/**
* Copyright (C) 2015 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/platform/basic.h"
#include "mongo/db/repl/replication_executor.h"
#include "mongo/db/repl/scatter_gather_algorithm.h"
#include "mongo/db/repl/scatter_gather_runner.h"
#include "mongo/executor/network_interface_mock.h"
#include "mongo/stdx/functional.h"
#include "mongo/stdx/memory.h"
#include "mongo/stdx/thread.h"
#include "mongo/unittest/unittest.h"
namespace mongo {
namespace repl {
namespace {
using executor::NetworkInterfaceMock;
using executor::RemoteCommandRequest;
using executor::RemoteCommandResponse;
static const int kTotalRequests = 3;
/**
* Algorithm for testing the ScatterGatherRunner, which will finish running when finish() is
* called, or upon receiving responses from two nodes. Creates a three requests algorithm
* simulating running an algorithm against three other nodes.
*/
class ScatterGatherTestAlgorithm : public ScatterGatherAlgorithm {
public:
ScatterGatherTestAlgorithm(int64_t maxResponses = 2)
: _done(false), _numResponses(0), _maxResponses(maxResponses) {}
virtual std::vector getRequests() const {
std::vector requests;
for (int i = 0; i < kTotalRequests; i++) {
requests.push_back(RemoteCommandRequest(
HostAndPort("hostname", i), "admin", BSONObj(), nullptr, Milliseconds(30 * 1000)));
}
return requests;
}
virtual void processResponse(const RemoteCommandRequest& request,
const ResponseStatus& response) {
_numResponses++;
}
void finish() {
_done = true;
}
virtual bool hasReceivedSufficientResponses() const {
if (_done) {
return _done;
}
return _numResponses >= _maxResponses;
}
int getResponseCount() {
return _numResponses;
}
private:
bool _done;
int64_t _numResponses;
int64_t _maxResponses;
};
/**
* ScatterGatherTest base class which sets up the ReplicationExecutor and NetworkInterfaceMock.
*/
class ScatterGatherTest : public mongo::unittest::Test {
protected:
NetworkInterfaceMock* getNet() {
return _net;
}
ReplicationExecutor* getExecutor() {
return _executor.get();
}
int64_t countLogLinesContaining(const std::string& needle);
private:
void setUp();
void tearDown();
// owned by _executor
NetworkInterfaceMock* _net;
std::unique_ptr _executor;
std::unique_ptr _executorThread;
};
void ScatterGatherTest::setUp() {
auto net = stdx::make_unique();
_net = net.get();
_executor = stdx::make_unique(std::move(net), 1 /* prng seed */);
_executorThread.reset(new stdx::thread(stdx::bind(&ReplicationExecutor::run, _executor.get())));
}
void ScatterGatherTest::tearDown() {
_executor->shutdown();
_executorThread->join();
}
// Used to run a ScatterGatherRunner in a separate thread, to avoid blocking test execution.
class ScatterGatherRunnerRunner {
public:
ScatterGatherRunnerRunner(ScatterGatherRunner* sgr, ReplicationExecutor* executor)
: _sgr(sgr),
_executor(executor),
_result(Status(ErrorCodes::BadValue, "failed to set status")) {}
// Could block if _sgr has not finished
Status getResult() {
_thread->join();
return _result;
}
void run() {
_thread.reset(
new stdx::thread(stdx::bind(&ScatterGatherRunnerRunner::_run, this, _executor)));
}
private:
void _run(ReplicationExecutor* executor) {
_result = _sgr->run();
}
ScatterGatherRunner* _sgr;
ReplicationExecutor* _executor;
Status _result;
std::unique_ptr _thread;
};
// Simple onCompletion function which will toggle a bool, so that we can check the logs to
// ensure the onCompletion function ran when expected.
executor::TaskExecutor::CallbackFn getOnCompletionTestFunction(bool* ran) {
auto cb = [ran](const ReplicationExecutor::CallbackArgs& cbData) {
if (!cbData.status.isOK()) {
return;
}
*ran = true;
};
return cb;
}
// Confirm that running via start() will finish and run the onComplete function once sufficient
// responses have been received.
// Confirm that deleting both the ScatterGatherTestAlgorithm and ScatterGatherRunner while
// scheduled callbacks still exist will not be unsafe (ASAN builder) after the algorithm has
// completed.
TEST_F(ScatterGatherTest, DeleteAlgorithmAfterItHasCompleted) {
ScatterGatherTestAlgorithm* sga = new ScatterGatherTestAlgorithm();
ScatterGatherRunner* sgr = new ScatterGatherRunner(sga, getExecutor());
bool ranCompletion = false;
StatusWith status = sgr->start();
getExecutor()->onEvent(status.getValue(), getOnCompletionTestFunction(&ranCompletion));
ASSERT_OK(status.getStatus());
ASSERT_FALSE(ranCompletion);
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(2),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(2),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(5),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
net->runUntil(net->now() + Seconds(2));
ASSERT_TRUE(ranCompletion);
delete sga;
delete sgr;
net->runReadyNetworkOperations();
net->exitNetwork();
}
// Confirm that shutting the ReplicationExecutor down before calling run() will cause run()
// to return ErrorCodes::ShutdownInProgress.
TEST_F(ScatterGatherTest, ShutdownExecutorBeforeRun) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
getExecutor()->shutdown();
sga.finish();
Status status = sgr.run();
ASSERT_EQUALS(ErrorCodes::ShutdownInProgress, status);
}
// Confirm that shutting the ReplicationExecutor down after calling run(), but before run()
// finishes will cause run() to return Status::OK().
TEST_F(ScatterGatherTest, ShutdownExecutorAfterRun) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
ScatterGatherRunnerRunner sgrr(&sgr, getExecutor());
sgrr.run();
// need to wait for the scatter-gather to be scheduled in the executor
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
// Black hole all requests before shutdown, so that scheduleRemoteCommand will succeed.
for (int i = 0; i < kTotalRequests; i++) {
NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
net->blackHole(noi);
}
net->exitNetwork();
getExecutor()->shutdown();
Status status = sgrr.getResult();
ASSERT_OK(status);
}
// Confirm that shutting the ReplicationExecutor down before calling start() will cause start()
// to return ErrorCodes::ShutdownInProgress and should not run onCompletion().
TEST_F(ScatterGatherTest, ShutdownExecutorBeforeStart) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
getExecutor()->shutdown();
bool ranCompletion = false;
StatusWith status = sgr.start();
sga.finish();
ASSERT_FALSE(ranCompletion);
ASSERT_EQUALS(ErrorCodes::ShutdownInProgress, status.getStatus());
}
// Confirm that shutting the ReplicationExecutor down after calling start() will cause start()
// to return Status::OK and should not run onCompletion().
TEST_F(ScatterGatherTest, ShutdownExecutorAfterStart) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
bool ranCompletion = false;
StatusWith status = sgr.start();
getExecutor()->onEvent(status.getValue(), getOnCompletionTestFunction(&ranCompletion));
getExecutor()->shutdown();
sga.finish();
ASSERT_FALSE(ranCompletion);
ASSERT_OK(status.getStatus());
}
// Confirm that responses are not processed once sufficient responses have been received.
TEST_F(ScatterGatherTest, DoNotProcessMoreThanSufficientResponses) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
bool ranCompletion = false;
StatusWith status = sgr.start();
getExecutor()->onEvent(status.getValue(), getOnCompletionTestFunction(&ranCompletion));
ASSERT_OK(status.getStatus());
ASSERT_FALSE(ranCompletion);
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(2),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(2),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now() + Seconds(5),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
ASSERT_FALSE(ranCompletion);
net->runUntil(net->now() + Seconds(2));
ASSERT_TRUE(ranCompletion);
net->runReadyNetworkOperations();
// the third resposne should not be processed, so the count should not increment
ASSERT_EQUALS(2, sga.getResponseCount());
net->exitNetwork();
}
// Confirm that starting with sufficient responses received will immediate complete.
TEST_F(ScatterGatherTest, DoNotCreateCallbacksIfHasSufficientResponsesReturnsTrueImmediately) {
ScatterGatherTestAlgorithm sga;
// set hasReceivedSufficientResponses to return true before the run starts
sga.finish();
ScatterGatherRunner sgr(&sga, getExecutor());
bool ranCompletion = false;
StatusWith status = sgr.start();
getExecutor()->onEvent(status.getValue(), getOnCompletionTestFunction(&ranCompletion));
ASSERT_OK(status.getStatus());
// Wait until callback finishes.
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
net->runReadyNetworkOperations();
net->exitNetwork();
ASSERT_TRUE(ranCompletion);
}
#if 0
// TODO Enable this test once we have a way to test for invariants.
// This test ensures we do not process more responses than we've scheduled callbacks for.
TEST_F(ScatterGatherTest, NeverEnoughResponses) {
ScatterGatherTestAlgorithm sga(5);
ScatterGatherRunner sgr(&sga);
bool ranCompletion = false;
StatusWith status = sgr.start(getExecutor(),
getOnCompletionTestFunction(&ranCompletion));
ASSERT_OK(status.getStatus());
ASSERT_FALSE(ranCompletion);
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
net->scheduleResponse(noi,
net->now(),
ResponseStatus(RemoteCommandResponse(
BSON("ok" << 1),
boost::posix_time::milliseconds(10))));
net->runReadyNetworkOperations();
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(noi,
net->now(),
ResponseStatus(RemoteCommandResponse(
BSON("ok" << 1),
boost::posix_time::milliseconds(10))));
net->runReadyNetworkOperations();
ASSERT_FALSE(ranCompletion);
noi = net->getNextReadyRequest();
net->scheduleResponse(noi,
net->now(),
ResponseStatus(RemoteCommandResponse(
BSON("ok" << 1),
boost::posix_time::milliseconds(10))));
net->runReadyNetworkOperations();
net->exitNetwork();
ASSERT_FALSE(ranCompletion);
}
#endif // 0
// Confirm that running via run() will finish once sufficient responses have been received.
TEST_F(ScatterGatherTest, SuccessfulScatterGatherViaRun) {
ScatterGatherTestAlgorithm sga;
ScatterGatherRunner sgr(&sga, getExecutor());
ScatterGatherRunnerRunner sgrr(&sgr, getExecutor());
sgrr.run();
NetworkInterfaceMock* net = getNet();
net->enterNetwork();
NetworkInterfaceMock::NetworkOperationIterator noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now(),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
net->runReadyNetworkOperations();
noi = net->getNextReadyRequest();
net->blackHole(noi);
net->runReadyNetworkOperations();
noi = net->getNextReadyRequest();
net->scheduleResponse(
noi,
net->now(),
ResponseStatus(RemoteCommandResponse(BSON("ok" << 1), BSONObj(), Milliseconds(10))));
net->runReadyNetworkOperations();
net->exitNetwork();
Status status = sgrr.getResult();
ASSERT_OK(status);
}
} // namespace
} // namespace repl
} // namespace mongo