Develop Reference

Access response status code for successful requests using Spring WebClient

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();
});

Filtering response using webclient

I'm new using webclient to cosume a Rest API and I want to know how can I filter a response to match only what I want.
So I have this endpoint which brings me a customerById but I need to show only the the systemsId = 100
Let me show:
#GetMapping("/getCucoId/{cucoId}")
public Mono<CuCoPerson> getCucoRelationById(#PathVariable Integer cucoId) {
WebClient webClient = WebClient.create();
return webClient.get()
.uri(GET_RELATION_BY_ID + cucoId)
.header("Accept", "application/json")
.header("Authorization", "Bearer eyJraWQiOi.....")
.retrieve()
.bodyToMono(CuCoPerson.class);
}
And the POJO:
#Data
#NoArgsConstructor
#AllArgsConstructor
public class CuCoPerson {
private Integer cucoID;
private List<CustomerRelation> relatedCustomers;
}
And this is the response in Postman:
{
"cucoID": 100288298,
"relatedCustomers": [
{
"customerId": "F6305957",
"systemId": 100
},
{
"customerId": "F8364917",
"systemId": 400
},
{
"customerId": "F4194868",
"systemId": 101
}
]
}
So I need only to show the relatedCustomers who only have a systemID = 100
Thanks in advance!

I think you are looking for either Mono.map(), or Mono.flatMap().
Remove the customers, who don't match in the function, and return the changed object.
#GetMapping("/getCucoId/{cucoId}")
public Mono<CuCoPerson> getCucoRelationById(#PathVariable Integer cucoId) {
WebClient webClient = WebClient.create();
return webClient.get()
.uri(GET_RELATION_BY_ID + cucoId)
.header("Accept", "application/json")
.header("Authorization", "Bearer eyJraWQiOi.....")
.retrieve()
.bodyToMono(CuCoPerson.class)
.map(cuCoPerson -> {
List<CustomerRelation> matches = cuCoPerson.getRelatedCustomers()
.stream()
.filter(relation -> relation.getSystemId().equals(100))
.collect(Collectors.toList());
cuCoPerson.setRelatedCustomers(matches);
return cuCoPerson;
});
}
As mentioned in other answers, doing this kind of filtering on client side is bad practice. If possible the API should expose parameter for systemId and return only the data you need.

First of all this is bad Backend design. Since you (client side) have the need for such info you should have an endpoint available to get your info by customer ID and System ID. Data filtering should be done on the backend and the client should remain as thin as possible. Otherwise you perform logic both on server-side and client-side plus you send some completely unneeded info over the network and then filter it out on the client side. But if that's your available resources and you can't change the server-side then you you take your JSON response, and parse it into your class that maps to that JSON or just into Map<String,Object> if you don't have the class for that JSON and filter it out yourself. To parse a json string to map or a specific POJO you can use Jackson library - method readValue() of ObjectMapper Or Gson library. Also, I wrote my own simple wrapper over Jackson library that simplifies the use. Class JsonUtils is available as part of MgntUtils library (written and maintained by me). This class just has the methods that allow you to parse and de-serialize from/to Json String from/to a class instance. Here is a simple example on how to parse your JSON string into a Map<String,Object> with JSONUtils class
Map<String,Object> myMap
try {
myMap = JsonUtils.readObjectFromJsonString(myJsonStr, Map.class);
} catch(IOException ioe) {
....
}
MgntUtils library available as Maven artifact and on Github (including source code and Javadoc)

it could be something like this:
return webClient.get()
.uri("/someUrl")
.header("Accept", "application/json")
.header("Authorization", "Bearer eyJraWQiOi.....")
.retrieve()
.bodyToFlux(CuCoPerson.class)
.filter(cuCoPerson -> cuCoPerson.getRelatedCustomers().stream().anyMatch(cr -> cr.getSystemId() == 100))
.take(1)
.next();
But this has disadvantage that you are filtering the results on client side (your application). I would try to ask the api provider if s/he is able to provide filter parameter (something like systemId) and in that case you would call the endpoint with that query param.

How to convert Spring WebClient Response to ResponseEntity?

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.

Using BodyInserters to pass parameter with webClient

There is my code.
public Mono<RespDto> function(TransReqDto1 reqDto1, TransReqDto2 reqDto2, String token) {
MultipartBodyBuilder builder = new MultipartBodyBuilder();
builder.part("TransReqDto1", reqDto1);
builder.part("TransReqDto2", reqDto2);
MultiValueMap<String, HttpEntity<?>> parts = builder.build();
LinkedMultiValueMap map = new LinkedMultiValueMap();
map.add("TransReqDto1", reqDto1);
map.add("TransReqDto2", reqDto2);
return
client.post()
.uri("/api")
.body(BodyInserters.fromValue(reqDto1))
.headers(h -> h.setBearerAuth(token.split(" ")[1]))
.retrieve()
.bodyToMono(RespDto.class);
}
My probelm is that I need to send both reqDto1 & reqDto2. I've successfully sent reqDto1 with the code above but I can't figure out a way to send two objects.
Tried MultipartBodybuild and MultiValueMap but both are returning error from the target API. Please give me some hints!! Thank you
Here is the API I am trying to call!
#PostMapping("")
#ApiOperation(value = "test", notes = "test")
public Mono<?> transPost(#Valid #RequestBody TransReqDto1 reqDto1,
#Valid #RequestBody TransReqDto2 reqDto2) {
return testService.function(reqDto1, reqDto2);
}

You cannot use two #RequestBody. It can bind to a single object only. The expected way to do that is to create a wrapper DTO containing all the relevant data:
public class TransReqDto {
private TransReqDto1 transReqDto1;
private TransReqDto2 transReqDto2;
//...
}

Add AWS Signature Header to all rest assured requests

I'm trying to call an get api which is hosted in aws api gateway via rest-assured
I'm able to sign the request and make a call. But to sign the request, I need to pass the full url to AWS to generate the Authorization Header.
For Ex. If I'm going to access an an endpoint
https://my-aws-api.com/basepath/v1/request/123
I need to sign the request via AWSSigner which needs the full endpoint to do so.
My current approach
String baseURI="https://my-aws-api.com";
String basePath="basepath/v1";
String requestPath="request/123";
String endpoint=baseURI+"/"+basePath+"/"+requestPath;
Map<String,String> signedHeaders= aws4sign(endpoint,defaultHeaders);
given()
.log().ifValidationFails()
.headers(signedHeaders)
.when()
.get(endpoint)
.then()
.log().ifValidationFails()
.statusCode(200);
If I do that , then I cant use RestAssured's baseURI, basePath and path params
I want to access it like
RestAssured.baseURI="https://my-aws-api.com";
RestAssured.basePath="basepath/v1";
given()
.log().ifValidationFails()
.pathParam("reqID", "123")
.when()
.get("request/{reqID}")
.then()
.log().ifValidationFails()
.statusCode(200);
AwsSigner
public static Map<String, String> aws4Sign(String endpoint, Map<String, String> headers) throws URISyntaxException {
String serviceName = "execute-api";
AWS4Signer aws4Signer = new AWS4Signer();
aws4Signer.setRegionName(EU_WEST_1.getName());
aws4Signer.setServiceName(serviceName);
DefaultRequest defaultRequest = new DefaultRequest(serviceName);
URI uri = new URI(endpoint);
defaultRequest.setEndpoint(new URI(uri.getScheme(), null, uri.getHost(), uri.getPort(), "", "", ""));
defaultRequest.setHttpMethod(HttpMethodName.GET);
defaultRequest.setResourcePath(uri.getRawPath());
defaultRequest.setHeaders(headers);
aws4Signer.sign(defaultRequest, DefaultAWSCredentialsProviderChain.getInstance().getCredentials());
return defaultRequest.getHeaders();
}
So My question is there any way, I can intercept the RestAssured's request before it makes the call, so that I can get the fully generated end point and add the aws signed header to the call.

I am not familiar with this library but from briefly reading its documentation and Javadoc, you should be able to use a RequestFilter to inspect and alter a request before it is sent out.
Take a look at the Filter section of the user guide.

Thanks to #Ashaman.
The Filter Section is what I'm looking for
You can get the uri and other headers that were passed with requests from RequestSpec and then send it to the function to sign them and remove the old headers and put the new headers. Then forward the request
#BeforeAll
public void init() {
RestAssured.baseURI = "https://my-aws-api.com";
RestAssured.filters((requestSpec, responseSpec, ctx) -> {
Map<String, String> headers = requestSpec.getHeaders()
.asList()
.stream()
.collect(Collectors.toMap(Header::getName, Header::getValue));
Map<String, String> signedHeaders = aws4sign(requestSpec.getURI(), headers);
requestSpec.removeHeaders();
requestSpec.headers(signedHeaders);
return ctx.next(requestSpec, responseSpec);
});
}
And for the tests I can use the features of Rest Assured normally
given()
.log().ifValidationFails()
.pathParam("reqID", "123")
.when()
.get("request/{reqID}")
.then()
.log().ifValidationFails()
.statusCode(200);