Retrofit 2.0 how to get deserialised error response.body

I'm using Retrofit 2.0.0-beta1.

In tests i have an alternate scenario and expect error HTTP 400

I would like to have retrofit.Response<MyError> response but response.body() == null

MyError is not deserialised - i see it only here

response.errorBody().string()

but it doesn't give me MyError as object

Solution 1:

I currently use a very easy implementation, which does not require to use converters or special classes. The code I use is the following:

public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
    DialogHelper.dismiss();

    if (response.isSuccessful()) {
        // Do your success stuff...
    } else {
        try {
            JSONObject jObjError = new JSONObject(response.errorBody().string());
            Toast.makeText(getContext(), jObjError.getJSONObject("error").getString("message"), Toast.LENGTH_LONG).show();
        } catch (Exception e) {
            Toast.makeText(getContext(), e.getMessage(), Toast.LENGTH_LONG).show();
        }
    }
}

A point to note here is that response.errorBody().string() will return the correct value only once. If you call it again, it will return an empty string. So in case you want to reuse it, store the value in a variable with the first call.

Solution 2:

ErrorResponse is your custom response object

Kotlin

val gson = Gson()
val type = object : TypeToken<ErrorResponse>() {}.type
var errorResponse: ErrorResponse? = gson.fromJson(response.errorBody()!!.charStream(), type)

Java

Gson gson = new Gson();
Type type = new TypeToken<ErrorResponse>() {}.getType();
ErrorResponse errorResponse = gson.fromJson(response.errorBody.charStream(),type);

Solution 3:

I solved it by:

 if(!response.isSuccessful()){
       Gson gson = new Gson();
       MyErrorMessage message=gson.fromJson(response.errorBody().charStream(),MyErrorMessage.class);
       if(message.getCode()==ErrorCode.DUPLICATE_EMAIL_ID_CODE){
                  //DO Error Code specific handling                        
        }else{
                 //DO GENERAL Error Code Specific handling                               
        }
    }

MyErrorMessage Class:

  public class MyErrorMessage {
     private int code;
     private String message;

     public int getCode() {
        return code;
     }

     public void setCode(int code) {
        this.code = code;
     }

     public String getMessage() {
         return message;
     }

     public void setMessage(String message) {
        this.message = message;
     }
   }

Solution 4:

In Retrofit 2.0 beta2 this is the way that I'm getting error responses:

1. Synchronous

   try {
      Call<RegistrationResponse> call = backendServiceApi.register(data.in.account, data.in.password,
              data.in.email);
      Response<RegistrationResponse> response = call.execute();
      if (response != null && !response.isSuccess() && response.errorBody() != null) {
          Converter<ResponseBody, BasicResponse> errorConverter =
                  MyApplication.getRestClient().getRetrofitInstance().responseConverter(BasicResponse.class, new Annotation[0]);
          BasicResponse error = errorConverter.convert(response.errorBody());
          //DO ERROR HANDLING HERE
          return;
      }
      RegistrationResponse registrationResponse = response.body();
      //DO SUCCESS HANDLING HERE
   } catch (IOException e) {
      //DO NETWORK ERROR HANDLING HERE
   }
   

2. Asynchronous

   Call<BasicResponse> call = service.loadRepo();
   call.enqueue(new Callback<BasicResponse>() {
       @Override
       public void onResponse(Response<BasicResponse> response, Retrofit retrofit) {
           if (response != null && !response.isSuccess() && response.errorBody() != null) {
               Converter<ResponseBody, BasicResponse> errorConverter =
                   retrofit.responseConverter(BasicResponse.class, new Annotation[0]);
               BasicResponse error = errorConverter.convert(response.errorBody());
               //DO ERROR HANDLING HERE
               return;
           }
           RegistrationResponse registrationResponse = response.body();
           //DO SUCCESS HANDLING HERE
       }
   
       @Override
       public void onFailure(Throwable t) {
           //DO NETWORK ERROR HANDLING HERE
       }
   });
   

Update for Retrofit 2 beta3:

1. Synchronous - not changed

2. Asynchronous - Retrofit parameter was removed from onResponse

   Call<BasicResponse> call = service.loadRepo();
   call.enqueue(new Callback<BasicResponse>() {
       @Override
       public void onResponse(Response<BasicResponse> response) {
           if (response != null && !response.isSuccess() && response.errorBody() != null) {
               Converter<ResponseBody, BasicResponse> errorConverter =
                   MyApplication.getRestClient().getRetrofitInstance().responseConverter(BasicResponse.class, new Annotation[0]);
               BasicResponse error = errorConverter.convert(response.errorBody());
               //DO ERROR HANDLING HERE
               return;
           }
           RegistrationResponse registrationResponse = response.body();
           //DO SUCCESS HANDLING HERE
       }
   
       @Override
       public void onFailure(Throwable t) {
           //DO NETWORK ERROR HANDLING HERE
       }
   });