POST request with Retrofit giving 500

Question

I have the following Body sent via postman return just fine (as raw JSON)

{"payload":{"email":"","username":"","password":""}}

However when i try to send it via Retrofit as follows, it doesn't work (gives 500):

public Observable<JsonObject> signup(String email, String userName, String password) {
    JsonObject data = new JsonObject();
    JsonObject payload = new JsonObject();

    data.addProperty("email", email);
    data.addProperty("username", userName);
    data.addProperty("password", password);
    payload.add("payload", data);

    return mShoutApiService.signup(payload);
}

Service call and adapter are as follows

service:

@POST("/signup")
Observable<JsonObject> signup(@Body JsonObject payload);

adapter:

private RestAdapter createRestAdapter(String hostUrl, GsonConverter gsonConverter, OkClient okClient) {
    return new RestAdapter.Builder()
            .setClient(okClient)
            .setConverter(gsonConverter)
            .setEndpoint(hostUrl)
            .setLogLevel(LogLevel.FULL)
            .setLog(new AndroidLog("SHOUT_LOG"))
            .build();
}

private GsonConverter getGsonConverter(Gson gson) {
    return new GsonConverter(gson);
}

private OkClient getOkClient() {
    OkHttpClient okHttpClient = new OkHttpClient();
    okHttpClient.setReadTimeout(READ_TIMEOUT, TimeUnit.SECONDS);
    okHttpClient.setConnectTimeout(CONNECT_TIMEOUT, TimeUnit.SECONDS);

    return new OkClient(okHttpClient);
}

Logs show as follows

03-23 05:04:00.380 2442-3468/shout.surge.com.shout D/SHOUT_LOG: --->       HTTP POST http://shout-api.herokuapp.com/signup
03-23 05:04:00.380 2442-3468/shout.surge.com.shout D/SHOUT_LOG: Content-Type: application/json; charset=UTF-8
03-23 05:04:00.380 2442-3468/shout.surge.com.shout D/SHOUT_LOG: Content-Length: 52
03-23 05:04:00.384 2442-3468/shout.surge.com.shout D/SHOUT_LOG: {"payload":{"email":"","username":"","password":""}}
03-23 05:04:00.384 2442-3468/shout.surge.com.shout D/SHOUT_LOG: ---> END HTTP (52-byte body)
03-23 05:04:09.180 2442-3468/shout.surge.com.shout D/SHOUT_LOG: <--- HTTP  500 http://shout-api.herokuapp.com/signup (8796ms)

It appears they are the exact same call but for some reason it fails in my mobile app. any insight as to what I'm missing would be great!

Answer 1

I took a look at your issue and as I suspected it's indeed related with a small difference in the calls made in the app with the calls made from postman. Unfortunately I cannot explain to you why this happens because being a 500 it's most likely a faulty implementation on the server side.

The issue got solved for me when I added the header Accept: application/json like so:

@Headers("Accept: application/json")
@POST("/signup")
Observable<JsonObject> signup(@Body JsonObject payload);

I've noticed that the tool I'm using (Advanced REST Client for chrome) was adding said header to every call.

When I remove this header I get the 500 you were experiencing. You can also use Accept: */*, but I'm not sure this is a good practise.

I'm sorry I don't have enough to tell you why this happens, but it fixed the issue for me. I did try it in an android app.