : result.get(0));
}
/**
* Returns a future with the specified number mocked incoming messages that have been created and delivered.
*/
public ListenableFuture<List<MessageIn<?>>> captureMockedMessageInN(int noOfMessages)
{
CapturedResultsFuture<MessageIn<?>> ret = new CapturedResultsFuture<>(noOfMessages, deliveredResponses);
executor.execute(ret);
return ret;
}
/**
* Returns a future that will indicate if a mocked incoming message has been created and delivered.
*/
public ListenableFuture<Boolean> expectMockedMessageIn()
{
return expectMockedMessageIn(1);
}
/**
* Returns a future that will indicate if the specified number of mocked incoming message have been created and delivered.
*/
public ListenableFuture<Boolean> expectMockedMessageIn(int noOfMessages)
{
ResultsCompletionFuture<MessageIn<?>> ret = new ResultsCompletionFuture<>(noOfMessages, deliveredResponses);
executor.execute(ret);
return ret;
}
/**
* Returns a future with the first intercepted outbound message that would have been send.
*/
public ListenableFuture<MessageOut<?>> captureMessageOut()
{
return Futures.transform(captureMessageOut(1), (List<MessageOut<?>> result) -> result.isEmpty() ? null : result.get(0));
}
/**
* Returns a future with the specified number of intercepted outbound messages that would have been send.
*/
public ListenableFuture<List<MessageOut<?>>> captureMessageOut(int noOfMessages)
{
CapturedResultsFuture<MessageOut<?>> ret = new CapturedResultsFuture<>(noOfMessages, interceptedMessages);
executor.execute(ret);
return ret;
}
/**
* Returns a future that will indicate if an intercepted outbound messages would have been send.
*/
public ListenableFuture<Boolean> interceptMessageOut()
{
return interceptMessageOut(1);
}
/**
* Returns a future that will indicate if the specified number of intercepted outbound messages would have been send.
*/
public ListenableFuture<Boolean> interceptMessageOut(int noOfMessages)
{
ResultsCompletionFuture<MessageOut<?>> ret = new ResultsCompletionFuture<>(noOfMessages, interceptedMessages);
executor.execute(ret);
return ret;
}
/**
* Returns a future that will indicate the absence of any intercepted outbound messages with the specifed period.
*/
public ListenableFuture<Boolean> interceptNoMsg(long time, TimeUnit unit)
{
ResultAbsenceFuture<MessageOut<?>> ret = new ResultAbsenceFuture<>(interceptedMessages, time, unit);
executor.execute(ret);
return ret;
}
void matchingMessage(MessageOut<?> message)
{
messagesIntercepted++;
logger.trace("Received matching message: {}", message);
interceptedMessages.add(message);
}
void matchingResponse(MessageIn<?> response)
{
mockedMessageResponses++;
logger.trace("Responding to intercepted message: {}", response);
deliveredResponses.add(response);
}
private static class CapturedResultsFuture<T> extends AbstractFuture<List<T>> implements Runnable
{
private final int waitForResults;
private final List<T> results;
private final BlockingQueue<T> queue;
CapturedResultsFuture(int waitForResponses, BlockingQueue<T> queue)
{
this.waitForResults = waitForResponses;
results = new ArrayList<T>(waitForResponses);
this.queue = queue;
}
public void run()
{
try
{
while (results.size() < waitForResults)
results.add(queue.take());
set(results);
}
catch (InterruptedException e)
{
throw new AssertionError();
}
}
}
private static class ResultsCompletionFuture<T> extends AbstractFuture<Boolean> implements Runnable
{
private final int waitForResults;
private final BlockingQueue<T> queue;
ResultsCompletionFuture(int waitForResponses, BlockingQueue<T> queue)
{
this.waitForResults = waitForResponses;
this.queue = queue;
}
public void run()
{
try
{
for (int i = 0; i < waitForResults; i++)
{
queue.take();
}
set(true);
}
catch (InterruptedException e)
{
throw new AssertionError();
}
}
}
private static class ResultAbsenceFuture<T> extends AbstractFuture<Boolean> implements Runnable
{
private final BlockingQueue<T> queue;
private final long time;
private final TimeUnit unit;
ResultAbsenceFuture(BlockingQueue<T> queue, long time, TimeUnit unit)
{
this.queue = queue;
this.time = time;
this.unit = unit;
}
public void run()
{
try
{
T result = queue.poll(time, unit);
if (result != null)
setException(new AssertionFailedError("Received unexpected message: " + result));
else
set(true);
}
catch (InterruptedException e)
{
throw new AssertionError();
}
}
}
}