Examples with FsmContext com.digitalpetri.strictmachine.FsmContext used on opensource projects

Example 1 with FsmContext

use of com.digitalpetri.strictmachine.FsmContext in project milo by eclipse.

the class SessionFsmFactory method initialize.

private static CompletableFuture<Unit> initialize(FsmContext<State, Event> ctx, OpcUaClient client, OpcUaSession session) {
    List<SessionFsm.SessionInitializer> initializers = KEY_SESSION_INITIALIZERS.get(ctx).sessionInitializers;
    if (initializers.isEmpty()) {
        return completedFuture(Unit.VALUE);
    } else {
        UaStackClient stackClient = client.getStackClient();
        CompletableFuture<?>[] futures = initializers.stream().map(i -> i.initialize(stackClient, session)).toArray(CompletableFuture[]::new);
        return CompletableFuture.allOf(futures).thenApply(v -> Unit.VALUE);
    }
}

Example 2 with FsmContext

use of com.digitalpetri.strictmachine.FsmContext in project milo by eclipse.

the class SessionFsmFactory method createSession.

@SuppressWarnings("Duplicates")
private static CompletableFuture<CreateSessionResponse> createSession(FsmContext<State, Event> ctx, OpcUaClient client) {
    UaStackClient stackClient = client.getStackClient();
    EndpointDescription endpoint = stackClient.getConfig().getEndpoint();
    String gatewayServerUri = endpoint.getServer().getGatewayServerUri();
    String serverUri;
    if (gatewayServerUri != null && !gatewayServerUri.isEmpty()) {
        serverUri = endpoint.getServer().getApplicationUri();
    } else {
        serverUri = null;
    }
    ByteString clientNonce = NonceUtil.generateNonce(32);
    ByteString clientCertificate = stackClient.getConfig().getCertificate().map(c -> {
        try {
            return ByteString.of(c.getEncoded());
        } catch (CertificateEncodingException e) {
            return ByteString.NULL_VALUE;
        }
    }).orElse(ByteString.NULL_VALUE);
    ApplicationDescription clientDescription = new ApplicationDescription(client.getConfig().getApplicationUri(), client.getConfig().getProductUri(), client.getConfig().getApplicationName(), ApplicationType.Client, null, null, null);
    CreateSessionRequest request = new CreateSessionRequest(client.newRequestHeader(), clientDescription, serverUri, client.getConfig().getEndpoint().getEndpointUrl(), client.getConfig().getSessionName().get(), clientNonce, clientCertificate, client.getConfig().getSessionTimeout().doubleValue(), client.getConfig().getMaxResponseMessageSize());
    LOGGER.debug("[{}] Sending CreateSessionRequest...", ctx.getInstanceId());
    return stackClient.sendRequest(request).thenApply(CreateSessionResponse.class::cast).thenCompose(response -> {
        try {
            SecurityPolicy securityPolicy = SecurityPolicy.fromUri(endpoint.getSecurityPolicyUri());
            if (securityPolicy != SecurityPolicy.None) {
                if (response.getServerCertificate().isNullOrEmpty()) {
                    throw new UaException(StatusCodes.Bad_SecurityChecksFailed, "Certificate missing from CreateSessionResponse");
                }
                List<X509Certificate> serverCertificateChain = CertificateUtil.decodeCertificates(response.getServerCertificate().bytesOrEmpty());
                X509Certificate serverCertificate = serverCertificateChain.get(0);
                X509Certificate certificateFromEndpoint = CertificateUtil.decodeCertificate(endpoint.getServerCertificate().bytesOrEmpty());
                if (!serverCertificate.equals(certificateFromEndpoint)) {
                    throw new UaException(StatusCodes.Bad_SecurityChecksFailed, "Certificate from CreateSessionResponse did not " + "match certificate from EndpointDescription!");
                }
                client.getConfig().getCertificateValidator().validateCertificateChain(serverCertificateChain, endpoint.getServer().getApplicationUri(), EndpointUtil.getHost(endpoint.getEndpointUrl()));
                SignatureData serverSignature = response.getServerSignature();
                byte[] dataBytes = Bytes.concat(clientCertificate.bytesOrEmpty(), clientNonce.bytesOrEmpty());
                byte[] signatureBytes = serverSignature.getSignature().bytesOrEmpty();
                SignatureUtil.verify(SecurityAlgorithm.fromUri(serverSignature.getAlgorithm()), serverCertificate, dataBytes, signatureBytes);
            }
            return completedFuture(response);
        } catch (UaException e) {
            return failedFuture(e);
        }
    });
}

Example 3 with FsmContext

use of com.digitalpetri.strictmachine.FsmContext in project milo by eclipse.

the class SessionFsmFactory method configureActiveState.

private static void configureActiveState(FsmBuilder<State, Event> fb, OpcUaClient client) {
    /* Transitions */
    fb.when(State.Active).on(Event.CloseSession.class).transitionTo(State.Closing);
    fb.when(State.Active).on(e -> e.getClass() == Event.KeepAliveFailure.class || e.getClass() == Event.ServiceFault.class).transitionTo(State.CreatingWait);
    /* External Transition Actions */
    fb.onTransitionTo(State.Active).from(State.Initializing).via(Event.InitializeSuccess.class).execute(ctx -> {
        Event.InitializeSuccess event = (Event.InitializeSuccess) ctx.event();
        // reset the wait time
        KEY_WAIT_TIME.remove(ctx);
        long keepAliveInterval = client.getConfig().getKeepAliveInterval().longValue();
        KEY_KEEP_ALIVE_FAILURE_COUNT.set(ctx, 0L);
        ScheduledFuture<?> scheduledFuture = client.getConfig().getScheduledExecutor().scheduleWithFixedDelay(() -> ctx.fireEvent(new Event.KeepAlive(event.session)), keepAliveInterval, keepAliveInterval, TimeUnit.MILLISECONDS);
        KEY_KEEP_ALIVE_SCHEDULED_FUTURE.set(ctx, scheduledFuture);
        KEY_SESSION.set(ctx, event.session);
        SessionFuture sessionFuture = KEY_SESSION_FUTURE.get(ctx);
        client.getConfig().getExecutor().execute(() -> sessionFuture.future.complete(event.session));
    });
    fb.onTransitionTo(State.Active).from(State.Initializing).via(Event.InitializeSuccess.class).execute(FsmContext::processShelvedEvents);
    fb.onTransitionFrom(State.Active).to(s -> s == State.Closing || s == State.CreatingWait).viaAny().execute(ctx -> {
        ScheduledFuture<?> scheduledFuture = KEY_KEEP_ALIVE_SCHEDULED_FUTURE.remove(ctx);
        if (scheduledFuture != null) {
            scheduledFuture.cancel(false);
        }
    });
    // onSessionActive() callbacks
    fb.onTransitionTo(State.Active).from(s -> s != State.Active).viaAny().execute(ctx -> {
        OpcUaSession session = KEY_SESSION.get(ctx);
        SessionFsm.SessionActivityListeners sessionActivityListeners = KEY_SESSION_ACTIVITY_LISTENERS.get(ctx);
        sessionActivityListeners.sessionActivityListeners.forEach(listener -> listener.onSessionActive(session));
    });
    // onSessionInactive() callbacks
    fb.onTransitionFrom(State.Active).to(s -> s != State.Active).viaAny().execute(ctx -> {
        OpcUaSession session = KEY_SESSION.get(ctx);
        SessionFsm.SessionActivityListeners sessionActivityListeners = KEY_SESSION_ACTIVITY_LISTENERS.get(ctx);
        sessionActivityListeners.sessionActivityListeners.forEach(listener -> listener.onSessionInactive(session));
    });
    /* Internal Transition Actions */
    fb.onInternalTransition(State.Active).via(Event.KeepAlive.class).execute(ctx -> {
        Event.KeepAlive event = (Event.KeepAlive) ctx.event();
        sendKeepAlive(client, event.session).whenComplete((response, ex) -> {
            if (response != null) {
                DataValue[] results = response.getResults();
                if (results != null && results.length > 0) {
                    Object value = results[0].getValue().getValue();
                    if (value instanceof Integer) {
                        ServerState state = ServerState.from((Integer) value);
                        LOGGER.debug("[{}] ServerState: {}", ctx.getInstanceId(), state);
                    }
                }
                KEY_KEEP_ALIVE_FAILURE_COUNT.set(ctx, 0L);
            } else {
                Long keepAliveFailureCount = KEY_KEEP_ALIVE_FAILURE_COUNT.get(ctx);
                if (keepAliveFailureCount == null) {
                    keepAliveFailureCount = 1L;
                } else {
                    keepAliveFailureCount += 1L;
                }
                KEY_KEEP_ALIVE_FAILURE_COUNT.set(ctx, keepAliveFailureCount);
                long keepAliveFailuresAllowed = client.getConfig().getKeepAliveFailuresAllowed().longValue();
                if (keepAliveFailureCount > keepAliveFailuresAllowed) {
                    LOGGER.warn("[{}] Keep Alive failureCount={} exceeds failuresAllowed={}", ctx.getInstanceId(), keepAliveFailureCount, keepAliveFailuresAllowed);
                    ctx.fireEvent(new Event.KeepAliveFailure());
                } else {
                    LOGGER.debug("[{}] Keep Alive failureCount={}", ctx.getInstanceId(), keepAliveFailureCount, ex);
                }
            }
        });
    });
    fb.onInternalTransition(State.Active).via(Event.GetSession.class).execute(SessionFsmFactory::handleGetSessionEvent);
    fb.onInternalTransition(State.Active).via(Event.OpenSession.class).execute(SessionFsmFactory::handleOpenSessionEvent);
}

Example 4 with FsmContext

use of com.digitalpetri.strictmachine.FsmContext in project milo by eclipse.

the class SessionFsmFactory method transferSubscriptions.

@SuppressWarnings("Duplicates")
private static CompletableFuture<Unit> transferSubscriptions(FsmContext<State, Event> ctx, OpcUaClient client, OpcUaSession session) {
    UaStackClient stackClient = client.getStackClient();
    OpcUaSubscriptionManager subscriptionManager = client.getSubscriptionManager();
    ImmutableList<UaSubscription> subscriptions = subscriptionManager.getSubscriptions();
    if (subscriptions.isEmpty()) {
        return completedFuture(Unit.VALUE);
    }
    CompletableFuture<Unit> transferFuture = new CompletableFuture<>();
    UInteger[] subscriptionIdsArray = subscriptions.stream().map(UaSubscription::getSubscriptionId).toArray(UInteger[]::new);
    TransferSubscriptionsRequest request = new TransferSubscriptionsRequest(client.newRequestHeader(session.getAuthenticationToken()), subscriptionIdsArray, true);
    LOGGER.debug("[{}] Sending TransferSubscriptionsRequest...", ctx.getInstanceId());
    stackClient.sendRequest(request).thenApply(TransferSubscriptionsResponse.class::cast).whenComplete((tsr, ex) -> {
        if (tsr != null) {
            List<TransferResult> results = l(tsr.getResults());
            LOGGER.debug("[{}] TransferSubscriptions supported: {}", ctx.getInstanceId(), tsr.getResponseHeader().getServiceResult());
            if (LOGGER.isDebugEnabled()) {
                try {
                    Stream<UInteger> subscriptionIds = subscriptions.stream().map(UaSubscription::getSubscriptionId);
                    Stream<StatusCode> statusCodes = results.stream().map(TransferResult::getStatusCode);
                    // noinspection UnstableApiUsage
                    String[] ss = Streams.zip(subscriptionIds, statusCodes, (i, s) -> String.format("id=%s/%s", i, StatusCodes.lookup(s.getValue()).map(sa -> sa[0]).orElse(s.toString()))).toArray(String[]::new);
                    LOGGER.debug("[{}] TransferSubscriptions results: {}", ctx.getInstanceId(), Arrays.toString(ss));
                } catch (Throwable t) {
                    LOGGER.error("[{}] error logging TransferSubscription results", ctx.getInstanceId(), t);
                }
            }
            client.getConfig().getExecutor().execute(() -> {
                for (int i = 0; i < results.size(); i++) {
                    TransferResult result = results.get(i);
                    if (!result.getStatusCode().isGood()) {
                        UaSubscription subscription = subscriptions.get(i);
                        subscriptionManager.transferFailed(subscription.getSubscriptionId(), result.getStatusCode());
                    }
                }
            });
            transferFuture.complete(Unit.VALUE);
        } else {
            StatusCode statusCode = UaException.extract(ex).map(UaException::getStatusCode).orElse(StatusCode.BAD);
            LOGGER.debug("[{}] TransferSubscriptions not supported: {}", ctx.getInstanceId(), statusCode);
            client.getConfig().getExecutor().execute(() -> {
                // because the list from getSubscriptions() above is a copy.
                for (UaSubscription subscription : subscriptions) {
                    subscriptionManager.transferFailed(subscription.getSubscriptionId(), statusCode);
                }
            });
            // supported but server implementations interpret the spec differently.
            if (statusCode.getValue() == StatusCodes.Bad_NotImplemented || statusCode.getValue() == StatusCodes.Bad_NotSupported || statusCode.getValue() == StatusCodes.Bad_OutOfService || statusCode.getValue() == StatusCodes.Bad_ServiceUnsupported) {
                // One of the expected responses; continue moving through the FSM.
                transferFuture.complete(Unit.VALUE);
            } else {
                // An unexpected response; complete exceptionally and start over.
                // Subsequent runs through the FSM will not attempt transfer because
                // transferFailed() has been called for all the existing subscriptions.
                // This will prevent us from getting stuck in a "loop" attempting to
                // reconnect to a defective server that responds with a channel-level
                // Error message to subscription transfer requests instead of an
                // application-level ServiceFault.
                transferFuture.completeExceptionally(ex);
            }
        }
    });
    return transferFuture;
}

Example 5 with FsmContext

use of com.digitalpetri.strictmachine.FsmContext in project milo by eclipse.

the class SessionFsmFactory method configureCreatingWaitState.

private static void configureCreatingWaitState(FsmBuilder<State, Event> fb, @SuppressWarnings("unused") OpcUaClient client) {
    /* Transitions */
    fb.when(State.CreatingWait).on(Event.CreatingWaitExpired.class).transitionTo(State.Creating);
    fb.when(State.CreatingWait).on(Event.CloseSession.class).transitionTo(State.Inactive);
    /* External Transition Actions */
    fb.onTransitionTo(State.CreatingWait).from(s -> s != State.CreatingWait).viaAny().execute(FsmContext::processShelvedEvents);
    fb.onTransitionTo(State.CreatingWait).from(s -> s != State.CreatingWait).viaAny().execute(ctx -> {
        SessionFuture sessionFuture = new SessionFuture();
        KEY_SESSION_FUTURE.set(ctx, sessionFuture);
        Long waitTime = KEY_WAIT_TIME.get(ctx);
        if (waitTime == null) {
            waitTime = 1L;
        } else {
            waitTime = Math.min(MAX_WAIT_SECONDS, waitTime << 1);
        }
        KEY_WAIT_TIME.set(ctx, waitTime);
        ScheduledFuture<?> waitFuture = client.getConfig().getScheduledExecutor().schedule(() -> ctx.fireEvent(new Event.CreatingWaitExpired()), waitTime, TimeUnit.SECONDS);
        KEY_WAIT_FUTURE.set(ctx, waitFuture);
    });
    fb.onTransitionFrom(State.CreatingWait).to(State.Inactive).via(Event.CloseSession.class).execute(ctx -> {
        ScheduledFuture<?> waitFuture = KEY_WAIT_FUTURE.remove(ctx);
        if (waitFuture != null)
            waitFuture.cancel(false);
        KEY_WAIT_TIME.remove(ctx);
        Event.CloseSession event = (Event.CloseSession) ctx.event();
        client.getConfig().getExecutor().execute(() -> event.future.complete(Unit.VALUE));
    });
    /* Internal Transition Actions */
    fb.onInternalTransition(State.CreatingWait).via(Event.GetSession.class).execute(SessionFsmFactory::handleGetSessionEvent);
    fb.onInternalTransition(State.CreatingWait).via(Event.OpenSession.class).execute(SessionFsmFactory::handleOpenSessionEvent);
}