Retrofit 2.0 - How to get response body for 400 Bad Request error?

Question

So when I make a POST API call to my server, I get a 400 Bad Request error with JSON response.

{     "userMessage": "Blah",     "internalMessage": "Bad Request blah blah",     "errorCode": 1 } 

I call it by

Call.enqueue(new Callback<ResponseBody>() {     @Override     public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {         //AA     }      @Override     public void onFailure(Call<ResponseBody> call, Throwable t) {         //BB     } } 

However the problem is that once I get the response, onFailure() is invoke so that //BB is called. Here, I have no way to access the JSON response. When I log the api request and response, it doesn't show JSON response at all. And Throwable t is IOException. However, strangely, when I make the same call on Postman, it does return the expected JSON response with 400 error code.

So my question is how can I get the json response when I get 400 Bad Request error? Should I add something to okhttpclient?

Thanks

Answer 1

You can do it in your onResponse method, remember 400 is a response status not an error:

if (response.code() == 400) {                   Log.v("Error code 400",response.errorBody().string()); } 

And you can handle any response code except 200-300 with Gson like that:

if (response.code() == 400) {    Gson gson = new GsonBuilder().create();    ErrorPojoClass mError=new ErrorPojoClass();    try {        mError= gson.fromJson(response.errorBody().string(),ErrorPojoClass.class);        Toast.makeText(context, mError.getDescription(), Toast.LENGTH_LONG).show();    } catch (IOException e) {        // handle failure to read error    }         } 

Add this to your build.gradle : compile 'com.google.code.gson:gson:2.7'

If you want create Pojo class go to Json Schema 2 Pojo and paste your example Json response. Select source type Json and annotation Gson .

Answer 2

You can try the below code to get 400 response. You can get error response from errorBody() method.

Call.enqueue(new Callback<ResponseBody>() {     @Override     public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {         //get success and error response here  if (response.code() == 400) {                 if(!response.isSuccessful()) {                     JSONObject jsonObject = null;                     try {                         jsonObject = new JSONObject(response.errorBody().string());                         String userMessage = jsonObject.getString("userMessage");                         String internalMessage = jsonObject.getString("internalMessage");                         String errorCode = jsonObject.getString("errorCode");                     } catch (JSONException e) {                         e.printStackTrace();                     }                 }             }      @Override     public void onFailure(Call<ResponseBody> call, Throwable t) {         //get failure response here     } } } 

EDIT: Fixed method name from toString to string