Examples with LeadershipCoordinator com.palantir.leader.proxy.LeadershipCoordinator used on opensource projects

Example 1 with LeadershipCoordinator

use of com.palantir.leader.proxy.LeadershipCoordinator in project atlasdb by palantir.

the class DefaultLockAndTimestampServiceFactory method createRawLeaderServices.

private static LockAndTimestampServices createRawLeaderServices(MetricsManager metricsManager, LeaderConfig leaderConfig, Consumer<Object> env, Supplier<LockService> lock, Supplier<ManagedTimestampService> time, UserAgent userAgent) {
    // Create local services, that may or may not end up being registered in an Consumer<Object>.
    LocalPaxosServices localPaxosServices = Leaders.createAndRegisterLocalServices(metricsManager, env, leaderConfig, userAgent);
    LeadershipCoordinator leadershipCoordinator = localPaxosServices.leadershipCoordinator();
    LockService localLock = AwaitingLeadershipProxy.newProxyInstance(LockService.class, lock, leadershipCoordinator);
    ManagedTimestampService managedTimestampProxy = AwaitingLeadershipProxy.newProxyInstance(ManagedTimestampService.class, time, leadershipCoordinator);
    // These facades are necessary because of the semantics of the JAX-RS algorithm (in particular, accepting
    // just the managed timestamp service will *not* work).
    TimestampService localTime = getTimestampFacade(managedTimestampProxy);
    TimestampManagementService localManagement = getTimestampManagementFacade(managedTimestampProxy);
    env.accept(localLock);
    env.accept(localTime);
    env.accept(localManagement);
    // Create remote services, that may end up calling our own local services.
    ImmutableServerListConfig serverListConfig = ImmutableServerListConfig.builder().servers(leaderConfig.leaders()).sslConfiguration(leaderConfig.sslConfiguration()).build();
    ServiceCreator creator = ServiceCreator.noPayloadLimiter(metricsManager, Refreshable.only(serverListConfig), userAgent, () -> RemotingClientConfigs.DEFAULT);
    LockService remoteLock = new RemoteLockServiceAdapter(creator.createService(NamespaceAgnosticLockRpcClient.class));
    TimestampService remoteTime = creator.createService(TimestampService.class);
    TimestampManagementService remoteManagement = creator.createService(TimestampManagementService.class);
    if (leaderConfig.leaders().size() == 1) {
        // Attempting to connect to ourself while processing a request can lead to deadlock if incoming request
        // volume is high, as all Jetty threads end up waiting for the timestamp server, and no threads remain to
        // actually handle the timestamp server requests. If we are the only single leader, we can avoid the
        // deadlock entirely; so use PingableLeader's getUUID() to detect this situation and eliminate the redundant
        // call.
        PingableLeader localPingableLeader = localPaxosServices.localPingableLeader();
        String localServerId = localPingableLeader.getUUID();
        PingableLeader remotePingableLeader = AtlasDbHttpClients.createProxy(ServiceCreator.createTrustContext(leaderConfig.sslConfiguration()), Iterables.getOnlyElement(leaderConfig.leaders()), PingableLeader.class, AuxiliaryRemotingParameters.builder().userAgent(userAgent).shouldRetry(true).shouldLimitPayload(true).shouldUseExtendedTimeout(false).build());
        // Determine asynchronously whether the remote services are talking to our local services.
        CompletableFuture<Boolean> useLocalServicesFuture = new CompletableFuture<>();
        TransactionManagers.runAsync.accept(() -> {
            int attemptsLeftBeforeLog = ATTEMPTS_BEFORE_LOGGING_FAILURE_TO_READ_REMOTE_TIMESTAMP_SERVER_ID;
            while (true) {
                try {
                    String remoteServerId = remotePingableLeader.getUUID();
                    useLocalServicesFuture.complete(localServerId.equals(remoteServerId));
                    return;
                } catch (ClientErrorException e) {
                    useLocalServicesFuture.complete(false);
                    return;
                } catch (UnknownRemoteException e) {
                    // manifest as ClientErrorExceptions.
                    if (400 <= e.getStatus() && e.getStatus() <= 499) {
                        useLocalServicesFuture.complete(false);
                        return;
                    }
                    attemptsLeftBeforeLog = logFailureToReadRemoteTimestampServerId(attemptsLeftBeforeLog, e);
                } catch (Throwable e) {
                    attemptsLeftBeforeLog = logFailureToReadRemoteTimestampServerId(attemptsLeftBeforeLog, e);
                }
                Uninterruptibles.sleepUninterruptibly(Duration.ofSeconds(1));
            }
        });
        // Create dynamic service proxies, that switch to talking directly to our local services if it turns out our
        // remote services are pointed at them anyway.
        LockService dynamicLockService = LocalOrRemoteProxy.newProxyInstance(LockService.class, localLock, remoteLock, useLocalServicesFuture);
        // Use managedTimestampProxy here to avoid local calls going through indirection.
        TimestampService dynamicTimeService = LocalOrRemoteProxy.newProxyInstance(TimestampService.class, managedTimestampProxy, remoteTime, useLocalServicesFuture);
        TimestampManagementService dynamicManagementService = LocalOrRemoteProxy.newProxyInstance(TimestampManagementService.class, managedTimestampProxy, remoteManagement, useLocalServicesFuture);
        return ImmutableLockAndTimestampServices.builder().lock(dynamicLockService).timestamp(dynamicTimeService).timestampManagement(dynamicManagementService).timelock(new LegacyTimelockService(dynamicTimeService, dynamicLockService, TransactionManagers.LOCK_CLIENT)).build();
    } else {
        return ImmutableLockAndTimestampServices.builder().lock(remoteLock).timestamp(remoteTime).timestampManagement(remoteManagement).timelock(new LegacyTimelockService(remoteTime, remoteLock, TransactionManagers.LOCK_CLIENT)).build();
    }
}

Example 2 with LeadershipCoordinator

use of com.palantir.leader.proxy.LeadershipCoordinator in project atlasdb by palantir.

the class Leaders method createInstrumentedLocalServices.

public static LocalPaxosServices createInstrumentedLocalServices(MetricsManager metricsManager, LeaderConfig config, RemotePaxosServerSpec remotePaxosServerSpec, Supplier<RemotingClientConfig> remotingClientConfig, UserAgent userAgent, LeadershipObserver leadershipObserver) {
    UUID leaderUuid = UUID.randomUUID();
    PaxosLeadershipEventRecorder leadershipEventRecorder = PaxosLeadershipEventRecorder.create(metricsManager.getTaggedRegistry(), leaderUuid.toString(), leadershipObserver, ImmutableList.of());
    PaxosAcceptor ourAcceptor = AtlasDbMetrics.instrumentTimed(metricsManager.getRegistry(), PaxosAcceptor.class, PaxosAcceptorImpl.newAcceptor(config.acceptorLogDir().getPath()));
    PaxosLearner ourLearner = AtlasDbMetrics.instrumentTimed(metricsManager.getRegistry(), PaxosLearner.class, PaxosLearnerImpl.newLearner(config.learnerLogDir().getPath(), leadershipEventRecorder));
    Optional<TrustContext> trustContext = ServiceCreator.createTrustContext(config.sslConfiguration());
    List<PaxosLearner> learners = createProxyAndLocalList(ourLearner, remotePaxosServerSpec.remoteLearnerUris(), remotingClientConfig, trustContext, PaxosLearner.class, userAgent);
    List<PaxosLearner> remoteLearners = learners.stream().filter(learner -> !learner.equals(ourLearner)).collect(ImmutableList.toImmutableList());
    PaxosLearnerNetworkClient learnerNetworkClient = SingleLeaderLearnerNetworkClient.createLegacy(ourLearner, remoteLearners, config.quorumSize(), createExecutorsForService(metricsManager, learners, "knowledge-update"), PaxosConstants.CANCEL_REMAINING_CALLS);
    List<PaxosAcceptor> acceptors = createProxyAndLocalList(ourAcceptor, remotePaxosServerSpec.remoteAcceptorUris(), remotingClientConfig, trustContext, PaxosAcceptor.class, userAgent);
    PaxosAcceptorNetworkClient acceptorNetworkClient = SingleLeaderAcceptorNetworkClient.createLegacy(acceptors, config.quorumSize(), createExecutorsForService(metricsManager, acceptors, "latest-round-verifier"), PaxosConstants.CANCEL_REMAINING_CALLS);
    List<LeaderPingerContext<PingableLeader>> otherLeaders = generatePingables(remotePaxosServerSpec.remoteLeaderUris(), remotingClientConfig, trustContext, userAgent);
    LeaderPinger leaderPinger = SingleLeaderPinger.createLegacy(createExecutorsForService(metricsManager, otherLeaders, "leader-ping"), config.leaderPingResponseWait(), leaderUuid, PaxosConstants.CANCEL_REMAINING_CALLS);
    LeaderElectionService uninstrumentedLeaderElectionService = new LeaderElectionServiceBuilder().leaderUuid(leaderUuid).knowledge(ourLearner).eventRecorder(leadershipEventRecorder).randomWaitBeforeProposingLeadership(config.randomWaitBeforeProposingLeadership()).pingRate(config.pingRate()).leaderPinger(leaderPinger).acceptorClient(acceptorNetworkClient).learnerClient(learnerNetworkClient).decorateProposer(proposer -> AtlasDbMetrics.instrumentTimed(metricsManager.getRegistry(), PaxosProposer.class, proposer)).leaderAddressCacheTtl(config.leaderAddressCacheTtl()).build();
    LeaderElectionService leaderElectionService = AtlasDbMetrics.instrumentTimed(metricsManager.getRegistry(), LeaderElectionService.class, uninstrumentedLeaderElectionService);
    PingableLeader pingableLeader = AtlasDbMetrics.instrumentTimed(metricsManager.getRegistry(), PingableLeader.class, new LocalPingableLeader(ourLearner, leaderUuid));
    List<PingableLeader> remotePingableLeaders = otherLeaders.stream().map(LeaderPingerContext::pinger).collect(Collectors.toList());
    BatchingLeaderElectionService batchingLeaderElectionService = new BatchingLeaderElectionService(leaderElectionService);
    return ImmutableLocalPaxosServices.builder().ourAcceptor(ourAcceptor).ourLearner(ourLearner).leaderElectionService(batchingLeaderElectionService).leadershipCoordinator(LeadershipCoordinator.create(batchingLeaderElectionService)).localPingableLeader(pingableLeader).remotePingableLeaders(remotePingableLeaders).build();
}

Example 3 with LeadershipCoordinator

use of com.palantir.leader.proxy.LeadershipCoordinator in project atlasdb by palantir.

the class LeadershipContextFactory method create.

@Override
public LeadershipContext create(Client client) {
    ClientAwareComponents clientAwareComponents = ImmutableClientAwareComponents.builder().from(this).proxyClient(client).build();
    BatchingLeaderElectionService leaderElectionService = leaderElectionServiceFactory().create(clientAwareComponents);
    LeadershipCoordinator leadershipCoordinator = leadershipCoordinatorFactory().create(leaderElectionService);
    return ImmutableLeadershipContext.builder().leadershipMetrics(clientAwareComponents.leadershipMetrics()).leaderElectionService(leaderElectionService).addCloseables(leaderElectionService).leadershipCoordinator(leadershipCoordinator).addCloseables(leadershipCoordinatorFactory()).addAllCloseables(leaderPingerFactory().closeables()).build();
}