I'm able to return ResponseEntity using toEntity() method like below:
#GetMapping("/uri")
public Mono<ResponseEntity<Data[]>> methodName() {
return webClient
.get()
.uri("http://localhost:8088/externalService")
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.toEntity(Data[].class);
}
But I want to process response headers before returning.
The above code converts WebClient response to ResponseEntity and returns immediately but I want to store it in a ResponseEntity variable, process it, and then return the ResponseEntity back.
I referred this -> Spring WebClient Documentation
WHen I tried to store it in a varibale, I get this error -> "block()/blockFirst()/blockLast() are blocking, which is not supported in thread reactor-http-nio-3"
You can simply use the Reactor's map operator to modify the headers:
return webClient
.get()
.uri("http://localhost:8088/externalService")
.accept(MediaType.APPLICATION_JSON)
.retrieve()
.toEntity(Data[].class)
.map(responseEntity -> responseEntity.getHeaders().add("header", "header-value");
Alternatively, you can use .handle operator in order to provide response processing:
.handle((responseEntity, sink) -> {
if(!isValid(responseEntity)){
sink.error(new InvalidResponseException());
} else if (isOk(responseEntity))
sink.next(responseEntity);
}
else {
//just ignore element
}
})
Spring Starter Web dependency was missing in my pom.xml. Found it and added it back.
Now able to get WebClient response in ResponseEntity format.
Related
I'm trying to call an api with 2 call using webclient.
The first call return a token.
The second call use the token.
public Mono<GetToken> getToken{
return webClient
.get()
.uri(uriBuilder ->
uriBuilder
.path("api/getToken")
.build()
)
.retrieve()
.bodyToMono(Object.class);
}
public Mono<GetToken> getData{
return webClient
.get()
.uri(uriBuilder ->
uriBuilder
.path("api/getData/"+tokenID)
.build()
)
.retrieve()
.bodyToMono(Object2.class);
}
How can I use the data from the first request in the second without using the block() function
Use Mono#flatMap.
Mono<Object2> res = getToken().flatMap(token -> getData(token));
I have created below webclient and using it inside of my service to make HTTP third party calls.
#Configuration
public class WebclientConfig {
#Bean
public WebClient webClient() {
// custom client connector with connection pool disabled is being used as by default the connection pooling is done and connection reset happens after some idle time.
return WebClient.builder()
.clientConnector(new ReactorClientHttpConnector(HttpClient.newConnection()))
.defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
.defaultHeader(HttpHeaders.ACCEPT, MediaType.APPLICATION_JSON_VALUE)
.build();
}
}
and in my service, I am calling the third party service like below.
private Flux<BusinessObject> getBusinessObjects(String serviceURL) {
return this.webClient.get()
.uri(serviceURL)
.retrieve()
.bodyToFlux(BusinessObject.class) //code below this, do I have to copy for each webclient request to configure the retry, even if the values are same
.retryWhen(Retry.backoff(3, Duration.of(2, ChronoUnit.SECONDS))
.doBeforeRetry((value) -> log.info("Retrying request " + value))
.filter(error -> error instanceof WebClientRequestException)
.onRetryExhaustedThrow((retryBackoffSpec, retrySignal) ->
new RuntimeException(retrySignal.failure().getMessage())));
}
My question is as in comment in above code.
I have multiple webclient calls, but I want to configure the retry backoff configuration at a single place. How can I do that? so that my code should look like below
private Flux<BusinessObject> getBusinessObjects(String serviceURL) {
return this.webClient.get()
.uri(serviceURL)
.retrieve()
.bodyToFlux(BusinessObject.class)
.somCommonRetryCodeWrappingTheRetryLogic();
}
You can use transform operator for this purpose:
private Flux<BusinessObject> getBusinessObjects(String serviceURL) {
return this.webClient.get()
.uri(serviceURL)
.retrieve()
.bodyToFlux(BusinessObject.class)
.transform(originalFlux -> wrapWithRetry(originalFlux));
}
private <T> Flux<T> wrapWithRetry(Flux<T> originalFlux) {
return originalFlux
.retryWhen(Retry.backoff(3, Duration.of(2, ChronoUnit.SECONDS))
.doBeforeRetry((value) -> log.info("Retrying request " + value))
.filter(error -> error instanceof WebClientRequestException)
.onRetryExhaustedThrow((retryBackoffSpec, retrySignal) ->
new RuntimeException(retrySignal.failure().getMessage())));
}
Only drawback is that if you have Mono use cases as well then you need to implement it twice.
If that is still too much copy-paste, you can consider defining an ExchangeFilterFunction to apply retry for every WebClient call automatically. Something like this:
WebClient.builder()
// ...
.filter((request, next) -> next.exchange(request).retry()) // add full retry config here
.build();
I need to be able to access the status code of a request. The call can be successful in either of two ways 200 or 201. This is obvious when calling via postman but using the web client, so far I haven't been able to determine which has occurred.
webClient.post()
.uri(url)
.header(HttpHeaders.ACCEPT, MediaType.ALL_VALUE)
.header(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
.header(HttpHeaders.AUTHORIZATION, bearerToken)
.bodyValue(bodyMap)
.retrieve()
.onStatus(
HttpStatus.BAD_REQUEST::equals,
response -> response.bodyToMono(String.class).map(Exception::new))
.bodyToMono(Map.class)
I was thinking maybe I could set an integer variable using within the onStatus() lambda function. Is it even possible to access external variables within a lambda function?
int responseStatus;
// post call
.onStatus(
HttpStatus.CREATED::equals,
response -> ... // do something to set responseStatus
You could use .toEntity(Class<T> bodyClass) method to get entity wrapped in response object ResponseEntity<T>
var response = webClient.post()
.uri(uri)
.retrieve()
.toEntity(Map.class)
.map(res -> {
if (res.getStatusCode().equals(HttpStatus.OK)) {
...
}
return res.getBody();
});
I have a back-end(Springboot) application that is connected to Azure AD and a front-end application that accesses it. In the front-end, I am requiring the user to authenticate using MSAL and passing this authentication to the BE using the On-Behalf-Of flow.
In the front-end, when I am trying to specify the registered client I simple use:
#RegisteredOAuth2AuthorizedClient("back-end") OAuth2AuthorizedClient authorizedClient
I'm trying to create another back-end application that my existing back-end will call and pass the authentication using OBO flow. To check the difference between the initial token from the user and the token the BE will provide to the new BE application, I created a log that fetch the token from these client like authorizedClient.getAccessToken().getTokenValue().
Now that I don't want the explicit approach and want only to add directly in the webclient request the .attributes(clientRegistrationId("new-back-end")), is there any way to check the token? Or at least get the OAuth2AuthorizedClient from the request?
Sample code:
webClient.get()
.uri(new URI(resourceBaseUri + resourceEndpoint))
.attributes(clientRegistrationId("new-be-app"))
.retrieve()
.bodyToMono(String.class)
.block();
• You can do the same as desired by you by using the ‘ServerOAuth2AuthorizedClientExchangeFilterFunction’ to determine the client to use by resolving the ‘OAuth2AuthorizedClient’ from the ‘ClientRequest.attributes()’. The following code shows how to set an ‘OAuth2AuthorizedClient’ as a request attribute: -
#GetMapping("/")
public Mono<String> index(#RegisteredOAuth2AuthorizedClient("okta")
OAuth2AuthorizedClient authorizedClient) {
String resourceUri = ...
return webClient
.get()
.uri(resourceUri)
.attributes(oauth2AuthorizedClient(authorizedClient))
.retrieve()
.bodyToMono(String.class)
...
.thenReturn("index");
}
Note: - ‘oauth2AuthorizedClient()’ is a static method in ‘ServerOAuth2AuthorizedClientExchangeFilterFunction’.
Also, please note that the following code shows how to set the ‘ClientRegistration.getRegistrationId()’ as a request attribute: -
#GetMapping("/")
public Mono<String> index() {
String resourceUri = ...
return webClient
.get()
.uri(resourceUri)
.attributes(clientRegistrationId("okta"))
.retrieve()
.bodyToMono(String.class)
...
.thenReturn("index");
}
You can use the code below also for your purpose: -
#Component
#RequiredArgsConstructor
public class OAuth2Utils {
private final ServerOAuth2AuthorizedClientRepository authorizedClientRepository;
public Mono<OAuth2AuthorizedClient> extractOAuth2AuthorizedClient(ServerRequest request) {
return request.principal()
.filter(principal -> principal instanceof OAuth2AuthenticationToken)
.cast(OAuth2AuthenticationToken.class)
.flatMap(auth -> authorizedClientRepository.loadAuthorizedClient(auth.getAuthorizedClientRegistrationId(), auth, request.exchange()));
}
}
Please find the links below for more information: -
How to access OAuth2AuthorizedClient in Webflux Functional Endpoints?
https://docs.spring.io/spring-security/reference/reactive/oauth2/client/authorized-clients.html#_providing_the_authorized_client
I'm trying to run this code:
Mono<String> personMono = Mono.just("wfw");
WebClient client = WebClient.create("https://webhook.site");
Mono<Void> result = client.post()
.uri("/a6ad3a35-61c6-4bfc-8d8c-7e5a3e2462aa")
.contentType(MediaType.APPLICATION_JSON)
.body(personMono, String.class)
.exchange()
.flatMap(response -> response.bodyToMono(Void.class));
result.subscribe();
But request is not send. Do you know what I need to add in order to make POST request? I can't find what I'm missing?