Retrofit 2.0 how to get deserialised error response.body

Question

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.Respons

Answer 1

val error = JSONObject(callApi.errorBody()?.string() as String)
            CustomResult.OnError(CustomNotFoundError(userMessage = error["userMessage"] as String))

open class CustomError (
    val traceId: String? = null,
    val errorCode: String? = null,
    val systemMessage: String? = null,
    val userMessage: String? = null,
    val cause: Throwable? = null
)

open class ErrorThrowable(
    private val traceId: String? = null,
    private val errorCode: String? = null,
    private val systemMessage: String? = null,
    private val userMessage: String? = null,
    override val cause: Throwable? = null
) : Throwable(userMessage, cause) {
    fun toError(): CustomError = CustomError(traceId, errorCode, systemMessage, userMessage, cause)
}


class NetworkError(traceId: String? = null, errorCode: String? = null, systemMessage: String? = null, userMessage: String? = null, cause: Throwable? = null):
    CustomError(traceId, errorCode, systemMessage, userMessage?: "Usted no tiene conexión a internet, active los datos", cause)

class HttpError(traceId: String? = null, errorCode: String? = null, systemMessage: String? = null, userMessage: String? = null, cause: Throwable? = null):
    CustomError(traceId, errorCode, systemMessage, userMessage, cause)

class UnknownError(traceId: String? = null, errorCode: String? = null, systemMessage: String? = null, userMessage: String? = null, cause: Throwable? = null):
    CustomError(traceId, errorCode, systemMessage, userMessage?: "Unknown error", cause)

class CustomNotFoundError(traceId: String? = null, errorCode: String? = null, systemMessage: String? = null, userMessage: String? = null, cause: Throwable? = null):
    CustomError(traceId, errorCode, systemMessage, userMessage?: "Data not found", cause)`

Answer 2

In Kotlin:

val call = APIClient.getInstance().signIn(AuthRequestWrapper(AuthRequest("1234567890z", "12341234", "nonce")))
call.enqueue(object : Callback<AuthResponse> {
    override fun onResponse(call: Call<AuthResponse>, response: Response<AuthResponse>) {
        if (response.isSuccessful) {

        } else {
            val a = object : Annotation{}
            val errorConverter = RentalGeekClient.getRetrofitInstance().responseBodyConverter<AuthFailureResponse>(AuthFailureResponse::class.java, arrayOf(a))
            val authFailureResponse = errorConverter.convert(response.errorBody())
        }
    }

    override fun onFailure(call: Call<AuthResponse>, t: Throwable) {
    }
})

Answer 3

solved it by:

Converter<MyError> converter = 
    (Converter<MyError>)JacksonConverterFactory.create().get(MyError.class);
MyError myError =  converter.fromBody(response.errorBody());

Answer 4

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);

Answer 5

It's actually very straight forward.

Kotlin:

val jsonObj = JSONObject(response.errorBody()!!.charStream().readText())
responseInterface.onFailure(jsonObj.getString("msg"))

Java:

    if(response.errorBody()!=null){
    JSONObject jsonObj = new JSONObject(TextStreamsKt.readText(response.errorBody().charStream()));
        responseInterface.onFailure(jsonObj.getString("msg"));
    }else{
        responseInterface.onFailure("you might want to return a generic error message.");
    }

Tested on retrofit:2.5.0. Read the text from the charStream which will give you a String, then parse to JSONObject.

Adios.

Answer 6

Here is elegant solution using Kotlin extensions:

data class ApiError(val code: Int, val message: String?) {
    companion object {
        val EMPTY_API_ERROR = ApiError(-1, null)
    }
}

fun Throwable.getApiError(): ApiError? {
    if (this is HttpException) {
        try {
            val errorJsonString = this.response()?.errorBody()?.string()
            return Gson().fromJson(errorJsonString, ApiError::class.java)
        } catch (exception: Exception) {
            // Ignore
        }
    }
    return EMPTY_API_ERROR
}

and usage:

showError(retrofitThrowable.getApiError()?.message)