We Keep Coding

Throws java.lang.IllegalStateException: block()/blockFirst()/blockLast() when retrying invalid token

I am trying to update the token when I get a response with 401 status code.
In order to do that, I used web client. I know that this mainly used to do reactive development but since resttemplate will soon be deprecated I went for this option.
The issue I am facing is that when it does call the api endpoint to get the new token, it throws a 'java.lang.IllegalStateException: block()/blockFirst()/blockLast() '. And make sense as it stated in the exception message It is not supported in thread reactor-http-nio-3.
I saw that there is a map and flatmap option, but I couldn't figure out how to use it inside the doBeforeRetry() to make it process in a different stream.
I need to have that new token before retrying.
So the question is : How can I get the token via another call and then still do the retry ?
I was able to make it work by using a try catch but I would like to find the solution how to use it inside that retry method.
I also try to block the token request by replacing the token response by a Mono and block it by using myMono.toFuture().get() as stated here block()/blockFirst()/blockLast() are blocking error when calling bodyToMono AFTER exchange()
Here is the code :
Method responsible for the call :
public String getValueFromApi(HashMap<String, Object> filter) {
String response = "";
response = webclient
.post()
.uri(endpoint)
.header("token", token.getToken())
.bodyValue(filter)
.retrieve()
.bodyToMono(String.class)
.retryWhen(Retry.max(3).doBeforeRetry(
retrySignal -> tokenService.getTokenFromApi(env)
).filter(InvalidTokenException.class::isInstance))
.block();
return response;
}
Method that retrieve the token :
public void getTokenFromApi(Environment env) {
HashMap<String, String> requestBody = new HashMap<>();
requestBody.put("name", "name");
requestBody.put("password", "password");
String response = WebClient
.builder()
.baseUrl(BASE_PATH)
.defaultHeader(HttpHeaders.CONTENT_TYPE, "application/json")
.build()
.post()
.uri(tokenUri)
.body(BodyInserters.fromValue(requestBody))
.retrieve()
.bodyToMono(String.class)
.block();
getTokenFromResponse(response);
}
private void getTokenFromResponse(String reponse) {
JsonObject tokenObject = new Gson().fromJson(reponse, JsonObject.class);
setToken(tokenObject.get("token").getAsString());
}
WebClient Builder :
#Bean
public WebClient webClientForApi(WebClient.Builder webClientBuilder) {
return webClientBuilder
.clientConnector(new ReactorClientHttpConnector(httpClient))
.filter(errorHandler())
.filter(logRequest())
.clone()
.baseUrl(BASE_PATH)
.defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
.defaultHeader(HttpHeaders.ACCEPT, "application/json")
.build();
}
public ExchangeFilterFunction errorHandler() {
return ExchangeFilterFunction.ofResponseProcessor(clientResponse -> {
if (clientResponse.statusCode().equals(HttpStatus.UNAUTHORIZED)) {
return Mono.error(InvalidTokenException::new);
} else if (clientResponse.statusCode() == HttpStatus.INTERNAL_SERVER_ERROR) {
return Mono.error(ApiInternalServerException::new);
} else {
return Mono.just(clientResponse);
}
});
}
private ExchangeFilterFunction logRequest() {
return ExchangeFilterFunction.ofRequestProcessor(clientRequest -> {
logger.info("Request: {} {}", clientRequest.method(), clientRequest.url());
clientRequest.headers().forEach((name, values) -> values.forEach(value -> logger.info("{}={}", name, value)));
return Mono.just(clientRequest);
});
}

Java Supplier<> get origins information

I Use the Supplier in my code to call restTemplate and make the custom Message when have exception..
But, im my message, i need get information by my requestCall, But when i cast the request the java thow error
...
My code:
public void execute() {
HttpHeaders headers = buildDefaultHeaders();
UriBuilder uri = UriBuilder.fromUri(wdd3dGatewayEndpoint + API_URL);
HttpEntity request = new HttpEntity(headers);
this.executeRequest(() -> restTemplate.exchange(uri.build(), HttpMethod.DELETE, request, Void.class));
}
My Supplier
protected ResponseEntity executeRequest(Supplier<ResponseEntity> request) {
try {
ResponseEntity response = request.get();
updateSessionToken(response);
return response;
} catch (HttpClientErrorException | HttpServerErrorException e) {
String msg = "WDD3D-Error in service communication<br>" + e.getResponseBodyAsString();
throw new MaestroException(msg);
}
}
Now, i try cast to get URL...
protected ResponseEntity executeRequest(Supplier<ResponseEntity> request) {
try {
ResponseEntity response = request.get();
updateSessionToken(response);
return response;
} catch (HttpClientErrorException | HttpServerErrorException e) {
//THROW EXEPTION HERE... PLEASE HELP...
RequestEntity requestEntity = (RequestEntity) request;
String url = requestEntity.getUrl().toString();
String msg = "WDD3D-Error in service communication<br>" + e.getResponseBodyAsString();
throw new MaestroException(msg);
}
}]

You should use the get() method of the Supplier, see more in the docs.

RequestEntity requestEntity = (RequestEntity) request;
You are trying to cast a Supplier<ResponseEntity> to a RequestEntity.
These are two very different classes and such a cast will never work.
Maybe you want to call request.get() and get the URL from the ResponseEntity that you have.
Tell me if it works for you in the comments or we need to debug further ?

The only thing you are trying to get from the RequestEntity is the URL, which you can't get from the Supplier<ResponseEntity> since it is not a RequestEntity, so why not just pass the URL as another parameter to executeRequest? Then it would have the additional information it needs to log the error.

Response status code showing 200 for gateway error (504)

I have a REST endpoint which call another API which take a while to process and returning 504 error when I verify through Rest client (Insomnia). But in my service I see this transaction as success 200 not 504.
Below is how my code snippet:
public ResponseEntity<Customer> processResponse(Customer customer, String restUri) {
ResponseEntity<Customer> response;
String customerJson = null;
try {
RestTemplate restTemplate = restTemplateBuilder.basicAuthorization(userName, password).build();
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
headers.setContentType(MediaType.APPLICATION_JSON);
HttpEntity<Customer> entity = new HttpEntity<>(customer, headers);
CustomerJson = jacksonUtil.toJSON(customer);
response = restTemplate.exchange(restUri, HttpMethod.PUT, entity, Customer.class);
if (response.getStatusCode().is2xxSuccessful()) {
logger.info("Return success from the server");
} else {
logger.error("Error while getting the response from the server");
}
} catch (Exception ex) {
ex.printStackTrace();
throw ex;
}
return response;
}
What am I missing here? Why its not executing the else block?
Thanks in advance.

Your method seems to be returning null response in case of error. Can you check if you have done any handling in caller and passing 200 from controller layer itself.

How do I log out the body of a failed response to a Spring WebFlux WebClient request while returning the response to the caller?

I'm very new to reactive programming and I have a REST service that takes a request and then calls to another API using the WebFlux WebClient. When the API responds with a 4xx or 5xx response, I want to log the response body in my service, and then pass on the response to the caller. I've found a number of ways to handle logging the response, but they generally return Mono.error to the caller, which is not what I want to do. I have this almost working, but when I make the request to my service, while I get back the 4xx code that the API returned, my client just hangs waiting for the body of the response, and the service never seems to complete processing the stream. I'm using Spring Boot version 2.2.4.RELEASE.
Here's what I've got:
Controller:
#PostMapping(path = "create-order")
public Mono<ResponseEntity<OrderResponse>> createOrder(#Valid #RequestBody CreateOrderRequest createOrderRequest) {
return orderService.createOrder(createOrderRequest);
}
Service:
public Mono<ResponseEntity<OrderResponse>> createOrder(CreateOrderRequest createOrderRequest) {
return this.webClient
.mutate()
.filter(OrderService.errorHandlingFilter(ORDERS_URI, createOrderRequest))
.build()
.post()
.uri(ORDERS_URI)
.contentType(MediaType.APPLICATION_JSON)
.bodyValue(createOrderRequest)
.exchange()
.flatMap(response -> response.toEntity(OrderResponse.class));
}
public static ExchangeFilterFunction errorHandlingFilter(String uri, CreateOrderRequest request) {
return ExchangeFilterFunction.ofResponseProcessor(clientResponse -> {
if (clientResponse.statusCode() != null && (clientResponse.statusCode().is5xxServerError() || clientResponse.statusCode().is4xxClientError())) {
return clientResponse.bodyToMono(String.class)
.flatMap(errorBody -> OrderService.logResponseError(clientResponse, uri, request, errorBody));
} else {
return Mono.just(clientResponse);
}
});
}
static Mono<ClientResponse> logResponseError(ClientResponse response, String attemptedUri, CreateOrderRequest orderRequest, String responseBody) {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
try {
log.error("Response code {} received when attempting to hit {}, request:{}, response:{}",
response.rawStatusCode(), attemptedUri, objectMapper.writeValueAsString(orderRequest),
responseBody);
} catch (JsonProcessingException e) {
log.error("Error attempting to serialize request object when reporting on error for request to {}, with code:{} and response:{}",
attemptedUri, response.rawStatusCode(), responseBody);
}
return Mono.just(response);
}
As you can see, I'm simply trying to return a Mono of the original response from the logResponseError method. For my testing, I'm submitting a body with a bad element which results in a 422 Unprocessable Entity response from the ORDERS_URI endpoint in the API I'm calling. But for some reason, while the client that called the create-order endpoint receives the 422, it never receives the body. If I change the return in the logResponseError method to be
return Mono.error(new Exception("Some error"));
I receive a 500 at the client, and the request completes. If anyone knows why it won't complete when I try to send back the response itself, I would love to know what I'm doing wrong.

Can't have your cake and eat it too!
The issue here is that you are trying to consume the body of the response twice, which is not allowed. Normally you would get an error for doing so.
Once in
return clientResponse.bodyToMono(String.class)
but also in
response.toEntity(OrderResponse.class)
which actually runs
#Override
public <T> Mono<ResponseEntity<T>> toEntity(Class<T> bodyType) {
return WebClientUtils.toEntity(this, bodyToMono(bodyType));
}
So one solution would be to process the ResponseEntity instead of the ClientResponse as follows since you don't actually want to do any reactive stuff with the body
public Mono<ResponseEntity<OrderResponse>> createOrder(CreateOrderRequest createOrderRequest) {
return this.webClient
//no need for mutate unless you already have things specified in
//base webclient?
.post()
.uri(ORDERS_URI)
.contentType(MediaType.APPLICATION_JSON)
.bodyValue(createOrderRequest)
.exchange()
//Here you map the response to an entity first
.flatMap(response -> response.toEntity(OrderResponse.class))
//Then run the errorHandler to do whatever
//Use doOnNext since there isn't any reason to return anything
.doOnNext(response ->
errorHandler(ORDERS_URI,createOrderRequest,response));
}
//Void doesn't need to return
public static void errorHandler(String uri, CreateOrderRequest request,ResponseEntity<?> response) {
if( response.getStatusCode().is5xxServerError()
|| response.getStatusCode().is4xxClientError())
//run log method if 500 or 400
OrderService.logResponseError(response, uri, request);
}
//No need for redundant final param as already in response
static void logResponseError(ResponseEntity<?> response, String attemptedUri, CreateOrderRequest orderRequest) {
//Do the log stuff
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
try {
log.error("Response code {} received when attempting to hit {}, request:{}, response:{}",
response.getStatusCodeValue(), attemptedUri, objectMapper.writeValueAsString(orderRequest),
response.getBody());
} catch (JsonProcessingException e) {
log.error("Error attempting to serialize request object when reporting on error for request to {}, with code:{} and response:{}",
attemptedUri, response.getStatusCodeValue(), response.getBody());
}
}
Note that there isn't really a reason to use the ExchangeFilter since you aren't actually doing any filtering, just performing an action based off the response

Spring OAuth2 Rest exception swallows HttpResponse code

Restservice I am invoking using oauth2resttemplate returns a response with status code 403. I see that in my ClientHttpRequestInterceptor log lines injected to the resttemplate.
This is the interceptor to intercept request and response. traceResponse() logs response status code as 403 which I expected.
public class RequestInterceptor implements ClientHttpRequestInterceptor {
#Override
public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
try
{
traceRequest(request, body);
} catch (Exception e)
{
ManagerLog.alertLog("Exception occurred", e);
}
ClientHttpResponse response = execution.execute(request, body);
traceResponse(response);
return response;
}
private void traceRequest(HttpRequest request, byte[] body) throws Exception {
ManagerLog.infoLog("===========================request begin================================================");
ManagerLog.infoLog("URI : "+request.getURI());
ManagerLog.infoLog("Method : "+request.getMethod());
ManagerLog.infoLog("Headers : "+request.getHeaders() );
ManagerLog.infoLog("Request body : "+new String(body, "UTF-8"));
ManagerLog.infoLog("==========================request end================================================");
}
private void traceResponse(ClientHttpResponse response) throws IOException {
ManagerLog.infoLog("============================response begin==========================================");
ManagerLog.infoLog("Response Status code : "+ response.getStatusCode());
ManagerLog.infoLog("Response Status text : "+ response.getStatusText());
ManagerLog.infoLog("Response Headers : "+ response.getHeaders());
// ManagerLog.infoLog("Response body : "+ StreamUtils.copyToString(response.getBody(), Charset.defaultCharset()));
ManagerLog.infoLog("=======================response end=================================================");
}
}
But down here I see 400 instead of 403. But I see in the spring source code it is actually hardcoded to 400 in parent class(OAuth2Exception.java) of InvalidGrantException.
try{
objectResponseEntity = oauth2RestTemplate.exchange(url, httpMethod, httpEntity, pojo) -- throws an InvalidGrantException
} catch (HttpStatusCodeException e)
{
...
} catch(InvalidGrantException e)
{
errorCode = e.getHttpErrorCode(); -- was expecting 403 but returning 400
...
}
Any idea on how to get the actual http response code from the exception?