errorBody with retrofit2 and kotlin - kotlin

I am trying to get the error returned by a service (when starting with invalid credentials) rest api but for some reason errorBody does not catch it from my answer.
The correct answer I receive without problems but when I get an error I can't solve what the server sends me.
Sorry for my English, I had to use the translator
This is the part where I should get the error
override fun postLogin(callback: OperationCallBack<ResponseToken>, user: Login) {
call = Api.build()?.login(user)
call?.enqueue(object :Callback<ResponseToken>{
override fun onFailure(call: Call<ResponseToken>, t: Throwable) {
callback.onError(t.message)
}
override fun onResponse(call: Call<ResponseToken>, response: Response<ResponseToken>) {
Log.v(TAG, "ErrorMensaje: ${response.message()}")
Log.v(TAG, "ErrorBodyToString: ${response.errorBody().toString()}")
response.body()?.let {
if(response.isSuccessful && (it.isSuccess())){
Log.v(TAG, "token ${it.token}")
callback.onSuccess(it)
}else{
Log.v(TAG, "token ${it.token}")
callback.onError("Error ocurrido")
}
}
}
})
}
errorBody shows me only with toString otherwise it returns null. With toString this is what I get
2020-06-10 19:26:05.095 26590-26590/com.umbani.umbani V/CONSOLE: ErrorMensaje:
2020-06-10 19:26:05.095 26590-26590/com.umbani.umbani V/CONSOLE: ErrorBodyToString: okhttp3.ResponseBody$Companion$asResponseBody$1#fcb3843
The okHttp console shows the error as it comes from the server, which I cannot catch
D/OkHttp: {"success":true,"error":{"message":"Invalid credentials"}}
It is not a problem to convert with Gson or another converter. I can do that. I have done so with the positive response.
I have seen many answers on StackOverFlow and none has helped me.
Thank you
UPDATE:
I found the solution in this answer:
https://stackoverflow.com/a/55835083/10372439
SOLUTION:
Replace toString () to string ()
response.errorBody()!!.string()

Try overriding the onFailure block, then cast it with the right object
override fun onFailure(call: Call< ResponseToken >, t: Throwable) {
if (t is HttpException) {
try {
val errorStringRaw: String? = t.response()?.errorBody()?.string()
//Parse error message; format is api specific; we can't make a generic approach for this as of the moment
val type = object : TypeToken<ResponseBody?>() {}.type
val response: ResponseBody = Gson().fromJson(errorStringRaw, type)
} catch (e: Exception) {
}
}
}

Related

How to convert kotlin Result type from List<Result<T>> to Result<List<T>>

I have List<Result<String>> and I would like to convert it to Result<List<String>>. I understand that List<Result<String>> could have both failure and successful results but I would like to terminate in the first failure.
If you want to have a failure as soon there is one Result that is a failure you can do this :
fun <T> List<Result<T>>.toResult() = if (any { it.isFailure }) {
Result.failure<List<Result<Any>>>(Throwable("A result has errors"))
} else {
Result.success(map { it.getOrNull() })
}
With this code, you get a failure as soon as there is one value has a failure.
Or if you don't care handling the error yourself :
fun <T> List<Result<T>>.toResult() = runCatching {
Result.success(map { it.getOrThrow() })
}
In most libraries this function is known as sequence.
Kotlin's Arrow library implements it for its implementation of the type Either, which is a generalization of Result: https://arrow-kt.io/docs/apidocs/arrow-core/arrow.core/sequence.html
With Arrow's Either you would write:
val xs: List<Result<String>> = ...
val ys: Result<List<String>> = xs.sequence()
The Kotlin stdlib does not seem to have it. You could define it as an extension method using getOrThrow, catching any thrown Throwable and wrapping in a Resultagain:
fun <T> List<Result<T>>.sequence(): Result<List<T>> = try {
Result.success(this.map { it.getOrThrow() })
}
catch (e:Throwable) { Result.failure(e) }

Crash in coroutine

My function is quite straightforward,
Main Thread: Initializes a variable ->
Background Thread: Fire network request, assign the result back to the previous variable ->
Main Thread: Display that variable
Code below:
suspend fun createCity(context: Context, newCity: MutableLiveData<NewIdea>, mapBody: Map<String, String>, token: String) {
lateinit var response: NewIdea
try {
withContext(Dispatchers.IO) {
val map = generateRequestBody(mapBody)
response = webservice.createIdea(tripId, map, "Bearer $token")
getTrip(context, token)
}
} catch (e: Exception) {
Log.e(TAG, e.message)
}
newCity.value = response
}
But sometimes (it only happened 2 times actually) crashlytics reports crash for this line newCity.value = response
Fatal Exception: kotlin.UninitializedPropertyAccessException: lateinit property response has not been initialized
I don't really understand how that can happen.
Is this the correct way to return value from coroutine function?
thanks
Well if try block fails, it might happen that the lateinit variable isn't set at all. You should put the ui update code inside the try block as well, and handle the Exception separately:
Sidenote: withContext is well-optimized to return values, so you can make use of it.
suspend fun createCity(context: Context, newCity: MutableLiveData<NewIdea>, mapBody: Map<String, String>, token: String) {
try {
val response: NewIdea = withContext(Dispatchers.IO) {
val map = generateRequestBody(mapBody)
// does createIdea() first store it in var, then does getTrip(), then returns the result of createIdea() stored previously
webservice.createIdea(tripId, map, "Bearer $token").also { getTrip(context, token) } // ^withContext
}
newCity.value = response
} catch (e: Exception) {
Log.e(TAG, e.message)
}
}
A quick tip (optional): You can wrap the UI updating code with a withContext that dispatches the work to Dispatchers.Main when not running in main thread, while if running in main do nothing:
withContext(Dispatchers.Main.immediate) {
val response: NewIdea = withContext(Dispatchers.IO) {
val map = generateRequestBody(mapBody)
// does createIdea() first store it in var, then does getTrip(), then returns the result of createIdea() stored previously
webservice.createIdea(tripId, map, "Bearer $token").also { getTrip(context, token) } // ^withContext
}
newCity.value = response
}

How to override in Kotiln Volley JsonObjectRequest class?

I'm writing a Kotlin app that has a class. I need that class to extend JsonObjectRequest, since I need to override the function
override fun parseNetworkResponse(response: NetworkResponse?): Response<T>
That's because I need to interpret in Kotlin the HTTP response code the server is sending.
However, I admit to being new to Kotlin and haven't managed to figure out how to extend the JsonObjectRequest class. I keep running into silly compiler issues.
Can someone provide a quick example of that?
After a bit of iteration, i managed to finally figure it out. Posting it here since it may be useful to others -
class DataRequest(
method: Int,
uri: String,
jsonObject: JSONObject,
listener: Response.Listener<JSONObject>,
errorListener: Response.ErrorListener
) :
JsonObjectRequest(method, uri, jsonObject, listener, errorListener)
{
override fun parseNetworkResponse(response: NetworkResponse): Response<JSONObject>
{
try
{
val jsonString = String(
response.data,
Charset.forName(HttpHeaderParser.parseCharset(response.headers))
)
return Response.success(
JSONObject(jsonString), HttpHeaderParser.parseCacheHeaders(response)
)
} catch (e: UnsupportedEncodingException)
{
return Response.error(ParseError(e))
} catch (je: JSONException)
{
return Response.error(ParseError(je))
}
}
}

Retrofit's `enqueue()` doesn't re-assign value of object in time for the return statement?

I'm making a call to the API and the response body is assigned to an object inside Retrofit's enqueue(), the problem is that enqueue finishes too quickly for the value to be assigned before the return statement of the function body is called.
Previously, I was using MutableLiveData before and it took care of that because it's always observing the data and when it changes it assigns it with no problem but now I don't want to use any MutableLiveData or Observables because I'm trying to prepare the data before any UI is actually drawn on the screen.
fun getResponse(
weatherLocationCoordinates: WeatherLocation
): RequestResponse {
weatherApiService.getCurrentWeather(
weatherLocationCoordinates.latitude,
weatherLocationCoordinates.longitude
).enqueue(object : Callback<WeatherResponse> {
override fun onResponse(
call: Call<WeatherResponse>,
response: Response<WeatherResponse>
) {
if (response.isSuccessful) {
// This where I do the assigning
requestResponse = RequestResponse(response.body(), true)
}
}
override fun onFailure(call: Call<WeatherResponse>, t: Throwable) {
requestResponse = RequestResponse(null, false)
}
})
// When this is called, enqueue is still not finished
// therefore I get the wrong value, I get the previously set initialization value of the obj.
return requestResponse
}
Should I be using Callbacks or something else? I'm not sure on how to implement the callback.
Following up on the comments here's an approach with callbacks:
Let's suppose we change the method signature to:
fun getResponse(
weatherLocationCoordinates: WeatherLocation,
onSuccess: (WeatherResponse) -> Unit = {},
onError: (Throwable) -> Unit = {}
) {
weatherApiService.getCurrentWeather(
weatherLocationCoordinates.latitude,
weatherLocationCoordinates.longitude
).enqueue(object : Callback<WeatherResponse> {
override fun onResponse(
call: Call<WeatherResponse>,
response: Response<WeatherResponse>
) {
if (response.isSuccessful) {
onSuccess(response.body())
} else {
onError(CustomHttpExceptionWithErrorDescription(response))
}
}
override fun onFailure(call: Call<WeatherResponse>, t: Throwable) {
onError(t)
}
})
}
CustomHttpExceptionWithErrorDescription will have to be something you code that can simply parse the error gotten from the server. Anything that is not 2XX status code
This method accepts 2 extra parameters - one gets called upon success the other on error. The idea is to call it like:
getResponse(
weatherLocationCoordinates,
onSuccess = {
// do something with response
},
onError = {
// do something with the error
}
)
Because they have default parameters you actually don't need to specify both callbacks. Just the one you are interested in. Examples:
// react only to successes
getResponse(
weatherLocationCoordinates,
onSuccess = {
// do something with response
}
)
// react only to errors
getResponse(weatherLocationCoordinates) {
// do something with the error
}
// just call the network calls and don't care about success or error
getResponse(weatherLocationCoordinates)

kotlin: retrofit2 getting 404 url not found error

Getting Response{protocol=http/1.1, code=404, message=Not Found, url=https://test.test.com/service/one}
The url is correct as postman works fine.
I have tried looking into this error but most things come back with URL was in correct. and the error itself is vague.
code that starts it. the builder is a json string that is valid. I have tested it in postman.
CoroutineScope(Dispatchers.Default).launch {
val call = submitService.submitCarton(builder.toString())
Log.d("submit", "begining")
withContext(Dispatchers.Main) {
if (call.isSuccessful) {
Log.d("submit",call.body() as String)
} else {
Log.d("submit", "else....")
}
}
}
service factory:
fun makeSubmitService() : SubmitService{
val url = "https://test.test.com/service/"
return Retrofit.Builder().baseUrl(url)
.client(okHttpClient).addConverterFactory(GsonConverterFactory.create())
.build().create(SubmitService::class.java)
}
interface:
interface SubmitService {
#POST("one")
suspend fun submitCarton(#Body json: String): Response<myModel>
}
Expected results are a json response however I am not getting that far.
edit: I created a okhttpclient and did a request manual and I get a message 200 ok.
code for my test
val JSON = MediaType.parse("application/json; charset=utf-8")
val client = OkHttpClient()
val body = "some json"
val requestBody = RequestBody.create(JSON, body)
val request = Request.Builder()
.url("https://test.test.com/service/one")
.post(requestBody)
.build()
client.newCall(request).enqueue(object : Callback {
override fun onFailure(request: Request, e: IOException) {
Log.e("test", e.toString())
}
#Throws(IOException::class)
override fun onResponse(response: Response) {
Log.d("test", response.toString())
}
})
Solved it myself.
Issue was dumb, retrofit2 was giving 404 even though the web service was returning a error message.
added
implementation 'com.squareup.okhttp3:logging-interceptor:3.12.1'
private val interceptor = HttpLoggingInterceptor().setLevel(HttpLoggingInterceptor.Level.BODY)
private val okHttpClient = OkHttpClient().newBuilder()
.connectTimeout(1, TimeUnit.MINUTES)
.readTimeout(30, TimeUnit.SECONDS)
.writeTimeout(20, TimeUnit.SECONDS)
.addInterceptor(interceptor)
.build()
found out retrofit was sending a very unformatted string
"{ \"all my json filled with \" }"
instead of
{ json }
fixed it by adding
.addConverterFactory(ScalarsConverterFactory.create())
to my service factory
for anyone wondering why I am basically creating the json as a string instead of using a JSON object is because the service I talk to really really wants it to be in a very specific order which JSON just don't care about it however it wants it to look like JSON as well...