/**
* Copyright 2008 Google Inc.
*
* Licensed 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.waveprotocol.wave.concurrencycontrol.channel;
import junit.framework.TestCase;
import org.waveprotocol.wave.common.logging.PrintLogger;
import org.waveprotocol.wave.common.logging.AbstractLogger.Level;
import org.waveprotocol.wave.concurrencycontrol.client.ConcurrencyControl;
import org.waveprotocol.wave.concurrencycontrol.common.ChannelException;
import org.waveprotocol.wave.concurrencycontrol.common.ResponseCode;
import org.waveprotocol.wave.model.operation.wave.TransformedWaveletDelta;
import org.waveprotocol.wave.model.operation.wave.WaveletDelta;
import org.waveprotocol.wave.model.operation.wave.WaveletOperation;
import org.waveprotocol.wave.model.operation.wave.WaveletOperationContext;
import org.waveprotocol.wave.model.testing.DeltaTestUtil;
import org.waveprotocol.wave.model.version.HashedVersion;
import org.waveprotocol.wave.model.wave.ParticipantId;
import java.util.List;
/**
* Tests OperationChannelImpl by mocking the underlying WaveletDeltaChannel.
*
* TODO(anorth): this is really tests for the channel+CC combination. Create
* some simpler tests with a fake CC too.
*
*/
public class OperationChannelImplTest extends TestCase {
///////////////////// PRIVATES //////////////////////
private static final ParticipantId USER_ID = ParticipantId.ofUnsafe("test@example.com");
private static final DeltaTestUtil UTIL = new DeltaTestUtil(USER_ID);
private static final byte[] SIG1 = new byte[] { 1, 1, 1, 1 };
private static final byte[] SIG2 = new byte[] { 2, 2, 2, 2 };
private static final byte[] SIG3 = new byte[] { 3, 3, 3, 3 };
private static final byte[] SIG4 = new byte[] { 4, 4, 4, 4 };
private static final byte[] SIG5 = new byte[] { 5, 5, 5, 5 };
private MockWaveletDeltaChannel deltaChannel;
private ConcurrencyControl cc;
private OperationChannelImpl operationChannel;
private final MockOperationChannelListener listener = new MockOperationChannelListener();
///////////////////// SETUP //////////////////////
private static PrintLogger opLogger = new PrintLogger();
private static PrintLogger ccLogger = new PrintLogger();
static {
// We should not be logging fatals in CC.
opLogger.setAllowedMinLogLevel(Level.ERROR);
ccLogger.setAllowedMinLogLevel(Level.ERROR);
}
@Override
public void tearDown() {
listener.clear();
}
///////////////////// UTILITY METHODS FOR TESTS //////////////////////
/**
* Returns a Delta with the requested number of ops, version number
* and signature.
*/
private TransformedWaveletDelta createRandomTransformedDelta(int targetVersion, int opCount,
byte[] hash) {
return UTIL.makeTransformedDelta(0L, HashedVersion.of(targetVersion + opCount, hash), opCount);
}
/**
* Connects the channel at the provided version.
*/
private void connectChannel(long version, byte[] signature) throws ChannelException {
final HashedVersion signatureInfo = HashedVersion.of(version, signature);
deltaChannel = new MockWaveletDeltaChannel();
cc = new ConcurrencyControl(ccLogger, signatureInfo);
operationChannel = new OperationChannelImpl(opLogger, deltaChannel, cc,
Accessibility.READ_WRITE);
operationChannel.setListener(listener);
operationChannel.onConnection(signatureInfo, signatureInfo);
}
/**
* Reconnects the channel at the provided version, which is also
* the current version.
*/
private void reconnectChannel(long connectVersion, byte[] connectSignature)
throws ChannelException {
reconnectChannel(connectVersion, connectSignature, connectVersion, connectSignature, null);
}
/**
* Fails and reconnects the channel at the provided connection version and
* current version. The channel is expected to provide a distinct version
* matching the connect version. If expectRetransmission is not null expects
* the channel to attempt to send that message on reconnection.
*/
private void reconnectChannel(long connectVersion, byte[] connectSignature,
long currentVersion, byte[] currentSignature, WaveletDelta expectRetransmission)
throws ChannelException {
final HashedVersion connectHashedVersion = HashedVersion.of(connectVersion, connectSignature);
final HashedVersion currentHashedVersion = HashedVersion.of(currentVersion, currentSignature);
// Simulate failure elsewhere.
operationChannel.reset();
// Check reconnect versions provided by the channel include the
// version we'll reconnect at.
List<HashedVersion> reconnectVersions = operationChannel.getReconnectVersions();
assertTrue(reconnectVersions.size() > 0);
boolean matchedSignature = false;
for (HashedVersion rcv : reconnectVersions) {
if (connectVersion == rcv.getVersion() && connectSignature.equals(rcv.getHistoryHash())) {
matchedSignature = true;
}
}
assertTrue("No matching signature provided", matchedSignature);
// Simulate reconnection reconnection message from delta channel.
if (expectRetransmission != null) {
deltaChannel.expectSend(expectRetransmission);
}
operationChannel.onConnection(connectHashedVersion, currentHashedVersion);
}
private WaveletDelta sendAndCheckRandomOp(OperationChannelImpl opChannel,
long currentVersion, byte[] signature) throws ChannelException {
WaveletDelta delta = UTIL.makeDelta(HashedVersion.of(currentVersion, signature), 0L, 1);
deltaChannel.expectSend(delta);
opChannel.send(new WaveletOperation[] {delta.get(0)});
return delta;
}
private void checkExpectationsSatisfied() {
deltaChannel.checkExpectationsSatisfied();
}
///////////////////// TESTS //////////////////////
/**
* Test a simple connect.
*/
public void testConnectSuccess() throws ChannelException {
connectChannel(10, SIG1);
listener.checkOpsReceived(0);
checkExpectationsSatisfied();
}
/**
* Test a simple connect then successful disconnection.
*/
public void testConnectThenDisconnectSuccess() throws ChannelException {
connectChannel(10, SIG1);
listener.checkOpsReceived(0);
// Disconnect
operationChannel.reset();
checkExpectationsSatisfied();
}
/**
* Test simple reconnect.
*/
public void testSimpleReconnect() throws ChannelException {
connectChannel(10, SIG1);
listener.checkOpsReceived(0);
// Now disconnect server-side, forcing a reconnect.
reconnectChannel(10, SIG1);
// No new messages.
listener.checkOpsReceived(0);
checkExpectationsSatisfied();
}
/**
* Test receiving a simple delta that was committed.
*/
public void testSimpleReceive() throws ChannelException {
final int initialVersion = 42;
connectChannel(initialVersion, SIG1);
operationChannel.onDelta(createRandomTransformedDelta(initialVersion, 1, SIG2));
listener.checkOpsReceived(1);
listener.clear();
assertNotNull(operationChannel.receive());
listener.checkOpsReceived(0);
// TODO(anorth): test OnCommit by mocking CC
operationChannel.onCommit(initialVersion + 1);
checkExpectationsSatisfied();
}
public void testSimpleSendAndAck() throws Exception {
final int initialVersion = 42;
connectChannel(initialVersion, SIG1);
sendAndCheckRandomOp(operationChannel, initialVersion, SIG1);
listener.clear();
HashedVersion signature = HashedVersion.of(43, SIG2);
operationChannel.onAck(1, signature);
// Listener should receive a version update op.
listener.checkOpsReceived(1);
WaveletOperation op = operationChannel.receive();
WaveletOperationContext context = op.getContext();
assertEquals(1, context.getVersionIncrement());
assertEquals(signature, context.getHashedVersion());
}
/**
* Test simple NACK and onDelta.
* Nack is not supposed to happen, so it should be death.
*/
public void testSimpleNackAndReceive() throws Exception {
final int initialVersion = 42;
connectChannel(initialVersion, SIG1);
sendAndCheckRandomOp(operationChannel, initialVersion, SIG1);
listener.clear();
try {
operationChannel.onNack(ResponseCode.OK, null, 43);
fail("Should have thrown ChannelException");
} catch (ChannelException expected) {
}
checkExpectationsSatisfied();
}
public void testSendToInaccessibleChanneFails() throws ChannelException {
final HashedVersion connectSig = HashedVersion.unsigned(0);
deltaChannel = new MockWaveletDeltaChannel();
cc = new ConcurrencyControl(ccLogger, connectSig);
operationChannel = new OperationChannelImpl(opLogger, deltaChannel, cc,
Accessibility.READ_ONLY);
operationChannel.setListener(listener);
operationChannel.onConnection(connectSig, connectSig);
try {
sendAndCheckRandomOp(operationChannel, connectSig.getVersion(), connectSig.getHistoryHash());
fail("Expected a channel exception");
} catch (ChannelException expected) {
}
}
public void testReconnectAfterCommit() throws Exception {
final int initialVersion = 42;
connectChannel(initialVersion, SIG1);
sendAndCheckRandomOp(operationChannel, 42, SIG1);
operationChannel.onAck(1, HashedVersion.of(43, SIG2));
// Take the fake op resulting from ack that updates version info.
listener.checkOpsReceived(1);
assertNotNull(operationChannel.receive());
listener.clear();
operationChannel.onCommit(43); // Causes cc to remove old operations from memory
reconnectChannel(43, SIG2);
// Receive next delta.
TransformedWaveletDelta delta = createRandomTransformedDelta(43, 1, SIG3);
operationChannel.onDelta(delta);
listener.checkOpsReceived(1);
assertNotNull(operationChannel.receive());
assertNull(operationChannel.receive());
checkExpectationsSatisfied();
}
/**
* Test reconnect where there was an unACKed delta during the failure which
* was not received by the server, expect the client to immediately resend the
* delta.
*/
public void testReconnectWithPendingAckNotRecievedByServer() throws Exception {
final int initialVersion = 42;
final byte[] ackSignature = SIG2;
connectChannel(initialVersion, SIG1);
WaveletDelta delta = sendAndCheckRandomOp(operationChannel, 42, SIG1);
// The server's version is still 42 when it responds. Expect a retransmission.
reconnectChannel(initialVersion, SIG1, initialVersion, SIG1, delta);
// Now ack.
listener.checkOpsReceived(0);
operationChannel.onAck(1, HashedVersion.of(43, ackSignature));
// There should be a fake op resulting from ack that updates version info
listener.checkOpsReceived(1);
checkExpectationsSatisfied();
}
/**
* Test reconnect where there was an unACKed delta during the failure which
* was received and ACKed by the server, but this was unseen by the client. On
* reconnect, the server responds with that delta and a new one, the client
* should receive only the new one.
*/
public void testReconnectWithPendingAckAndNewDeltaSentByServer() throws Exception {
final int initialVersion = 42;
final byte[] initialSignature = SIG1;
connectChannel(initialVersion, initialSignature);
WaveletDelta delta = sendAndCheckRandomOp(operationChannel, 42, SIG1);
// Reconnect at the version before that delta, but with a later
// current version including it.
final long afterVersion = 44;
final byte[] afterSignature = SIG3;
reconnectChannel(initialVersion, initialSignature, afterVersion, afterSignature, null);
// Receive delta that is the client's own un-acked op.
TransformedWaveletDelta serverDelta =
TransformedWaveletDelta.cloneOperations(HashedVersion.of(43, SIG2), 0L, delta);
operationChannel.onDelta(serverDelta);
// It should implicitly cause an ack, so read that fake op
// to update version info, plus a VersionUpdateOp.
listener.checkOpsReceived(2);
assertNotNull(operationChannel.receive());
listener.clear();
// Receive another op
TransformedWaveletDelta rdelta = createRandomTransformedDelta(43, 1, SIG4);
operationChannel.onDelta(rdelta);
// Recovery should be complete since the client has caught up with the
// server, and there should be one readable delta.
listener.checkOpsReceived(1);
assertNotNull(operationChannel.receive());
checkExpectationsSatisfied();
}
/**
* Test reconnect where there was an ACKed and an unACKed delta, the server
* loses state and accepted a delta from another client assigning the same
* version number. Expect failure.
*/
public void testReconnectFailureWithAckAndPendingAckWithCollidingVersionNumber()
throws Exception {
final int initialVersion = 42;
final byte[] initialSignature = SIG1;
final byte[] ackSignature = SIG2;
connectChannel(initialVersion, initialSignature);
// Send an op and ack it.
sendAndCheckRandomOp(operationChannel, 42, SIG1);
operationChannel.onAck(1, HashedVersion.of(43, ackSignature));
// Take the fake op resulting from ack that updates version info.
listener.checkOpsReceived(1);
assertNotNull(operationChannel.receive());
listener.clear();
// Send an op, then fail & reconnect.
// Note(anorth): this makes no sense. Why would the server reconnect
// at 43 with the same acked signature if it lost state.
sendAndCheckRandomOp(operationChannel, 43, ackSignature);
reconnectChannel(43, ackSignature, 47, SIG3, null);
// Receive a different delta to the first one the client sent.
try {
operationChannel.onDelta(createRandomTransformedDelta(42, 5, SIG4));
fail("Should have thrown ChannelException");
} catch (ChannelException expected) {
}
checkExpectationsSatisfied();
}
/**
* Tests reconnection where the server does not provide a matching
* signature. Expect failure.
*/
public void testReconnectionFailure() throws ChannelException {
final int initialVersion = 42;
final byte[] initialSignature = SIG1;
connectChannel(initialVersion, initialSignature);
// Simulate failure
operationChannel.reset();
// Server presents unknown reconnect version
final HashedVersion reconnectVersion = HashedVersion.of(66, SIG2);
try {
operationChannel.onConnection(reconnectVersion, reconnectVersion);
fail("Should have thrown ChannelException");
} catch (ChannelException expected) {
}
}
/**
* Test reconnect where client sends a delta to the server and the server
* forgets that delta on reconnection. Then check life can continue as normal
* after reconnection.
*/
public void testReconnectWherePendingAckCollisionCanBeRecovered() throws Exception {
final int initialVersion = 42;
final byte[] initialSignature = SIG1;
connectChannel(initialVersion, initialSignature);
// Receive a delta to resets the recovery mechanism so the next
// recovery will be at version 43.
final byte[] signature43 = SIG2;
operationChannel.onDelta(createRandomTransformedDelta(42, 1, signature43));
assertNotNull(operationChannel.receive());
listener.clear();
// Send a delta.
sendAndCheckRandomOp(operationChannel, 43, signature43);
// Reconnect at 43.
reconnectChannel(43, signature43, 44, SIG3, null);
// Now receive a different delta to the un-acked delta1.
TransformedWaveletDelta delta2 = createRandomTransformedDelta(43, 1, SIG4);
operationChannel.onDelta(delta2);
listener.checkOpsReceived(1);
assertNotNull(operationChannel.receive());
listener.clear();
// Push another delta to the channel, but don't expect a delta channel
// send yet.
WaveletDelta delta3 = UTIL.makeDelta(HashedVersion.of(45, SIG5), 0L, 1);
operationChannel.send(new WaveletOperation[] { delta3.get(0) });
listener.checkOpsReceived(0);
// Ack the first op, and expect a send for the pending op3.
deltaChannel.expectSend(delta3);
operationChannel.onAck(1, HashedVersion.of(45, SIG5));
checkExpectationsSatisfied();
}
/**
* Check that the client sends the correct last known signatures.
*/
public void testReconnectWhereAnAckWasNotCommittedCanBeRecovered() throws Exception {
final int initialVersion = 42;
connectChannel(initialVersion, SIG1);
// Send op and expect an Ack.
byte[] signature43 = SIG2;
byte[] signature44 = SIG3;
sendAndCheckRandomOp(operationChannel, 42, SIG1);
operationChannel.onAck(1, HashedVersion.of(43, signature43));
// Send another op and expect an Ack.
WaveletDelta delta2 = sendAndCheckRandomOp(operationChannel, 43, signature43);
operationChannel.onAck(1, HashedVersion.of(44, signature44));
// send commit for first Ack.
operationChannel.onCommit(43);
// Check that we reconnect, the server went down and has a LCV of 43.
// Channel will resend delta2.
reconnectChannel(43, signature43, 43, signature43, delta2);
deltaChannel.checkExpectationsSatisfied();
checkExpectationsSatisfied();
}
// TODO(zdwang): The test below is too complicated to read now. My head hurts. Fix later, or remove
// as thorough test of recovery is already done in OT3Test
//
// private class Pair<A, B> {
// A first;
// B second;
// Pair (A first, B second) {
// this.first = first;
// this.second = second;
// }
// }
//
// /**
// * Method used by tests for recovery where we have sent a number of deltas
// * all of which have been ACKed, then reconnect.
// * We expect retransmission of all those deltas that the server has
// * received/not forgotten, the client retransmits the rest.
// *
// * @param initialServerVersion version the server starts on.
// * @param ackedClientOps number of deltas sent by client & ACKed by server.
// * @param numberOfDeltasRememberedByServer number of deltas that the server remembers
// after crash.
// * @param disconnectDuringStartup forces client to disconnect during recovery when in start up.
// * @param disconnectWhileRetransmitting forces client to disconnect while retransmitting
// * previously ACKed deltas.
// * @param mergeStartupDeltas allows the server may merge adjacent deltas.
// * @param useCommitDuringStartup makes the server indicate a commit during the startup.
// * @param useCommitWhileRetransmitting makes the server indicate a commit while retransmitting
// * previously ACKed deltas.
// */
// private void reconnectWithRetransmissionOfPreviouslyAckedDeltas(
// int initialServerVersion,
// int ackedClientOps,
// int numberOfDeltasRememberedByServer,
// boolean disconnectDuringStartup,
// boolean disconnectWhileRetransmitting,
// boolean mergeStartupDeltas,
// boolean useCommitDuringStartup,
// boolean useCommitWhileRetransmitting) {
//
// assert numberOfDeltasRememberedByServer >= 0 &&
// numberOfDeltasRememberedByServer <= ackedClientOps;
//
// int reconnectVersion = initialServerVersion;
// int reconnectSignature = randomInt();
// WaveletDeltaChannel.Receiver oldReceiver = utilCheckAndCompleteConnect(
// operationChannel.getDeltaChannel(), sig(reconnectVersion, reconnectSignature));
// int version = reconnectVersion;
// // Store each op together with a signature value.
// ArrayList<Pair<WaveOpMessage, Integer>> savedInitialOps =
// new ArrayList<Pair<WaveOpMessage, Integer>>();
// for (int i = 0; i < ackedClientOps; i++) {
// int signature = randomInt();
// // TODO(jochen): once we have better control over how ops are collated into deltas, do more
// // than one op per delta.
// savedInitialOps.add(new Pair<WaveOpMessage, Integer>(
// utilSendAndCheckRndOp(operationChannel, version), signature));
//
// version += 1; // Update to be the version AFTER the sent delta is applied.
// oldReceiver.onAck(1, sig(version, signature));
// }
// if (numberOfDeltasRememberedByServer > 0) {
// reconnectSignature = savedInitialOps.get(numberOfDeltasRememberedByServer - 1).second;
// }
//
// int postStartUpServerVersion = initialServerVersion + numberOfDeltasRememberedByServer;
// int finalServerVersion = initialServerVersion + ackedClientOps;
// do {
// // Make a local copy used for retransmission.
// ArrayList<Pair<WaveOpMessage, Integer>> initialOps =
// new ArrayList<Pair<WaveOpMessage, Integer>>(savedInitialOps);
//
// listener.clear();
// callback.clear();
// // The server may have remembered some deltas.
// WaveletDeltaChannel.Receiver receiver = utilDisconnectReconnect(oldReceiver,
// sig(reconnectVersion, reconnectSignature),
// sig(postStartUpServerVersion, reconnectSignature));
//
// MockWaveletDeltaChannel deltaChannel = operationChannel.getDeltaChannel();
//
// // The server sends the deltas it remembered, optionally merging them.
// for (int receiveVersion = reconnectVersion; receiveVersion < postStartUpServerVersion;) {
// int signature = -1;
// ArrayList<WaveOpMessage> ops = new ArrayList<WaveOpMessage>();
// for (int i = 0; i < (mergeStartupDeltas ? 2 : 1) && receiveVersion + ops.size() <
// postStartUpServerVersion; ++i) {
// Pair<WaveOpMessage, Integer> opSignaturePair = initialOps.remove(0);
// ops.add(opSignaturePair.first);
// signature = opSignaturePair.second; // Always use the last signature.
// }
// assert ops.size() > 0;
// WaveDeltaMessage delta = utilCreateDeltaMessage(receiveVersion, signature, 0L, ops);
// receiver.onDelta(delta);
//
// callback.assertCounts(0, 0);
// assertNull(operationChannel.receive());
// receiveVersion += delta.getOpListSize();
//
// if (useCommitDuringStartup) {
// reconnectVersion = receiveVersion;
// reconnectSignature = signature;
// receiver.onCommit(reconnectVersion);
// for (int i = 0; i < delta.getOpListSize(); i++) {
// savedInitialOps.remove(0); // On reconnect, the ops so far will not be sent.
// }
// }
//
// if (disconnectDuringStartup) {
// continue; // break out of loop
// }
// }
// if (disconnectDuringStartup) {
// disconnectDuringStartup = false;
// // Check to make sure that if we break out at startup, that we still check there
// // was a send
// // if we expected one.
// if (postStartUpServerVersion < finalServerVersion) {
// deltaChannel.checkSend();
// }
// continue; // back to top.
// }
//
// // The client retransmits the remainder, so ACK each one.
// for (int rexmitVersion = postStartUpServerVersion; rexmitVersion < finalServerVersion;
// ++rexmitVersion) {
// utilCheckOpsSent(operationChannel, rexmitVersion, initialOps.get(0).first);
//
// receiver.onAck(1, sig(rexmitVersion + 1, randomInt())); // ACK the op.
// if (useCommitWhileRetransmitting) {
// reconnectVersion = rexmitVersion + 1;
// receiver.onCommit(reconnectVersion);
// reconnectSignature = initialOps.get(0).second;
// savedInitialOps.remove(0); // When we try to reconnect,
// // the ops so far will not be sent.
// }
// initialOps.remove(0);
//
// if (disconnectWhileRetransmitting) {
// continue; // break out of loop
// }
// }
// deltaChannel.allChecked();
// if (disconnectWhileRetransmitting) {
// disconnectWhileRetransmitting = false;
// continue; // back to top.
// }
// // The condition below is a dummy, both should be false by the time we get here. It saves
// // me from using break here.
// } while(disconnectWhileRetransmitting || disconnectDuringStartup);
// operationChannel.getDeltaChannel().allChecked();
// }
//
//
// // Work around the test harness problem of timing out a test running too long. The hack is to
// // test the last boolean variant in a separate test to prevent the test thread
// // from timing out :(
// // Any other suggestions for fixing this ?
// /**
// * Drive variants of the reconnect and retransmission test.
// */
// public void reconnectWithRetranmissionOfPreviouslyAckedDeltasWithVariations(boolean lastBool) {
// final int maxNumberRemembered = 8;
// // Test the range of numberRemembered deltas by the server against the disconnect
// // combinations.
// for (int boolVariants = 0; boolVariants < 16; boolVariants++) {
// for (int numberRemembered = 0; numberRemembered <= maxNumberRemembered; numberRemembered +=
// 4) {
// reconnectWithRetransmissionOfPreviouslyAckedDeltas(40,
// maxNumberRemembered, numberRemembered, (boolVariants & 1) > 0,
// (boolVariants & 2) > 0, (boolVariants & 4) > 0,
// (boolVariants & 8) > 0, lastBool);
// tearDown();
// setUp();
// }
// }
// // Check the spurious connect we did in the trailing setUp()
// operationChannel.getDeltaChannel().checkConnect();
// }
//
// /**
// * Force GWT to run these as two separate tests.
// */
// public void testReconnectWithRetranmissionOfPreviouslyAckedDeltasA() {
// reconnectWithRetranmissionOfPreviouslyAckedDeltasWithVariations(false);
// }
//
// public void testReconnectWithRetranmissionOfPreviouslyAckedDeltasB() {
// reconnectWithRetranmissionOfPreviouslyAckedDeltasWithVariations(true);
// }
}