Java Code Examples for reactor.core.publisher.Mono#onErrorResume()

The following examples show how to use reactor.core.publisher.Mono#onErrorResume() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source File: DefaultWebClient.java    From spring-analysis-note with MIT License 6 votes vote down vote up 
private <T extends Publisher<?>> T handleBody(ClientResponse response,
		T bodyPublisher, Function<Mono<? extends Throwable>, T> errorFunction) {

	if (HttpStatus.resolve(response.rawStatusCode()) != null) {
		for (StatusHandler handler : this.statusHandlers) {
			if (handler.test(response.statusCode())) {
				HttpRequest request = this.requestSupplier.get();
				Mono<? extends Throwable> exMono = handler.apply(response, request);
				exMono = exMono.flatMap(ex -> drainBody(response, ex));
				exMono = exMono.onErrorResume(ex -> drainBody(response, ex));
				T result = errorFunction.apply(exMono);
				return insertCheckpoint(result, response.statusCode(), request);
			}
		}
		return bodyPublisher;
	}
	else {
		return errorFunction.apply(createResponseException(response, this.requestSupplier.get()));
	}
}
Example 2
Source File: ExceptionHandlingWebHandler.java    From spring-analysis-note with MIT License 6 votes vote down vote up 
@Override
public Mono<Void> handle(ServerWebExchange exchange) {

	Mono<Void> completion;
	try {
		completion = super.handle(exchange);
	}
	catch (Throwable ex) {
		completion = Mono.error(ex);
	}

	for (WebExceptionHandler handler : this.exceptionHandlers) {
		completion = completion.onErrorResume(ex -> handler.handle(exchange, ex));
	}

	return completion;
}
Example 3
Source File: DefaultWebClient.java    From java-technology-stack with MIT License 6 votes vote down vote up 
private <T extends Publisher<?>> T handleBody(ClientResponse response,
		T bodyPublisher, Function<Mono<? extends Throwable>, T> errorFunction) {

	if (HttpStatus.resolve(response.rawStatusCode()) != null) {
		for (StatusHandler handler : this.statusHandlers) {
			if (handler.test(response.statusCode())) {
				HttpRequest request = this.requestSupplier.get();
				Mono<? extends Throwable> exMono = handler.apply(response, request);
				exMono = exMono.flatMap(ex -> drainBody(response, ex));
				exMono = exMono.onErrorResume(ex -> drainBody(response, ex));
				return errorFunction.apply(exMono);
			}
		}
		return bodyPublisher;
	}
	else {
		return errorFunction.apply(createResponseException(response, this.requestSupplier.get()));
	}
}
Example 4
Source File: ExceptionHandlingWebHandler.java    From java-technology-stack with MIT License 6 votes vote down vote up 
@Override
public Mono<Void> handle(ServerWebExchange exchange) {

	Mono<Void> completion;
	try {
		completion = super.handle(exchange);
	}
	catch (Throwable ex) {
		completion = Mono.error(ex);
	}

	for (WebExceptionHandler handler : this.exceptionHandlers) {
		completion = completion.onErrorResume(ex -> handler.handle(exchange, ex));
	}

	return completion;
}
Example 5
Source File: ReactiveResilience4JCircuitBreaker.java    From spring-cloud-circuitbreaker with Apache License 2.0 6 votes vote down vote up 
@Override
public <T> Mono<T> run(Mono<T> toRun, Function<Throwable, Mono<T>> fallback) {
	io.github.resilience4j.circuitbreaker.CircuitBreaker defaultCircuitBreaker = registry
			.circuitBreaker(id, config.getCircuitBreakerConfig());
	circuitBreakerCustomizer
			.ifPresent(customizer -> customizer.customize(defaultCircuitBreaker));
	Mono<T> toReturn = toRun
			.transform(CircuitBreakerOperator.of(defaultCircuitBreaker))
			.timeout(config.getTimeLimiterConfig().getTimeoutDuration())
			// Since we are using the Mono timeout we need to tell the circuit breaker
			// about the error
			.doOnError(TimeoutException.class,
					t -> defaultCircuitBreaker.onError(config.getTimeLimiterConfig()
							.getTimeoutDuration().toMillis(), TimeUnit.MILLISECONDS,
							t));
	if (fallback != null) {
		toReturn = toReturn.onErrorResume(fallback);
	}
	return toReturn;
}
Example 6
Source File: R045_ErrorHandling.java    From reactor-workshop with GNU General Public License v3.0 5 votes vote down vote up 
/**
 * TODO Where's the 'Failed' exception? Add some logging
 */
@Test
public void onErrorResume() throws Exception {
	//given
	AtomicBoolean cheapFlag = new AtomicBoolean();
	AtomicBoolean expensiveFlag = new AtomicBoolean();

	Mono<String> cheapButDangerous = Mono.fromCallable(() -> {
		cheapFlag.set(true);
		throw new RuntimeException("Failed");
	});

	Mono<String> expensive = Mono.fromCallable(() -> {
		expensiveFlag.set(true);
		return "Expensive";
	});

	//when
	final Mono<String> withError = cheapButDangerous
			.onErrorResume(e -> expensive);

	//then
	withError
			.as(StepVerifier::create)
			.expectNext("Expensive")
			.verifyComplete();
	assertThat(cheapFlag).isTrue();
	assertThat(expensiveFlag).isTrue();
}
Example 7
Source File: ReactiveSentinelCircuitBreaker.java    From spring-cloud-alibaba with Apache License 2.0 5 votes vote down vote up 
@Override
public <T> Mono<T> run(Mono<T> toRun, Function<Throwable, Mono<T>> fallback) {
	Mono<T> toReturn = toRun.transform(new SentinelReactorTransformer<>(
			new EntryConfig(resourceName, entryType)));
	if (fallback != null) {
		toReturn = toReturn.onErrorResume(fallback);
	}
	return toReturn;
}
Example 8
Source File: HttpClientConnect.java    From reactor-netty with Apache License 2.0 5 votes vote down vote up 
@Override
protected Mono<? extends Connection> connect() {
	HttpClientConfig config = configuration();

	Mono<? extends Connection> mono;
	if (config.deferredConf != null) {
		return config.deferredConf.apply(Mono.just(config))
		           .flatMap(MonoHttpConnect::new);
	}
	else {
		mono = new MonoHttpConnect(config);
	}

	if (config.doOnConnect() != null) {
		mono = mono.doOnSubscribe(s -> config.doOnConnect().accept(config));
	}

	if (config.doOnRequestError != null) {
		mono = mono.onErrorResume(error ->
				Mono.subscriberContext()
				    .doOnNext(ctx -> config.doOnRequestError.accept(new FailedHttpClientRequest(ctx, config), error))
				    .then(Mono.error(error)));
	}

	if (config.connector != null) {
		mono = config.connector.apply(mono);
	}
	return mono;
}
Example 9
Source File: RecoveryFunction.java    From resilience4j with Apache License 2.0 5 votes vote down vote up 
default Mono<? super O> onErrorResume(Mono<? super O> mono) {
    return mono.onErrorResume(t -> {
        O fallbackValue;
        try {
            Throwable actual = Optional.ofNullable(t.getCause()).orElse(t);
            fallbackValue = apply(actual);
        } catch (Exception e) {
            return Mono.error(e);
        }
        return Mono.just(fallbackValue);
    });
}
Example 10
Source File: AbstractMessageReaderArgumentResolver.java    From spring-analysis-note with MIT License 4 votes vote down vote up 
/**
 * Read the body from a method argument with {@link HttpMessageReader}.
 * @param bodyParam represents the element type for the body
 * @param actualParam the actual method argument type; possibly different
 * from {@code bodyParam}, e.g. for an {@code HttpEntity} argument
 * @param isBodyRequired true if the body is required
 * @param bindingContext the binding context to use
 * @param exchange the current exchange
 * @return a Mono with the value to use for the method argument
 * @since 5.0.2
 */
protected Mono<Object> readBody(MethodParameter bodyParam, @Nullable MethodParameter actualParam,
		boolean isBodyRequired, BindingContext bindingContext, ServerWebExchange exchange) {

	ResolvableType bodyType = ResolvableType.forMethodParameter(bodyParam);
	ResolvableType actualType = (actualParam != null ? ResolvableType.forMethodParameter(actualParam) : bodyType);
	Class<?> resolvedType = bodyType.resolve();
	ReactiveAdapter adapter = (resolvedType != null ? getAdapterRegistry().getAdapter(resolvedType) : null);
	ResolvableType elementType = (adapter != null ? bodyType.getGeneric() : bodyType);
	isBodyRequired = isBodyRequired || (adapter != null && !adapter.supportsEmpty());

	ServerHttpRequest request = exchange.getRequest();
	ServerHttpResponse response = exchange.getResponse();

	MediaType contentType = request.getHeaders().getContentType();
	MediaType mediaType = (contentType != null ? contentType : MediaType.APPLICATION_OCTET_STREAM);
	Object[] hints = extractValidationHints(bodyParam);

	if (mediaType.isCompatibleWith(MediaType.APPLICATION_FORM_URLENCODED)) {
		return Mono.error(new IllegalStateException(
				"In a WebFlux application, form data is accessed via ServerWebExchange.getFormData()."));
	}

	if (logger.isDebugEnabled()) {
		logger.debug(exchange.getLogPrefix() + (contentType != null ?
				"Content-Type:" + contentType :
				"No Content-Type, using " + MediaType.APPLICATION_OCTET_STREAM));
	}

	for (HttpMessageReader<?> reader : getMessageReaders()) {
		if (reader.canRead(elementType, mediaType)) {
			Map<String, Object> readHints = Hints.from(Hints.LOG_PREFIX_HINT, exchange.getLogPrefix());
			if (adapter != null && adapter.isMultiValue()) {
				if (logger.isDebugEnabled()) {
					logger.debug(exchange.getLogPrefix() + "0..N [" + elementType + "]");
				}
				Flux<?> flux = reader.read(actualType, elementType, request, response, readHints);
				flux = flux.onErrorResume(ex -> Flux.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					flux = flux.switchIfEmpty(Flux.error(() -> handleMissingBody(bodyParam)));
				}
				if (hints != null) {
					flux = flux.doOnNext(target ->
							validate(target, hints, bodyParam, bindingContext, exchange));
				}
				return Mono.just(adapter.fromPublisher(flux));
			}
			else {
				// Single-value (with or without reactive type wrapper)
				if (logger.isDebugEnabled()) {
					logger.debug(exchange.getLogPrefix() + "0..1 [" + elementType + "]");
				}
				Mono<?> mono = reader.readMono(actualType, elementType, request, response, readHints);
				mono = mono.onErrorResume(ex -> Mono.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					mono = mono.switchIfEmpty(Mono.error(() -> handleMissingBody(bodyParam)));
				}
				if (hints != null) {
					mono = mono.doOnNext(target ->
							validate(target, hints, bodyParam, bindingContext, exchange));
				}
				return (adapter != null ? Mono.just(adapter.fromPublisher(mono)) : Mono.from(mono));
			}
		}
	}

	// No compatible reader but body may be empty..

	HttpMethod method = request.getMethod();
	if (contentType == null && method != null && SUPPORTED_METHODS.contains(method)) {
		Flux<DataBuffer> body = request.getBody().doOnNext(buffer -> {
			DataBufferUtils.release(buffer);
			// Body not empty, back to 415..
			throw new UnsupportedMediaTypeStatusException(mediaType, this.supportedMediaTypes, elementType);
		});
		if (isBodyRequired) {
			body = body.switchIfEmpty(Mono.error(() -> handleMissingBody(bodyParam)));
		}
		return (adapter != null ? Mono.just(adapter.fromPublisher(body)) : Mono.from(body));
	}

	return Mono.error(new UnsupportedMediaTypeStatusException(mediaType, this.supportedMediaTypes, elementType));
}
Example 11
Source File: AbstractMessageReaderArgumentResolver.java    From java-technology-stack with MIT License 4 votes vote down vote up 
/**
 * Read the body from a method argument with {@link HttpMessageReader}.
 * @param bodyParam represents the element type for the body
 * @param actualParam the actual method argument type; possibly different
 * from {@code bodyParam}, e.g. for an {@code HttpEntity} argument
 * @param isBodyRequired true if the body is required
 * @param bindingContext the binding context to use
 * @param exchange the current exchange
 * @return a Mono with the value to use for the method argument
 * @since 5.0.2
 */
protected Mono<Object> readBody(MethodParameter bodyParam, @Nullable MethodParameter actualParam,
		boolean isBodyRequired, BindingContext bindingContext, ServerWebExchange exchange) {

	ResolvableType bodyType = ResolvableType.forMethodParameter(bodyParam);
	ResolvableType actualType = (actualParam != null ? ResolvableType.forMethodParameter(actualParam) : bodyType);
	Class<?> resolvedType = bodyType.resolve();
	ReactiveAdapter adapter = (resolvedType != null ? getAdapterRegistry().getAdapter(resolvedType) : null);
	ResolvableType elementType = (adapter != null ? bodyType.getGeneric() : bodyType);
	isBodyRequired = isBodyRequired || (adapter != null && !adapter.supportsEmpty());

	ServerHttpRequest request = exchange.getRequest();
	ServerHttpResponse response = exchange.getResponse();

	MediaType contentType = request.getHeaders().getContentType();
	MediaType mediaType = (contentType != null ? contentType : MediaType.APPLICATION_OCTET_STREAM);
	Object[] hints = extractValidationHints(bodyParam);

	if (logger.isDebugEnabled()) {
		logger.debug(exchange.getLogPrefix() + (contentType != null ?
				"Content-Type:" + contentType :
				"No Content-Type, using " + MediaType.APPLICATION_OCTET_STREAM));
	}

	for (HttpMessageReader<?> reader : getMessageReaders()) {
		if (reader.canRead(elementType, mediaType)) {
			Map<String, Object> readHints = Hints.from(Hints.LOG_PREFIX_HINT, exchange.getLogPrefix());
			if (adapter != null && adapter.isMultiValue()) {
				if (logger.isDebugEnabled()) {
					logger.debug(exchange.getLogPrefix() + "0..N [" + elementType + "]");
				}
				Flux<?> flux = reader.read(actualType, elementType, request, response, readHints);
				flux = flux.onErrorResume(ex -> Flux.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					flux = flux.switchIfEmpty(Flux.error(() -> handleMissingBody(bodyParam)));
				}
				if (hints != null) {
					flux = flux.doOnNext(target ->
							validate(target, hints, bodyParam, bindingContext, exchange));
				}
				return Mono.just(adapter.fromPublisher(flux));
			}
			else {
				// Single-value (with or without reactive type wrapper)
				if (logger.isDebugEnabled()) {
					logger.debug(exchange.getLogPrefix() + "0..1 [" + elementType + "]");
				}
				Mono<?> mono = reader.readMono(actualType, elementType, request, response, readHints);
				mono = mono.onErrorResume(ex -> Mono.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					mono = mono.switchIfEmpty(Mono.error(() -> handleMissingBody(bodyParam)));
				}
				if (hints != null) {
					mono = mono.doOnNext(target ->
							validate(target, hints, bodyParam, bindingContext, exchange));
				}
				return (adapter != null ? Mono.just(adapter.fromPublisher(mono)) : Mono.from(mono));
			}
		}
	}

	// No compatible reader but body may be empty..

	HttpMethod method = request.getMethod();
	if (contentType == null && method != null && SUPPORTED_METHODS.contains(method)) {
		Flux<DataBuffer> body = request.getBody().doOnNext(o -> {
			// Body not empty, back to 415..
			throw new UnsupportedMediaTypeStatusException(mediaType, this.supportedMediaTypes, elementType);
		});
		if (isBodyRequired) {
			body = body.switchIfEmpty(Mono.error(() -> handleMissingBody(bodyParam)));
		}
		return (adapter != null ? Mono.just(adapter.fromPublisher(body)) : Mono.from(body));
	}

	return Mono.error(new UnsupportedMediaTypeStatusException(mediaType, this.supportedMediaTypes, elementType));
}
Example 12
Source File: RequestProcessor.java    From spring-cloud-function with Apache License 2.0 4 votes vote down vote up 
private Publisher<?> body(Object handler, ServerWebExchange exchange) {
	ResolvableType elementType = ResolvableType
			.forClass(this.inspector.getInputType(handler));

	// we effectively delegate type conversion to FunctionCatalog
	elementType = ResolvableType.forClass(String.class);

	ResolvableType actualType = elementType;

	Class<?> resolvedType = elementType.resolve();
	ReactiveAdapter adapter = (resolvedType != null
			? getAdapterRegistry().getAdapter(resolvedType) : null);

	ServerHttpRequest request = exchange.getRequest();
	ServerHttpResponse response = exchange.getResponse();

	MediaType contentType = request.getHeaders().getContentType();
	MediaType mediaType = (contentType != null ? contentType
			: MediaType.APPLICATION_OCTET_STREAM);

	if (logger.isDebugEnabled()) {
		logger.debug(exchange.getLogPrefix() + (contentType != null
				? "Content-Type:" + contentType
				: "No Content-Type, using " + MediaType.APPLICATION_OCTET_STREAM));
	}
	boolean isBodyRequired = (adapter != null && !adapter.supportsEmpty());

	MethodParameter bodyParam = new MethodParameter(handlerMethod(handler), 0);
	for (HttpMessageReader<?> reader : getMessageReaders()) {
		if (reader.canRead(elementType, mediaType)) {
			Map<String, Object> readHints = Hints.from(Hints.LOG_PREFIX_HINT,
					exchange.getLogPrefix());
			if (adapter != null && adapter.isMultiValue()) {
				if (logger.isDebugEnabled()) {
					logger.debug(
							exchange.getLogPrefix() + "0..N [" + elementType + "]");
				}
				Flux<?> flux = reader.read(actualType, elementType, request, response,
						readHints);
				flux = flux.onErrorResume(
						ex -> Flux.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					flux = flux.switchIfEmpty(
							Flux.error(() -> handleMissingBody(bodyParam)));
				}
				return Mono.just(adapter.fromPublisher(flux));
			}
			else {
				// Single-value (with or without reactive type wrapper)
				if (logger.isDebugEnabled()) {
					logger.debug(exchange.getLogPrefix() + "0..1 [" + elementType + "]");
				}
				Mono<?> mono = reader.readMono(actualType, elementType, request,
						response, readHints).doOnNext(v -> {
							if (logger.isDebugEnabled()) {
								logger.debug("received: " + v);
							}
						});
				mono = mono.onErrorResume(
						ex -> Mono.error(handleReadError(bodyParam, ex)));
				if (isBodyRequired) {
					mono = mono.switchIfEmpty(
							Mono.error(() -> handleMissingBody(bodyParam)));
				}
				return (adapter != null ? Mono.just(adapter.fromPublisher(mono))
						: Mono.from(mono));
			}
		}
	}

	return Mono.error(new UnsupportedMediaTypeStatusException(mediaType,
			Arrays.asList(MediaType.APPLICATION_JSON), elementType));
}