Examples with Subscription rx.Subscription used on opensource projects

Example 76 with Subscription

use of rx.Subscription in project Hystrix by Netflix.

the class HystrixSampleSseServlet method handleRequest.

/**
     * - maintain an open connection with the client
     * - on initial connection send latest data of each requested event type
     * - subsequently send all changes for each requested event type
     *
     * @param request  incoming HTTP Request
     * @param response outgoing HTTP Response (as a streaming response)
     * @throws javax.servlet.ServletException
     * @throws java.io.IOException
     */
private void handleRequest(HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException {
    final AtomicBoolean moreDataWillBeSent = new AtomicBoolean(true);
    Subscription sampleSubscription = null;
    /* ensure we aren't allowing more connections than we want */
    int numberConnections = incrementAndGetCurrentConcurrentConnections();
    try {
        //may change at runtime, so look this up for each request
        int maxNumberConnectionsAllowed = getMaxNumberConcurrentConnectionsAllowed();
        if (numberConnections > maxNumberConnectionsAllowed) {
            response.sendError(503, "MaxConcurrentConnections reached: " + maxNumberConnectionsAllowed);
        } else {
            /* initialize response */
            response.setHeader("Content-Type", "text/event-stream;charset=UTF-8");
            response.setHeader("Cache-Control", "no-cache, no-store, max-age=0, must-revalidate");
            response.setHeader("Pragma", "no-cache");
            final PrintWriter writer = response.getWriter();
            //since the sample stream is based on Observable.interval, events will get published on an RxComputation thread
            //since writing to the servlet response is blocking, use the Rx IO thread for the write that occurs in the onNext
            sampleSubscription = sampleStream.observeOn(Schedulers.io()).subscribe(new Subscriber<String>() {

                @Override
                public void onCompleted() {
                    logger.error("HystrixSampleSseServlet: ({}) received unexpected OnCompleted from sample stream", getClass().getSimpleName());
                    moreDataWillBeSent.set(false);
                }

                @Override
                public void onError(Throwable e) {
                    moreDataWillBeSent.set(false);
                }

                @Override
                public void onNext(String sampleDataAsString) {
                    if (sampleDataAsString != null) {
                        writer.print("data: " + sampleDataAsString + "\n\n");
                        // explicitly check for client disconnect - PrintWriter does not throw exceptions
                        if (writer.checkError()) {
                            moreDataWillBeSent.set(false);
                        }
                        writer.flush();
                    }
                }
            });
            while (moreDataWillBeSent.get() && !isDestroyed) {
                try {
                    Thread.sleep(pausePollerThreadDelayInMs);
                    //in case stream has not started emitting yet, catch any clients which connect/disconnect before emits start
                    writer.print("ping: \n\n");
                    // explicitly check for client disconnect - PrintWriter does not throw exceptions
                    if (writer.checkError()) {
                        moreDataWillBeSent.set(false);
                    }
                    writer.flush();
                } catch (InterruptedException e) {
                    moreDataWillBeSent.set(false);
                }
            }
        }
    } finally {
        decrementCurrentConcurrentConnections();
        if (sampleSubscription != null && !sampleSubscription.isUnsubscribed()) {
            sampleSubscription.unsubscribe();
        }
    }
}

Example 77 with Subscription

use of rx.Subscription in project Hystrix by Netflix.

the class BucketedCounterStream method unsubscribe.

public void unsubscribe() {
    Subscription s = subscription.get();
    if (s != null) {
        s.unsubscribe();
        subscription.compareAndSet(s, null);
    }
}

Example 78 with Subscription

use of rx.Subscription in project Hystrix by Netflix.

the class RollingConcurrencyStream method unsubscribe.

public void unsubscribe() {
    Subscription s = rollingMaxSubscription.get();
    if (s != null) {
        s.unsubscribe();
        rollingMaxSubscription.compareAndSet(s, null);
    }
}

Example 79 with Subscription

use of rx.Subscription in project Hystrix by Netflix.

the class RollingDistributionStream method unsubscribe.

public void unsubscribe() {
    Subscription s = rollingDistributionSubscription.get();
    if (s != null) {
        s.unsubscribe();
        rollingDistributionSubscription.compareAndSet(s, null);
    }
}

Example 80 with Subscription

use of rx.Subscription in project Hystrix by Netflix.

the class HystrixStreamingOutputProvider method writeTo.

@Override
public void writeTo(HystrixStream o, Class<?> t, Type gt, Annotation[] as, MediaType mediaType, MultivaluedMap<String, Object> httpHeaders, final OutputStream entity) throws IOException {
    Subscription sampleSubscription = null;
    final AtomicBoolean moreDataWillBeSent = new AtomicBoolean(true);
    try {
        sampleSubscription = o.getSampleStream().observeOn(Schedulers.io()).subscribe(new Subscriber<String>() {

            @Override
            public void onCompleted() {
                LOGGER.error("HystrixSampleSseServlet: ({}) received unexpected OnCompleted from sample stream", getClass().getSimpleName());
                moreDataWillBeSent.set(false);
            }

            @Override
            public void onError(Throwable e) {
                moreDataWillBeSent.set(false);
            }

            @Override
            public void onNext(String sampleDataAsString) {
                if (sampleDataAsString != null) {
                    try {
                        entity.write(("data: " + sampleDataAsString + "\n\n").getBytes());
                        entity.flush();
                    } catch (IOException ioe) {
                        moreDataWillBeSent.set(false);
                    }
                }
            }
        });
        while (moreDataWillBeSent.get()) {
            try {
                Thread.sleep(o.getPausePollerThreadDelayInMs());
            } catch (InterruptedException e) {
                moreDataWillBeSent.set(false);
            }
        }
    } finally {
        o.getConcurrentConnections().decrementAndGet();
        if (sampleSubscription != null && !sampleSubscription.isUnsubscribed()) {
            sampleSubscription.unsubscribe();
        }
    }
}