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

The following examples show how to use reactor.core.publisher.Mono#switchIfEmpty() . These examples are extracted from open source projects. 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 Project: Moss   File: ChainingStrategy.java    License: Apache License 2.0 6 votes vote down vote up
@Override
public Mono<Endpoints> detectEndpoints(Instance instance) {
    Mono<Endpoints> result = Mono.empty();
    for (EndpointDetectionStrategy delegate : delegates) {
        result = result.switchIfEmpty(delegate.detectEndpoints(instance));
    }
    return result.switchIfEmpty(Mono.just(Endpoints.empty()));
}
 
Example 2
@Override
public Mono<ReactiveHttpResponse> executeRequest(ReactiveHttpRequest request) {

  Mono<Object> bodyMono;
  if (request.body() instanceof Mono) {
    bodyMono = ((Mono<Object>) request.body());
  } else if (request.body() instanceof Flux) {
    bodyMono = ((Flux) request.body()).collectList();
  } else {
    bodyMono = Mono.just(request.body());
  }
  bodyMono = bodyMono.switchIfEmpty(Mono.just(new byte[0]));

  return bodyMono.<ReactiveHttpResponse>flatMap(body -> {
    MultiValueMap<String, String> headers = new LinkedMultiValueMap<>(request.headers());
    if (acceptGzip) {
      headers.add("Accept-Encoding", "gzip");
    }

    ResponseEntity response =
            restTemplate.exchange(request.uri().toString(), HttpMethod.valueOf(request.method()),
                    new HttpEntity<>(body, headers), responseType());

    return Mono.just(new FakeReactiveHttpResponse(response, returnPublisherType));
  })
          .onErrorMap(ex -> ex instanceof ResourceAccessException
                              && ex.getCause() instanceof SocketTimeoutException,
                  ReadTimeoutException::new)
          .onErrorResume(HttpStatusCodeException.class,
                  ex -> Mono.just(new ErrorReactiveHttpResponse(ex)));
}
 
Example 3
@Override
public Mono<ReactiveHttpResponse> executeRequest(ReactiveHttpRequest request) {

  Mono<Object> bodyMono;
  if (request.body() instanceof Mono) {
    bodyMono = ((Mono<Object>) request.body());
  } else if (request.body() instanceof Flux) {
    bodyMono = ((Flux) request.body()).collectList();
  } else {
    bodyMono = Mono.just(request.body());
  }
  bodyMono = bodyMono.switchIfEmpty(Mono.just(new byte[0]));

  return bodyMono.<ReactiveHttpResponse>flatMap(body -> {
    MultiValueMap<String, String> headers = new LinkedMultiValueMap<>(request.headers());
    if (acceptGzip) {
      headers.add("Accept-Encoding", "gzip");
    }

    ResponseEntity response =
            restTemplate.exchange(request.uri().toString(), HttpMethod.valueOf(request.method()),
                    new HttpEntity<>(body, headers), responseType());

    return Mono.just(new FakeReactiveHttpResponse(response, returnPublisherType));
  })
          .onErrorMap(ex -> ex instanceof ResourceAccessException
                              && ex.getCause() instanceof SocketTimeoutException,
                  ReadTimeoutException::new)
          .onErrorResume(HttpStatusCodeException.class,
                  ex -> Mono.just(new ErrorReactiveHttpResponse(ex)));
}
 
Example 4
@Override
public Mono<Endpoints> detectEndpoints(Instance instance) {
	Mono<Endpoints> result = Mono.empty();
	for (EndpointDetectionStrategy delegate : delegates) {
		result = result.switchIfEmpty(delegate.detectEndpoints(instance));
	}
	return result.switchIfEmpty(Mono.just(Endpoints.empty()));
}
 
Example 5
private Mono<Object> decodeContent(MethodParameter parameter, Message<?> message,
		boolean isContentRequired, Flux<DataBuffer> content, MimeType mimeType) {

	ResolvableType targetType = ResolvableType.forMethodParameter(parameter);
	Class<?> resolvedType = targetType.resolve();
	ReactiveAdapter adapter = (resolvedType != null ? getAdapterRegistry().getAdapter(resolvedType) : null);
	ResolvableType elementType = (adapter != null ? targetType.getGeneric() : targetType);
	isContentRequired = isContentRequired || (adapter != null && !adapter.supportsEmpty());
	Consumer<Object> validator = getValidator(message, parameter);

	Map<String, Object> hints = Collections.emptyMap();

	for (Decoder<?> decoder : this.decoders) {
		if (decoder.canDecode(elementType, mimeType)) {
			if (adapter != null && adapter.isMultiValue()) {
				Flux<?> flux = content
						.map(buffer -> decoder.decode(buffer, elementType, mimeType, hints))
						.onErrorResume(ex -> Flux.error(handleReadError(parameter, message, ex)));
				if (isContentRequired) {
					flux = flux.switchIfEmpty(Flux.error(() -> handleMissingBody(parameter, message)));
				}
				if (validator != null) {
					flux = flux.doOnNext(validator);
				}
				return Mono.just(adapter.fromPublisher(flux));
			}
			else {
				// Single-value (with or without reactive type wrapper)
				Mono<?> mono = content.next()
						.map(buffer -> decoder.decode(buffer, elementType, mimeType, hints))
						.onErrorResume(ex -> Mono.error(handleReadError(parameter, message, ex)));
				if (isContentRequired) {
					mono = mono.switchIfEmpty(Mono.error(() -> handleMissingBody(parameter, message)));
				}
				if (validator != null) {
					mono = mono.doOnNext(validator);
				}
				return (adapter != null ? Mono.just(adapter.fromPublisher(mono)) : Mono.from(mono));
			}
		}
	}

	return Mono.error(new MethodArgumentResolutionException(
			message, parameter, "Cannot decode to [" + targetType + "]" + message));
}
 
Example 6
/**
 * 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 7
/**
 * 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 8
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));
}