Examples with PublisherOperator io.servicetalk.concurrent.api.PublisherOperator used on opensource projects

Example 1 with PublisherOperator

use of io.servicetalk.concurrent.api.PublisherOperator in project servicetalk by apple.

the class AbstractPublisherOffloadingTest method testOffloading.

protected int testOffloading(BiFunction<Publisher<String>, Executor, Publisher<String>> offloadingFunction, TerminalOperation terminal) throws InterruptedException {
    Runnable appCode = () -> {
        try {
            // Insert a custom value into AsyncContext map
            AsyncContext.put(ASYNC_CONTEXT_CUSTOM_KEY, ASYNC_CONTEXT_VALUE);
            capture(CaptureSlot.APP);
            // Add thread recording test points
            final Publisher<String> original = testPublisher.liftSync((PublisherOperator<? super String, String>) subscriber -> {
                capture(CaptureSlot.OFFLOADED_SUBSCRIBE);
                return subscriber;
            }).beforeOnSubscribe(cancellable -> capture(CaptureSlot.ORIGINAL_ON_SUBSCRIBE)).beforeRequest((requested) -> capture(CaptureSlot.OFFLOADED_REQUEST)).beforeOnNext((item) -> capture(CaptureSlot.ORIGINAL_ON_NEXT)).beforeFinally(new TerminalSignalConsumer() {

                @Override
                public void onComplete() {
                    capture(CaptureSlot.ORIGINAL_ON_COMPLETE);
                }

                @Override
                public void onError(final Throwable throwable) {
                    capture(CaptureSlot.ORIGINAL_ON_ERROR);
                }

                @Override
                public void cancel() {
                    capture(CaptureSlot.OFFLOADED_CANCEL);
                }
            });
            // Perform offloading and add more thread recording test points
            Publisher<String> offloaded = offloadingFunction.apply(original, testExecutor.executor()).liftSync((PublisherOperator<? super String, String>) subscriber -> {
                capture(CaptureSlot.ORIGINAL_SUBSCRIBE);
                return subscriber;
            }).beforeOnSubscribe(cancellable -> capture(CaptureSlot.OFFLOADED_ON_SUBSCRIBE)).beforeRequest((requested) -> capture(CaptureSlot.ORIGINAL_REQUEST)).beforeOnNext((item) -> capture(CaptureSlot.OFFLOADED_ON_NEXT)).beforeFinally(new TerminalSignalConsumer() {

                @Override
                public void onComplete() {
                    capture(CaptureSlot.OFFLOADED_ON_COMPLETE);
                }

                @Override
                public void onError(final Throwable throwable) {
                    capture(CaptureSlot.OFFLOADED_ON_ERROR);
                }

                @Override
                public void cancel() {
                    capture(CaptureSlot.ORIGINAL_CANCEL);
                }
            });
            // subscribe
            toSource(offloaded).subscribe(testSubscriber);
            assertThat("Unexpected tasks " + testExecutor.executor().queuedTasksPending(), testExecutor.executor().queuedTasksPending(), lessThan(2));
            if (1 == testExecutor.executor().queuedTasksPending()) {
                // execute offloaded subscribe
                testExecutor.executor().executeNextTask();
            }
            PublisherSource.Subscription subscription = testSubscriber.awaitSubscription();
            assertThat("No Subscription", subscription, notNullValue());
            testPublisher.awaitSubscribed();
            assertThat("Source is not subscribed", testPublisher.isSubscribed());
            assertThat("Thread was interrupted", !Thread.currentThread().isInterrupted());
            // generate demand
            subscription.request(MAX_VALUE);
            assertThat("Unexpected tasks " + testExecutor.executor().queuedTasksPending(), testExecutor.executor().queuedTasksPending(), lessThan(2));
            if (1 == testExecutor.executor().queuedTasksPending()) {
                // execute offloaded request
                testExecutor.executor().executeNextTask();
            }
            testSubscription.awaitRequestN(1);
            // perform terminal
            switch(terminal) {
                case CANCEL:
                    subscription.cancel();
                    break;
                case COMPLETE:
                    testPublisher.onNext(ITEM_VALUE);
                    assertThat("Unexpected tasks " + testExecutor.executor().queuedTasksPending(), testExecutor.executor().queuedTasksPending(), lessThan(2));
                    if (1 == testExecutor.executor().queuedTasksPending()) {
                        // execute offloaded onNext
                        testExecutor.executor().executeNextTask();
                    }
                    String result = testSubscriber.takeOnNext();
                    assertThat("result is unexpected value", result, sameInstance(ITEM_VALUE));
                    testPublisher.onComplete();
                    break;
                case ERROR:
                    testPublisher.onError(DELIBERATE_EXCEPTION);
                    break;
                default:
                    throw new AssertionError("unexpected terminal mode");
            }
            assertThat("Unexpected tasks " + testExecutor.executor().queuedTasksPending(), testExecutor.executor().queuedTasksPending(), lessThan(2));
            if (1 == testExecutor.executor().queuedTasksPending()) {
                // execute offloaded terminal
                testExecutor.executor().executeNextTask();
            }
        } catch (Throwable all) {
            AbstractOffloadingTest.LOGGER.warn("Unexpected throwable", all);
            testSubscriber.onError(all);
        }
    };
    APP_EXECUTOR_EXT.executor().execute(appCode);
    // Ensure we reached the correct terminal condition
    switch(terminal) {
        case CANCEL:
            testSubscription.awaitCancelled();
            break;
        case ERROR:
            Throwable thrown = testSubscriber.awaitOnError();
            assertThat("unexpected exception " + thrown, thrown, sameInstance(DELIBERATE_EXCEPTION));
            break;
        case COMPLETE:
            testSubscriber.awaitOnComplete();
            break;
        default:
            throw new AssertionError("unexpected terminal mode");
    }
    // Ensure that Async Context Map was correctly set during signals
    ContextMap appMap = capturedContexts.captured(CaptureSlot.APP);
    assertThat(appMap, notNullValue());
    ContextMap subscribeMap = capturedContexts.captured(CaptureSlot.ORIGINAL_SUBSCRIBE);
    assertThat(subscribeMap, notNullValue());
    assertThat("Map was shared not copied", subscribeMap, not(sameInstance(appMap)));
    assertThat("Missing custom async context entry ", subscribeMap.get(ASYNC_CONTEXT_CUSTOM_KEY), sameInstance(ASYNC_CONTEXT_VALUE));
    EnumSet<CaptureSlot> checkSlots = EnumSet.complementOf(EnumSet.of(CaptureSlot.APP, CaptureSlot.ORIGINAL_SUBSCRIBE));
    checkSlots.stream().filter(slot -> null != capturedContexts.captured(slot)).forEach(slot -> {
        ContextMap map = capturedContexts.captured(slot);
        assertThat("Context map was not captured", map, is(notNullValue()));
        assertThat("Custom key missing from context map", map.containsKey(ASYNC_CONTEXT_CUSTOM_KEY));
        assertThat("Unexpected context map @ slot " + slot + " : " + map, map, sameInstance(subscribeMap));
    });
    assertThat("Pending offloading", testExecutor.executor().queuedTasksPending(), is(0));
    return testExecutor.executor().queuedTasksExecuted();
}