I prefer to use the methods provided by the ClientResponse to handle http errors and throw exceptions: WebClient.create() .post() .uri( url ) .body( bodyObject == null ? null : BodyInserters.fromValue( bodyObject ) ) .accept( MediaType.APPLICATION_JSON ) .headers( headers ) .exchange() .flatMap( clientResponse -> { //Error handling if ( clientResponse.statusCode().isError() ) { // or clientResponse.statusCode().value() >= … Read more
It’s because switchIfEmpty accepts Mono “by value”. Meaning that even before you subscribe to your mono, this alternative mono’s evaluation is already triggered. Imagine a method like this: Mono<String> asyncAlternative() { return Mono.fromFuture(CompletableFuture.supplyAsync(() -> { System.out.println(“Hi there”); return “Alternative”; })); } If you define your code like this: Mono<String> result = Mono.just(“Some payload”).switchIfEmpty(asyncAlternative()); It’ll always … Read more
Annotate your MyControllerTest test class with @AutoConfigureWebTestClient annotation. That should solve the issue.
Two key things here about WebClient: Its HTTP resources (connections, caches, etc) are managed by the underlying library, referenced by the ClientHttpConnector that you can configure on the WebClient WebClient is immutable With that in mind, you should try to reuse the same ClientHttpConnector across your application, because this will share the connection pool – … Read more
This is really not as complicated as other answers imply. The only way to stream the data without buffering it all in memory is to use a pipe, as @jin-kwon suggested. However, it can be done very simply by using Spring’s BodyExtractors and DataBufferUtils utility classes. Example: private InputStream readAsInputStream(String url) throws IOException { PipedOutputStream … Read more
Reactive programming is a programming paradigm, but I wouldn’t call it new. It’s actually been around for a while. Just like object-oriented programming, functional programming, or procedural programming, reactive programming is another programming paradigm. Paradigm is defined by Reactive Manifesto Reactive Streams, on the other hand, is a specification. For Java programmers, Reactive Streams is … Read more
Looks like Spring 5.1.1 (Spring boot 2.1.0) removed HttpClientOptions from ReactorClientHttpConnector, so you can not configure options while creating instance of ReactorClientHttpConnector One option that works now is: val sslContext = SslContextBuilder .forClient() .trustManager(InsecureTrustManagerFactory.INSTANCE) .build() val httpClient = HttpClient.create().secure { t -> t.sslContext(sslContext) } val webClient = WebClient.builder().clientConnector(ReactorClientHttpConnector(httpClient)).build() Basically while creating the HttpClient, we are … Read more
As explained in the Spring Boot reference documentation, Spring Boot will auto-configure a Spring MVC application if both MVC and WebFlux are available. There are several reasons for this: Spring MVC can’t run on Netty both infrastructure will compete for the same job (for example, serving static resources, the mappings, etc) mixing both runtime models … Read more
After the question, the present documentation does provide some clues about the concurrency model and the threads one could expect (but I still think that clearer/better descriptions of what happens under-the-scene from a multi-threading perspective would be highly appreciated by Spring newcomers). It discusses the difference between Spring MVC and Spring WebFlux (1-thread-per-request model vs. … Read more
Backpressure in WebFlux In order to understand how Backpressure works in the current implementation of the WebFlux framework, we have to recap the transport layer used by default here. As we may remember, the normal communication between browser and server (server to server communication usually the same as well) is done through the TCP connection. … Read more