Examples with DisableBackPressureOperator io.reactivx.mantis.operators.DisableBackPressureOperator used on opensource projects

Example 1 with DisableBackPressureOperator

use of io.reactivx.mantis.operators.DisableBackPressureOperator in project mantis by Netflix.

the class ObservableTrigger method groupTrigger.

private static <K, V> PushTrigger<KeyValuePair<K, V>> groupTrigger(final String name, final Observable<GroupedObservable<K, V>> o, final Action0 doOnComplete, final Action1<Throwable> doOnError, final long groupExpirySeconds, final Func1<K, byte[]> keyEncoder, final HashFunction hashFunction) {
    final AtomicReference<Subscription> subRef = new AtomicReference<>();
    final Gauge subscriptionActive;
    Metrics metrics = new Metrics.Builder().name("ObservableTrigger_" + name).addGauge("subscriptionActive").build();
    subscriptionActive = metrics.getGauge("subscriptionActive");
    Action1<MonitoredQueue<KeyValuePair<K, V>>> doOnStart = new Action1<MonitoredQueue<KeyValuePair<K, V>>>() {

        @Override
        public void call(final MonitoredQueue<KeyValuePair<K, V>> queue) {
            subRef.set(o.observeOn(Schedulers.computation()).doOnSubscribe(() -> {
                logger.info("Subscription is ACTIVE for observable trigger with name: " + name);
                subscriptionActive.set(1);
            }).doOnUnsubscribe(() -> {
                logger.info("Subscription is INACTIVE for observable trigger with name: " + name);
                subscriptionActive.set(0);
            }).flatMap((final GroupedObservable<K, V> group) -> {
                final byte[] keyBytes = keyEncoder.call(group.getKey());
                final long keyBytesHashed = hashFunction.computeHash(keyBytes);
                return group.timeout(groupExpirySeconds, TimeUnit.SECONDS, (Observable<? extends V>) Observable.empty()).lift(new DisableBackPressureOperator<V>()).buffer(250, TimeUnit.MILLISECONDS).filter((List<V> t1) -> t1 != null && !t1.isEmpty()).map((List<V> list) -> {
                    List<KeyValuePair<K, V>> keyPairList = new ArrayList<>(list.size());
                    for (V data : list) {
                        keyPairList.add(new KeyValuePair<K, V>(keyBytesHashed, keyBytes, data));
                    }
                    return keyPairList;
                });
            }).subscribe((List<KeyValuePair<K, V>> list) -> {
                for (KeyValuePair<K, V> data : list) {
                    queue.write(data);
                }
            }, (Throwable e) -> {
                logger.warn("Observable used to push data errored, on server with name: " + name, e);
                if (doOnError != null) {
                    doOnError.call(e);
                }
            }, () -> {
                logger.info("Observable used to push data completed, on server with name: " + name);
                if (doOnComplete != null) {
                    doOnComplete.call();
                }
            }));
        }
    };
    Action1<MonitoredQueue<KeyValuePair<K, V>>> doOnStop = new Action1<MonitoredQueue<KeyValuePair<K, V>>>() {

        @Override
        public void call(MonitoredQueue<KeyValuePair<K, V>> t1) {
            if (subRef.get() != null) {
                logger.warn("Connections from next stage has dropped to 0. Do not propagate unsubscribe");
            // subRef.get().unsubscribe();
            }
        }
    };
    return new PushTrigger<>(doOnStart, doOnStop, metrics);
}

Example 2 with DisableBackPressureOperator

use of io.reactivx.mantis.operators.DisableBackPressureOperator in project mantis by Netflix.

the class ServeGroupedObservable method applySlottingSideEffectToObservable.

private void applySlottingSideEffectToObservable(Observable<Observable<GroupedObservable<String, V>>> o, final Observable<Integer> minConnectionsToSubscribe) {
    final AtomicInteger currentMinConnectionsToSubscribe = new AtomicInteger();
    minConnectionsToSubscribe.subscribe(new Action1<Integer>() {

        @Override
        public void call(Integer t1) {
            currentMinConnectionsToSubscribe.set(t1);
        }
    });
    Observable<Observable<List<Group<String, V>>>> listOfGroups = o.map(new Func1<Observable<GroupedObservable<String, V>>, Observable<List<Group<String, V>>>>() {

        @Override
        public Observable<List<Group<String, V>>> call(Observable<GroupedObservable<String, V>> og) {
            return og.flatMap(new Func1<GroupedObservable<String, V>, Observable<List<Group<String, V>>>>() {

                @Override
                public Observable<List<Group<String, V>>> call(final GroupedObservable<String, V> group) {
                    final byte[] keyBytes = keyEncoder.encode(group.getKey());
                    final String keyValue = group.getKey();
                    return group.doOnUnsubscribe(new Action0() {

                        @Override
                        public void call() {
                            // logger.info("Expiring group stage in serveGroupedObservable " + group.getKey());
                            groupsExpiredCounter.increment();
                        }
                    }).timeout(expiryInSecs, TimeUnit.SECONDS, (Observable<? extends V>) Observable.empty()).materialize().lift(new DisableBackPressureOperator<Notification<V>>()).buffer(groupBufferTimeMSec, TimeUnit.MILLISECONDS).filter(new Func1<List<Notification<V>>, Boolean>() {

                        @Override
                        public Boolean call(List<Notification<V>> t1) {
                            return t1 != null && !t1.isEmpty();
                        }
                    }).map(new Func1<List<Notification<V>>, List<Group<String, V>>>() {

                        @Override
                        public List<Group<String, V>> call(List<Notification<V>> notifications) {
                            List<Group<String, V>> groups = new ArrayList<>(notifications.size());
                            for (Notification<V> notification : notifications) {
                                groups.add(new Group<String, V>(keyValue, keyBytes, notification));
                            }
                            return groups;
                        }
                    });
                }
            });
        }
    });
    final Observable<List<Group<String, V>>> withSideEffects = Observable.merge(listOfGroups).doOnEach(new Observer<List<Group<String, V>>>() {

        @Override
        public void onCompleted() {
            slottingStrategy.completeAllConnections();
        }

        @Override
        public void onError(Throwable e) {
            e.printStackTrace();
            slottingStrategy.errorAllConnections(e);
        }

        @Override
        public void onNext(List<Group<String, V>> listOfGroups) {
            for (Group<String, V> group : listOfGroups) {
                slottingStrategy.writeOnSlot(group.getKeyBytes(), group);
            }
        }
    });
    final MutableReference<Subscription> subscriptionRef = new MutableReference<>();
    final AtomicInteger connectionCount = new AtomicInteger(0);
    final AtomicBoolean isSubscribed = new AtomicBoolean();
    slottingStrategy.registerDoOnEachConnectionAdded(new Action0() {

        @Override
        public void call() {
            Integer minNeeded = currentMinConnectionsToSubscribe.get();
            Integer current = connectionCount.incrementAndGet();
            if (current >= minNeeded) {
                if (isSubscribed.compareAndSet(false, true)) {
                    logger.info("MinConnectionsToSubscribe: " + minNeeded + ", has been met, subscribing to observable, current connection count: " + current);
                    subscriptionRef.setValue(withSideEffects.subscribe());
                }
            } else {
                logger.info("MinConnectionsToSubscribe: " + minNeeded + ", has NOT been met, current connection count: " + current);
            }
        }
    });
    slottingStrategy.registerDoAfterLastConnectionRemoved(new Action0() {

        @Override
        public void call() {
            subscriptionRef.getValue().unsubscribe();
            logger.info("All connections deregistered, unsubscribed to observable, resetting current connection count: 0");
            connectionCount.set(0);
            isSubscribed.set(false);
        }
    });
}

Example 3 with DisableBackPressureOperator

use of io.reactivx.mantis.operators.DisableBackPressureOperator in project mantis by Netflix.

the class ServerSentEventRequestHandler method handle.

@Override
public Observable<Void> handle(HttpServerRequest<ByteBuf> request, final HttpServerResponse<ServerSentEvent> response) {
    InetSocketAddress socketAddress = (InetSocketAddress) response.getChannel().remoteAddress();
    LOG.info("HTTP SSE connection received from " + socketAddress.getAddress() + ":" + socketAddress.getPort() + "  queryParams: " + request.getQueryParameters());
    final String socketAddrStr = socketAddress.getAddress().toString();
    final WritableEndpoint<String> sn = new WritableEndpoint<>(socketAddress.getHostString(), socketAddress.getPort(), Endpoint.uniqueHost(socketAddress.getHostString(), socketAddress.getPort(), null));
    final Map<String, List<String>> queryParameters = request.getQueryParameters();
    final SlotAssignmentManager<String> slotMgr = ssm.registerServer(sn, queryParameters);
    final AtomicLong lastResponseFlush = new AtomicLong();
    lastResponseFlush.set(-1);
    final AtomicLong lastResponseSent = new AtomicLong(-1);
    // copy reference, then apply request specific filters, sampling
    Observable<T> requestObservable = observableToServe;
    // decouple the observable on a separate thread and add backpressure handling
    // ServiceRegistry.INSTANCE.getPropertiesService().getStringValue("sse.decouple", "false");
    String decoupleSSE = "false";
    if ("true".equals(decoupleSSE)) {
        final BasicTag sockAddrTag = new BasicTag("sockAddr", Optional.ofNullable(socketAddrStr).orElse("none"));
        requestObservable = requestObservable.lift(new DropOperator<T>("outgoing_ServerSentEventRequestHandler", sockAddrTag)).observeOn(Schedulers.io());
    }
    response.getHeaders().set("Access-Control-Allow-Origin", "*");
    response.getHeaders().set("content-type", "text/event-stream");
    response.getHeaders().set("Cache-Control", "no-cache, no-store, max-age=0, must-revalidate");
    response.getHeaders().set("Pragma", "no-cache");
    response.flush();
    String uniqueClientId = socketAddrStr;
    if (queryParameters != null && queryParameters.containsKey(CLIENT_ID_PARAM)) {
        // enablePings
        uniqueClientId = queryParameters.get(CLIENT_ID_PARAM).get(0);
    }
    if (queryParameters != null && queryParameters.containsKey(FORMAT_PARAM)) {
        format = queryParameters.get(FORMAT_PARAM).get(0);
    }
    if (queryParameters != null && requestPreprocessor != null) {
        requestPreprocessor.call(queryParameters, context);
    }
    // apply sampling, milli, then seconds
    if (queryParameters != null && queryParameters.containsKey(SAMPLE_PARAM_MSEC)) {
        // apply sampling rate
        int samplingRate = Integer.parseInt(queryParameters.get(SAMPLE_PARAM_MSEC).get(0));
        requestObservable = requestObservable.sample(samplingRate, TimeUnit.MILLISECONDS);
    }
    if (queryParameters != null && queryParameters.containsKey(SAMPLE_PARAM)) {
        // apply sampling rate
        int samplingRate = Integer.parseInt(queryParameters.get(SAMPLE_PARAM).get(0));
        requestObservable = requestObservable.sample(samplingRate, TimeUnit.SECONDS);
    }
    if (queryParameters != null && queryParameters.containsKey(ENABLE_PINGS_PARAM)) {
        // enablePings
        String enablePings = queryParameters.get(ENABLE_PINGS_PARAM).get(0);
        if ("true".equalsIgnoreCase(enablePings)) {
            pingsEnabled = true;
        } else {
            pingsEnabled = false;
        }
    }
    if (queryParameters != null && queryParameters.containsKey("delay")) {
        // apply flush
        try {
            int flushInterval = Integer.parseInt(queryParameters.get("delay").get(0));
            if (flushInterval >= 50) {
                flushIntervalMillis = flushInterval;
            } else {
                LOG.warn("delay parameter too small " + flushInterval + " min. is 100");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    final byte[] delimiter = queryParameters != null && queryParameters.containsKey(MantisSSEConstants.MANTIS_COMPRESSION_DELIMITER) && queryParameters.get(MantisSSEConstants.MANTIS_COMPRESSION_DELIMITER).get(0) != null ? queryParameters.get(MantisSSEConstants.MANTIS_COMPRESSION_DELIMITER).get(0).getBytes() : null;
    Tag[] tags = new Tag[2];
    final String clientId = Optional.ofNullable(uniqueClientId).orElse("none");
    final String sockAddr = Optional.ofNullable(socketAddrStr).orElse("none");
    tags[0] = new BasicTag("clientId", clientId);
    tags[1] = new BasicTag("sockAddr", sockAddr);
    Metrics sseSinkMetrics = new Metrics.Builder().id("ServerSentEventRequestHandler", tags).addCounter("processedCounter").addCounter("pingCounter").addCounter("errorCounter").addCounter("droppedCounter").addCounter("flushCounter").build();
    final Counter msgProcessedCounter = sseSinkMetrics.getCounter("processedCounter");
    final Counter pingCounter = sseSinkMetrics.getCounter("pingCounter");
    final Counter errorCounter = sseSinkMetrics.getCounter("errorCounter");
    final Counter droppedWrites = sseSinkMetrics.getCounter("droppedCounter");
    final Counter flushCounter = sseSinkMetrics.getCounter("flushCounter");
    // get predicate, defaults to return true for all T
    Func1<T, Boolean> filterFunction = new Func1<T, Boolean>() {

        @Override
        public Boolean call(T t1) {
            return true;
        }
    };
    if (queryParameters != null && predicate != null) {
        filterFunction = predicate.getPredicate().call(queryParameters);
    }
    final Subscription timerSubscription = Observable.interval(1, TimeUnit.SECONDS).doOnNext(new Action1<Long>() {

        @Override
        public void call(Long t1) {
            long currentTime = System.currentTimeMillis();
            if (pingsEnabled && (lastResponseSent.get() == -1 || currentTime > lastResponseSent.get() + PING_INTERVAL)) {
                pingCounter.increment();
                response.writeStringAndFlush(PING);
                lastResponseSent.set(currentTime);
            }
        }
    }).subscribe();
    return requestObservable.filter(filterFunction).map(encoder).lift(new DisableBackPressureOperator<String>()).buffer(flushIntervalMillis, TimeUnit.MILLISECONDS).flatMap(new Func1<List<String>, Observable<Void>>() {

        @Override
        public Observable<Void> call(List<String> valueList) {
            if (response.isCloseIssued() || !response.getChannel().isActive()) {
                LOG.info("Client closed detected, throwing closed channel exception");
                return Observable.error(new ClosedChannelException());
            }
            List<String> filteredList = valueList.stream().filter(e -> {
                return slotMgr.filter(sn, e.getBytes());
            }).collect(Collectors.toList());
            if (response.getChannel().isWritable()) {
                flushCounter.increment();
                if (format.equals(BINARY_FORMAT)) {
                    boolean useSnappy = true;
                    try {
                        String compressedList = delimiter == null ? CompressionUtils.compressAndBase64Encode(filteredList, useSnappy) : CompressionUtils.compressAndBase64Encode(filteredList, useSnappy, delimiter);
                        StringBuilder sb = new StringBuilder(3);
                        sb.append(SSE_DATA_PREFIX);
                        sb.append(compressedList);
                        sb.append(TWO_NEWLINES);
                        msgProcessedCounter.increment(valueList.size());
                        lastResponseSent.set(System.currentTimeMillis());
                        return response.writeStringAndFlush(sb.toString());
                    } catch (Exception e) {
                        LOG.warn("Could not compress data" + e.getMessage());
                        droppedWrites.increment(valueList.size());
                        return Observable.empty();
                    }
                } else {
                    int noOfMsgs = 0;
                    StringBuilder sb = new StringBuilder(valueList.size() * 3);
                    for (String s : filteredList) {
                        sb.append(SSE_DATA_PREFIX);
                        sb.append(s);
                        sb.append(TWO_NEWLINES);
                        noOfMsgs++;
                    }
                    msgProcessedCounter.increment(noOfMsgs);
                    lastResponseSent.set(System.currentTimeMillis());
                    return response.writeStringAndFlush(sb.toString());
                }
            } else {
                // 
                droppedWrites.increment(filteredList.size());
            }
            return Observable.empty();
        }
    }).onErrorResumeNext(new Func1<Throwable, Observable<? extends Void>>() {

        @Override
        public Observable<? extends Void> call(Throwable throwable) {
            Throwable cause = throwable.getCause();
            // ignore closed channel exceptions, this is
            // when the connection was closed on the client
            // side without informing the server
            errorCounter.increment();
            if (cause != null && !(cause instanceof ClosedChannelException)) {
                LOG.warn("Error detected in SSE sink", cause);
                if (errorEncoder != null) {
                    // write error out on connection
                    // response.writeAndFlush(errorEncoder.call(throwable));
                    ByteBuf errType = response.getAllocator().buffer().writeBytes("error: ".getBytes());
                    ByteBuf errRes = response.getAllocator().buffer().writeBytes((errorEncoder.call(throwable)).getBytes());
                    response.writeAndFlush(ServerSentEvent.withEventType(errType, errRes));
                }
                throwable.printStackTrace();
            }
            if (requestPostprocessor != null && queryParameters != null) {
                requestPostprocessor.call(queryParameters, context);
            }
            ssm.deregisterServer(sn, queryParameters);
            timerSubscription.unsubscribe();
            return Observable.error(throwable);
        }
    });
}

Example 4 with DisableBackPressureOperator

use of io.reactivx.mantis.operators.DisableBackPressureOperator in project mantis by Netflix.

the class RemoteObservableConnectionHandler method serveNestedObservable.

@SuppressWarnings({ "unchecked", "rawtypes" })
private <T> Subscription serveNestedObservable(final Observable<T> observable, final ObservableConnection<RemoteRxEvent, List<RemoteRxEvent>> connection, final RemoteRxEvent event, final Func1<Map<String, String>, Func1<T, Boolean>> filterFunction, final Encoder<T> encoder, final ServeNestedObservable<Observable<T>> serveConfig, final WritableEndpoint<Observable<T>> endpoint) {
    final MutableReference<Subscription> subReference = new MutableReference<>();
    subReference.setValue(observable.filter(filterFunction.call(event.getSubscribeParameters())).doOnCompleted(new Action0() {

        @Override
        public void call() {
            logger.info("OnCompleted recieved in serveNestedObservable, sending to client.");
        }
    }).doOnError(new Action1<Throwable>() {

        @Override
        public void call(Throwable t1) {
            logger.info("OnError received in serveNestedObservable, sending to client: ", t1);
        }
    }).map(new Func1<T, byte[]>() {

        @Override
        public byte[] call(T t1) {
            return encoder.encode(t1);
        }
    }).materialize().map(new Func1<Notification<byte[]>, RemoteRxEvent>() {

        @Override
        public RemoteRxEvent call(Notification<byte[]> notification) {
            if (notification.getKind() == Notification.Kind.OnNext) {
                return RemoteRxEvent.next(event.getName(), notification.getValue());
            } else if (notification.getKind() == Notification.Kind.OnError) {
                return RemoteRxEvent.error(event.getName(), RemoteObservable.fromThrowableToBytes(notification.getThrowable()));
            } else if (notification.getKind() == Notification.Kind.OnCompleted) {
                return RemoteRxEvent.completed(event.getName());
            } else {
                throw new RuntimeException("Unsupported notification kind: " + notification.getKind());
            }
        }
    }).lift(new DisableBackPressureOperator<RemoteRxEvent>()).buffer(writeBufferTimeMSec, TimeUnit.MILLISECONDS).filter(new Func1<List<RemoteRxEvent>, Boolean>() {

        @Override
        public Boolean call(List<RemoteRxEvent> t1) {
            return t1 != null && !t1.isEmpty();
        }
    }).filter(new Func1<List<RemoteRxEvent>, Boolean>() {

        @Override
        public Boolean call(List<RemoteRxEvent> t1) {
            return t1 != null && !t1.isEmpty();
        }
    }).subscribe(new WriteBytesObserver(connection, subReference, serverMetrics, serveConfig.getSlottingStrategy(), endpoint)));
    return subReference.getValue();
}