I need to set different HTTP Status code for my REST webservice request.
Basically user will send ISBN number , I need to validate it
if user send empty request body , give error message ISBN cannot be empty
and set http status code
if user gives Alphabets , Given error message Alphabets not allowed and set http status code appropriate
if user gives wrong format, Give error message wrong format and set different HTTP status code.
if isbn is not valid, Give error message Not a Valid ISBN number and set appropriate HTTP status code.
If Valid ISBN number then return book name with http status as 200.
I tried setting http status code but its not reflecting.
#RequestMapping(value = "/person", method = RequestMethod.POST,
consumes = "application/json", produces = "application/json")
public ResponseEntity<StatusBean> findBook(#RequestBody String json) {
StatusBean sb = new StatusBean();
if(json==null) {
sb.setMessage("Request Cannot be Null");
return new ResponseEntity<StatusBean>(sb,HttpStatus.BAD_REQUEST);
}
if(!isNumeric(json)) {
sb.setMessage("Request Cannot have Alphabets Characters");
//here i need to set different status
return new ResponseEntity<StatusBean>(sb,HttpStatus.BAD_REQUEST);
}
if(!isValidFormat(json)) {
sb.setMessage("Request Cannot have Alphabets Characters");
//here i need to set different status
return new ResponseEntity<StatusBean>(sb,HttpStatus.BAD_REQUEST);
}
if(!isValidISBN(json)) {
sb.setMessage("Request Cannot have Alphabets Characters");
//here i need to set different status
return new ResponseEntity<StatusBean>(sb,HttpStatus.BAD_REQUEST);
}
Map<String,String> map = new HashMap<>();
map.put("book", "Effective Java");
sb.setResponseJSONMap(map);
return new ResponseEntity<StatusBean>(sb,HttpStatus.OK);
}
public class StatusBean {
private String message;
private Map<String,String> responseJSONMap;
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public Map<String, String> getResponseJSONMap() {
return responseJSONMap;
}
public void setResponseJSONMap(Map<String, String> responseJSONMap) {
this.responseJSONMap = responseJSONMap;
}
}
One of the most elegant solutions is the following:
You can throw a custom exception in case of a validation error, like this:
#RequestMapping(...)
public ResponseEntity<StatusBean> findBook(#RequestBody String json) throws Exception {
...
if(json==null) {
throw new NullRequestException();
}
if(!isNumeric(json)) {
throw new RequestContainsAlphabetsException();
}
if(!isValidFormat(json)) {
throw new InvalidFormatException();
}
...
}
And then you need to define an own, global exception handler at application level. In this custom exception handler, you will catch the thrown exceptions and send back a proper response to clients with a custom error message, an HTTP response code, a timestamp, etc.
For more details see this page.
#RequestMapping(value = "/person", method = RequestMethod.POST,
consumes = "application/json", produces = "application/json")
public ResponseEntity<StatusBean> findBook(#RequestBody(required=false) String json) {
// rest of the code
}
try using (required=false) with request body. Spring requires resuest body by default.
Related
I have built a web application in Spring Boot that has a form and besides the values from the form that it inserts in the database it takes from the header the username. This is the code from the Controller:
#PostMapping("/BilantErr/")
public String postIndex(#RequestParam(name = "cui") String cui, #RequestParam(name = "an_raportare") String anRaportare,
#RequestParam(name = "perioada") String perioada,
#RequestHeader("iv-user") String operator, #RequestParam(name = "motivatie") String motivatie, Model model) {
String page = "";
//String operator = "serban";
try {
if (repository.insert(cui, anRaportare, operator, motivatie, perioada) == true) {
page = "success";
} else {
page = "error";
}
} catch (Exception e) {
Logger logger = LoggerFactory.getLogger(BilantErr.class);
}
return page;
}
The error that I am getting is : Resolved [org.springframework.web.bind.MissingRequestHeaderException: Required request header 'iv-user' for method parameter type String is not present]
What may be the problem ? There is an application already built in JSF that works and takes the user from the header and I have to replace it with a Spring app. What am I doing wrong ? Thanks
MissingRequestHeaderException means the HTTP request doesn't contain a "iv-user" header. You must have a look to your request first. You can read all headers of the HTTP request by following code snippet:
#GetMapping("/listHeaders")
public ResponseEntity<String> multiValue(
#RequestHeader MultiValueMap<String, String> headers) {
headers.forEach((key, value) -> {
LOG.info(String.format(
"Header '%s' = %s", key, value.stream().collect(Collectors.joining("|"))));
});
return new ResponseEntity<String>(
String.format("Listed %d headers", headers.size()), HttpStatus.OK);
}
The request header "iv-user" is required but does not seem to be present in the request you receive. You could fix your request or make the header optional: #RequestHeader(value = "iv-user", required = false)
I am making rest template call to get the data from other microservice for this I am using the exchange method. This I am doing when a particular function gets called and below is the sample code for the same.
#Service
public void findUserById()
{
String username = "chathuranga";
String password = "123";
Integer userId = 1;
String url = "http://localhost:8080/users/" + userId;
//setting up the HTTP Basic Authentication header value
String authorizationHeader = "Basic " + DatatypeConverter.printBase64Binary((username + ":" + password).getBytes());
HttpHeaders requestHeaders = new HttpHeaders();
//set up HTTP Basic Authentication Header
requestHeaders.add("Authorization", authorizationHeader);
requestHeaders.add("Accept", MediaType.APPLICATION_JSON_VALUE);
//request entity is created with request headers
HttpEntity<AddUserRequest> requestEntity = new HttpEntity<>(requestHeaders);
ResponseEntity<FindUserResponse> responseEntity = restTemplate.exchange(
url,
HttpMethod.GET,
requestEntity,
FindUserResponse.class
);
// if (responseEntity.getStatusCode() == HttpStatus.OK) {
// System.out.println("response received");
System.out.println(responseEntity.getBody());
//} else {
// System.out.println("error occurred");
// System.out.println(responseEntity.getStatusCode());
//}
}
To handle the various exceptions code for example 500, 404 I want to made resttemplate builder class, (not the commented code) Which must be coded in different class for this I am referring this (custom hadler part)
I am not using try catch as it is not good approach when multiple calls happen in production environment.
I am also getting resource access exception while using exchange function which also needs to handle.
Now I am not getting how this class of custom handler should be called for handling response like 500.
If someone can help me with the sample code that would be very helpfull as I cannot test my code because it is not deployed for testing purpose till now
here is a sample
#ControllerAdvice
public class ErrorHandler {
#ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
#ExceptionHandler(ResourceAccessException.class)
public #ResponseBody
String handleResourceAccessException(
ResourceAccessException ex) {
return "internal server error";
}
}
When you use #ControllerAdvice , it will catch the exception you mention in #ExceptionHandler and here you can handle it the way you want.
If you don't want to return the response to the client right away, (for example, ignore ResourceAccessException and continue), you can override the handleError method of DefaultResponseErrorHandler, which is used by RestTemplate to handle the non 2xx codes.
public class ErrorHandler extends DefaultResponseErrorHandler {
#Override
public void handleError(ClientHttpResponse response, HttpStatus statusCode) {
// write your code here
}
}
I have an Microservice and it gets an response from another. And based on the response I get I need to respond accordingly. I have no complete List of Error code I can receive, so the question is - can I generate error codes on the fly for my own response? From what I saw in spring the responses are predefined in code. I need to be flexible.
For example:
I receive a 409 I will respond with 409
I receive a 400 I will respond with 400
I receive a XXX code I will respond with XXX.
Try this code: (Sample code)
#RequestMapping(value = "/validate", method = RequestMethod.GET, produces = "application/json")
public ResponseEntity<ErrorBean> validateUser(#QueryParam("jsonInput") final String jsonInput) {
int numberHTTPDesired = 400;
ErrorBean responseBean = new ErrorBean();
responseBean.setError("ERROR");
responseBean.setMessage("Error in validation!");
return new ResponseEntity<ErrorBean>(responseBean, HttpStatus.valueOf(numberHTTPDesired));
}
I have worked on such a use case using the following concept. Try to create a generic exception across micro services. Take 2 params in the exception as error message and another one as error code. Throw the exception from the service being called and catch the same exception in the calling service in the rest template or feign client call.
public class MyException extends Exception {
private String errorCode;
public MyException() {
super();
}
public MyException(String message, String errorCode) {
super(message);
this.errorCode = errorCode;
}
}
--
try {
return myApiService.getUser();//call to myApiService microservice
} catch (MyException e) {
logger.error("Error: {}", e.getMessage());
throw new MyException(e.getMessage(), e.getCode());
}
I'm using the following exception handler in Spring 4.0.3 to intercept exceptions and display a custom error page to the user:
#ControllerAdvice
public class ExceptionHandlerController
{
#ExceptionHandler(value = Exception.class)
public ModelAndView handleError(HttpServletRequest request, Exception e)
{
ModelAndView mav = new ModelAndView("/errors/500"));
mav.addObject("exception", e);
return mav;
}
}
But now I want a different handling for JSON requests so I get JSON error responses for this kind of requests when an exception occurred. Currently the above code is also triggered by JSON requests (Using an Accept: application/json header) and the JavaScript client doesn't like the HTML response.
How can I handle exceptions differently for HTML and JSON requests?
The ControllerAdvice annotation has an element/attribute called basePackage which can be set to determine which packages it should scan for Controllers and apply the advices. So, what you can do is to separate those Controllers handling normal requests and those handling AJAX requests into different packages then write 2 Exception Handling Controllers with appropriate ControllerAdvice annotations. For example:
#ControllerAdvice("com.acme.webapp.ajaxcontrollers")
public class AjaxExceptionHandlingController {
...
#ControllerAdvice("com.acme.webapp.controllers")
public class ExceptionHandlingController {
The best way to do this (especially in servlet 3) is to register an error page with the container, and use that to call a Spring #Controller. That way you get to handle different response types in a standard Spring MVC way (e.g. using #RequestMapping with produces=... for your machine clients).
I see from your other question that you are using Spring Boot. If you upgrade to a snapshot (1.1 or better in other words) you get this behaviour out of the box (see BasicErrorController). If you want to override it you just need to map the /error path to your own #Controller.
As you have the HttpServletRequest, you should be able to get the request "Accept" header. Then you could process the exception based on it.
Something like:
String header = request.getHeader("Accept");
if(header != null && header.equals("application/json")) {
// Process JSON exception
} else {
ModelAndView mav = new ModelAndView("/errors/500"));
mav.addObject("exception", e);
return mav;
}
Since i didn't find any solution for this, i wrote some code that manually checks the accept header of the request to determine the format. I then check if the user is logged in and either send the complete stacktrace if he is or a short error message.
I use ResponseEntity to be able to return both JSON or HTML like here.
Code:
#ExceptionHandler(Exception.class)
public ResponseEntity<?> handleExceptions(Exception ex, HttpServletRequest request) throws Exception {
final HttpHeaders headers = new HttpHeaders();
Object answer; // String if HTML, any object if JSON
if(jsonHasPriority(request.getHeader("accept"))) {
logger.info("Returning exception to client as json object");
headers.setContentType(MediaType.APPLICATION_JSON);
answer = errorJson(ex, isUserLoggedIn());
} else {
logger.info("Returning exception to client as html page");
headers.setContentType(MediaType.TEXT_HTML);
answer = errorHtml(ex, isUserLoggedIn());
}
final HttpStatus status = HttpStatus.INTERNAL_SERVER_ERROR;
return new ResponseEntity<>(answer, headers, status);
}
private String errorHtml(Exception e, boolean isUserLoggedIn) {
String error = // html code with exception information here
return error;
}
private Object errorJson(Exception e, boolean isUserLoggedIn) {
// return error wrapper object which will be converted to json
return null;
}
/**
* #param acceptString - HTTP accept header field, format according to HTTP spec:
* "mime1;quality1,mime2;quality2,mime3,mime4,..." (quality is optional)
* #return true only if json is the MIME type with highest quality of all specified MIME types.
*/
private boolean jsonHasPriority(String acceptString) {
if (acceptString != null) {
final String[] mimes = acceptString.split(",");
Arrays.sort(mimes, new MimeQualityComparator());
final String firstMime = mimes[0].split(";")[0];
return firstMime.equals("application/json");
}
return false;
}
private static class MimeQualityComparator implements Comparator<String> {
#Override
public int compare(String mime1, String mime2) {
final double m1Quality = getQualityofMime(mime1);
final double m2Quality = getQualityofMime(mime2);
return Double.compare(m1Quality, m2Quality) * -1;
}
}
/**
* #param mimeAndQuality - "mime;quality" pair from the accept header of a HTTP request,
* according to HTTP spec (missing mimeQuality means quality = 1).
* #return quality of this pair according to HTTP spec.
*/
private static Double getQualityofMime(String mimeAndQuality) {
//split off quality factor
final String[] mime = mimeAndQuality.split(";");
if (mime.length <= 1) {
return 1.0;
} else {
final String quality = mime[1].split("=")[1];
return Double.parseDouble(quality);
}
}
The trick is to have a REST controller with two mappings, one of which specifies "text/html" and returns a valid HTML source. The example below, which was tested in Spring Boot 2.0, assumes the existence of a separate template named "error.html".
#RestController
public class CustomErrorController implements ErrorController {
#Autowired
private ErrorAttributes errorAttributes;
private Map<String,Object> getErrorAttributes( HttpServletRequest request ) {
WebRequest webRequest = new ServletWebRequest(request);
boolean includeStacktrace = false;
return errorAttributes.getErrorAttributes(webRequest,includeStacktrace);
}
#GetMapping(value="/error", produces="text/html")
ModelAndView errorHtml(HttpServletRequest request) {
return new ModelAndView("error.html",getErrorAttributes(request));
}
#GetMapping(value="/error")
Map<String,Object> error(HttpServletRequest request) {
return getErrorAttributes(request);
}
#Override public String getErrorPath() { return "/error"; }
}
References
ModelAndView -- return type for HTML
DefaultErrorAttributes -- data used to render HTML template (and JSON response)
BasicErrorController.java -- Spring Boot source from which this example was derived
The controlleradvice annotation has several properties that can be set, since spring 4. You can define multiple controller advices applying different rules.
One property is "annotations. Probably you can use a specific annotation on the json request mapping or you might find another property more usefull?
Use #ControllerAdvice
Let the exception handler send a DTO containing the field errors.
#ExceptionHandler(MethodArgumentNotValidException.class)
#ResponseStatus(HttpStatus.BAD_REQUEST)
#ResponseBody
public ValidationErrorDTO processValidationError(MethodArgumentNotValidException ex) {
BindingResult result = ex.getBindingResult();
List<FieldError> fieldErrors = result.getFieldErrors();
return processFieldErrors(fieldErrors);
}
This code is of this website:http://www.petrikainulainen.net/programming/spring-framework/spring-from-the-trenches-adding-validation-to-a-rest-api/
Look there for more info.
I am starting to use the new client API library in JAX-RS and really loving it so far. I have found one thing I cannot figure out however. The API I am using has a custom error message format that looks like this for example:
{
"code": 400,
"message": "This is a message which describes why there was a code 400."
}
It returns 400 as the status code but also includes a descriptive error message to tell you what you did wrong.
However the JAX-RS 2.0 client is re-mapping the 400 status into something generic and I lose the good error message. It correctly maps it to a BadRequestException, but with a generic "HTTP 400 Bad Request" message.
javax.ws.rs.BadRequestException: HTTP 400 Bad Request
at org.glassfish.jersey.client.JerseyInvocation.convertToException(JerseyInvocation.java:908)
at org.glassfish.jersey.client.JerseyInvocation.translate(JerseyInvocation.java:770)
at org.glassfish.jersey.client.JerseyInvocation.access$500(JerseyInvocation.java:90)
at org.glassfish.jersey.client.JerseyInvocation$2.call(JerseyInvocation.java:671)
at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
at org.glassfish.jersey.internal.Errors.process(Errors.java:228)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:424)
at org.glassfish.jersey.client.JerseyInvocation.invoke(JerseyInvocation.java:667)
at org.glassfish.jersey.client.JerseyInvocation$Builder.method(JerseyInvocation.java:396)
at org.glassfish.jersey.client.JerseyInvocation$Builder.get(JerseyInvocation.java:296)
Is there some sort of interceptor or custom error handler that can be injected so that I get access to the real error message. I've been looking through documentation but can't see any way of doing it.
I am using Jersey right now, but I tried this using CXF and got the same result. Here is what the code looks like.
Client client = ClientBuilder.newClient().register(JacksonFeature.class).register(GzipInterceptor.class);
WebTarget target = client.target("https://somesite.com").path("/api/test");
Invocation.Builder builder = target.request()
.header("some_header", value)
.accept(MediaType.APPLICATION_JSON_TYPE)
.acceptEncoding("gzip");
MyEntity entity = builder.get(MyEntity.class);
UPDATE:
I implemented the solution listed in the comment below. It is slightly different since the classes have changed a bit in the JAX-RS 2.0 client API. I still think it is wrong that the default behavior is to give a generic error message and discard the real one. I understand why it wouldn't parse my error object, but the un-parsed version should have been returned. I end up having the replicate exception mapping that the library already does.
Thanks for the help.
Here is my filter class:
#Provider
public class ErrorResponseFilter implements ClientResponseFilter {
private static ObjectMapper _MAPPER = new ObjectMapper();
#Override
public void filter(ClientRequestContext requestContext, ClientResponseContext responseContext) throws IOException {
// for non-200 response, deal with the custom error messages
if (responseContext.getStatus() != Response.Status.OK.getStatusCode()) {
if (responseContext.hasEntity()) {
// get the "real" error message
ErrorResponse error = _MAPPER.readValue(responseContext.getEntityStream(), ErrorResponse.class);
String message = error.getMessage();
Response.Status status = Response.Status.fromStatusCode(responseContext.getStatus());
WebApplicationException webAppException;
switch (status) {
case BAD_REQUEST:
webAppException = new BadRequestException(message);
break;
case UNAUTHORIZED:
webAppException = new NotAuthorizedException(message);
break;
case FORBIDDEN:
webAppException = new ForbiddenException(message);
break;
case NOT_FOUND:
webAppException = new NotFoundException(message);
break;
case METHOD_NOT_ALLOWED:
webAppException = new NotAllowedException(message);
break;
case NOT_ACCEPTABLE:
webAppException = new NotAcceptableException(message);
break;
case UNSUPPORTED_MEDIA_TYPE:
webAppException = new NotSupportedException(message);
break;
case INTERNAL_SERVER_ERROR:
webAppException = new InternalServerErrorException(message);
break;
case SERVICE_UNAVAILABLE:
webAppException = new ServiceUnavailableException(message);
break;
default:
webAppException = new WebApplicationException(message);
}
throw webAppException;
}
}
}
}
I believe you want to do something like this:
Response response = builder.get( Response.class );
if ( response.getStatusCode() != Response.Status.OK.getStatusCode() ) {
System.out.println( response.getStatusType() );
return null;
}
return response.readEntity( MyEntity.class );
Another thing you can try (since I don't know where this API puts stuff -- i.e. in the header or entity or what) is:
Response response = builder.get( Response.class );
if ( response.getStatusCode() != Response.Status.OK.getStatusCode() ) {
// if they put the custom error stuff in the entity
System.out.println( response.readEntity( String.class ) );
return null;
}
return response.readEntity( MyEntity.class );
If you would like to generally map REST response codes to Java exception you can add a client filter to do that:
class ClientResponseLoggingFilter implements ClientResponseFilter {
#Override
public void filter(final ClientRequestContext reqCtx,
final ClientResponseContext resCtx) throws IOException {
if ( resCtx.getStatus() == Response.Status.BAD_REQUEST.getStatusCode() ) {
throw new MyClientException( resCtx.getStatusInfo() );
}
...
In the above filter you can create specific exceptions for each code or create one generic exception type that wraps the Response code and entity.
There are other ways to getting a custom error message to the Jersey client besides writing a custom filter. (although the filter is an excellent solution)
1) Pass error message in an HTTP header field.
The detail error message could be in the JSON response and in an additional header field, such as "x-error-message".
The Server adds the HTTP error header.
ResponseBuilder rb = Response.status(respCode.getCode()).entity(resp);
if (!StringUtils.isEmpty(errMsg)){
rb.header("x-error-message", errMsg);
}
return rb.build();
The Client catches the exception, NotFoundException in my case, and reads the response header.
try {
Integer accountId = 2222;
Client client = ClientBuilder.newClient();
WebTarget webTarget = client.target("http://localhost:8080/rest-jersey/rest");
webTarget = webTarget.path("/accounts/"+ accountId);
Invocation.Builder ib = webTarget.request(MediaType.APPLICATION_JSON);
Account resp = ib.get(new GenericType<Account>() {
});
} catch (NotFoundException e) {
String errorMsg = e.getResponse().getHeaderString("x-error-message");
// do whatever ...
return;
}
2) Another solution is to catch the exception and read the response content.
try {
// same as above ...
} catch (NotFoundException e) {
String respString = e.getResponse().readEntity(String.class);
// you can convert to JSON or search for error message in String ...
return;
}
The class WebApplicationException was designed for that but for some reason it ignores and overwrites what you specify as parameter for the message.
For that reason I created my own extension WebAppException that honors the parameters. It is a single class and it doesn't require any response filter or a mapper.
I prefer exceptions than creating a Response as it can be thrown from anywhere while processing.
Simple usage:
throw new WebAppException(Status.BAD_REQUEST, "Field 'name' is missing.");
The class:
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;
import javax.ws.rs.core.Response.Status.Family;
import javax.ws.rs.core.Response.StatusType;
public class WebAppException extends WebApplicationException {
private static final long serialVersionUID = -9079411854450419091L;
public static class MyStatus implements StatusType {
final int statusCode;
final String reasonPhrase;
public MyStatus(int statusCode, String reasonPhrase) {
this.statusCode = statusCode;
this.reasonPhrase = reasonPhrase;
}
#Override
public int getStatusCode() {
return statusCode;
}
#Override
public Family getFamily() {
return Family.familyOf(statusCode);
}
#Override
public String getReasonPhrase() {
return reasonPhrase;
}
}
public WebAppException() {
}
public WebAppException(int status) {
super(status);
}
public WebAppException(Response response) {
super(response);
}
public WebAppException(Status status) {
super(status);
}
public WebAppException(String message, Response response) {
super(message, response);
}
public WebAppException(int status, String message) {
super(message, Response.status(new MyStatus(status, message)). build());
}
public WebAppException(Status status, String message) {
this(status.getStatusCode(), message);
}
public WebAppException(String message) {
this(500, message);
}
}
A much more concise solution for anyone stumbling on this:
Calling .get(Class<T> responseType) or any of the other methods that take the result type as an argument Invocation.Builder will return a value of the desired type instead of a Response. As a side effect, these methods will check if the received status code is in the 2xx range and throw an appropriate WebApplicationException otherwise.
From the documentation:
Throws: WebApplicationException in case the response status code of
the response returned by the server is not successful and the
specified response type is not Response.
This allows to catch the WebApplicationException, retrieve the actual Response, process the contained entity as exception details (ApiExceptionInfo) and throw an appropriate exception (ApiException).
public <Result> Result get(String path, Class<Result> resultType) {
return perform("GET", path, null, resultType);
}
public <Result> Result post(String path, Object content, Class<Result> resultType) {
return perform("POST", path, content, resultType);
}
private <Result> Result perform(String method, String path, Object content, Class<Result> resultType) {
try {
Entity<Object> entity = null == content ? null : Entity.entity(content, MediaType.APPLICATION_JSON);
return client.target(uri).path(path).request(MediaType.APPLICATION_JSON).method(method, entity, resultType);
} catch (WebApplicationException webApplicationException) {
Response response = webApplicationException.getResponse();
if (response.getMediaType().equals(MediaType.APPLICATION_JSON_TYPE)) {
throw new ApiException(response.readEntity(ApiExceptionInfo.class), webApplicationException);
} else {
throw webApplicationException;
}
}
}
ApiExceptionInfo is custom data type in my application:
import lombok.Data;
#Data
public class ApiExceptionInfo {
private int code;
private String message;
}
ApiException is custom exception type in my application:
import lombok.Getter;
public class ApiException extends RuntimeException {
#Getter
private final ApiExceptionInfo info;
public ApiException(ApiExceptionInfo info, Exception cause) {
super(info.toString(), cause);
this.info = info;
}
}
[At least with Resteasy] there is one big disadvantage with the solution offered by #Chuck M and based on ClientResponseFilter.
When you use it based on ClientResponseFilter, your BadRequestException, NotAuthorizedException, ... exceptions are wrapped by javax.ws.rs.ProcessingException.
Clients of your proxy must not be forced to catch this javax.ws.rs.ResponseProcessingException exception.
Without filter, we get an original rest exception. If we catch and handle by default, it does not give us much:
catch (WebApplicationException e) {
//does not return response body:
e.toString();
// returns null:
e.getCause();
}
The problem can be solved on another level, when you extract a description from the error. WebApplicationException exception, which is a parent for all rest exceptions, contains javax.ws.rs.core.Response. Just write a helper method, that in case the exception is of WebApplicationException type, it will also check the response body. Here is a code in Scala, but the idea should be clear. The methord returns a clear description of the rest exception:
private def descriptiveWebException2String(t: WebApplicationException): String = {
if (t.getResponse.hasEntity)
s"${t.toString}. Response: ${t.getResponse.readEntity(classOf[String])}"
else t.toString
}
Now we move a responsibility to show exact error, on the client. Just use a shared exception handler to minimize effort for clients.
The following works for me
Response.status(Response.Status.BAD_REQUEST).entity(e.getMessage()).build();