How to get error message description using Volley

Question

I'm sending an http request from Android Java using the Volley library to a c# backend. The backend application responds with a error code and description as intended, as well as a StatusDescription. I can see the response status description through wireshark but do not know how to get the description string on the android side.

    final JsonObjectRequest request = new JsonObjectRequest(JsonObjectRequest.Method.POST,
                                url,json,
                            new Response.Listener<JSONObject>() {

                                @Override
                                public void onResponse(JSONObject response) {
                                    TextView mTextView = (TextView) findViewById(R.id.output);
                                    print("Success");
                                }
                            }, new Response.ErrorListener() {

                                @Override
                                public void onErrorResponse(VolleyError error) {
                                    TextView mTextView = (TextView) findViewById(R.id.output);
                                    print("Failure (" + error.networkResponse.statusCode + ")");
//Trying to get the error description/response phrase here
                            }
                        }
                    );

This is the C# code processing the request:

[WebInvoke(Method = "POST", UriTemplate = "users", BodyStyle = WebMessageBodyStyle.Wrapped, RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)] [OperationContract] void addUser(String username, String firstname, String lastname, String email, String hash) { Console.WriteLine(DateTime.Now + " Packet receieved");

        //Stores the response object that will be sent back to the android client
        OutgoingWebResponseContext response = WebOperationContext.Current.OutgoingResponse;
        String description = "User added";
        response.StatusCode = System.Net.HttpStatusCode.OK;

        //Tries to add the new user
        try
        {
            userTable.Insert(username,firstname,lastname,email,hash);
        }
        catch (SqlException e)
        {
            //Default response is a conflict
            response.StatusCode = System.Net.HttpStatusCode.Conflict;

            description = "Bad Request (" + e.Message + ")";

            //Check what the conflict is
            if (userTable.GetData().AsEnumerable().Any(row => username == row.Field<String>("username")))
            {
                description = "Username in use";
            }
            else if (userTable.GetData().AsEnumerable().Any(row => email == row.Field<String>("email")))
            {
                description = "Email address in use";
            }
            else
            {
                response.StatusCode = System.Net.HttpStatusCode.BadRequest;
            }
        }

        //display and respond with the description
        Console.WriteLine(description);
        response.StatusDescription = description;
    }

I've looked through other peoples questions but can't seem to find the answer I'm looking for. Anyone know how to do this? Many methods I have tried resulted in empty curly braces, indicating JSON with an empty body. I am trying specifically to get the status description.

Lippi

Answer 1

Try with this custom method:

public void parseVolleyError(VolleyError error) {
        try {
            String responseBody = new String(error.networkResponse.data, "utf-8");
            JSONObject data = new JSONObject(responseBody);
            JSONArray errors = data.getJSONArray("errors");
            JSONObject jsonMessage = errors.getJSONObject(0);
            String message = jsonMessage.getString("message");
            Toast.makeText(getApplicationContext(), message, Toast.LENGTH_LONG).show();
        } catch (JSONException e) {
        } catch (UnsupportedEncodingException errorr) {
        }
    }

It will show toast with error message from the request. Call this in onErrorResponse method in your volley request:

new Response.ErrorListener() {
                        @Override
                        public void onErrorResponse(VolleyError error) {
                           parseVolleyError(error);
                        }
                    }

Planer

for "utf-8", use StandardCharsets.UTF_8, this is to avoid using UnsupportedEncodingException catch block. – Comb

Answer 2

The data field of networkResponse is a JSON string of the form:

{"response":false,"msg":"Old Password is not correct."}

So you need to get the value corresponding to "msg" field, like this (ofcourse with all exception catching):

String responseBody = new String(error.networkResponse.data, "utf-8");
JSONObject data = new JSONObject(responseBody);
String message = data.optString("msg");

Tested with Volley 1.1.1

Prognosticate

Answer 3

IMO, you should override parseNetworkError as below:

@Override
protected VolleyError parseNetworkError(VolleyError volleyError) {
    String json;
    if (volleyError.networkResponse != null && volleyError.networkResponse.data != null) {
        try {
            json = new String(volleyError.networkResponse.data,
                    HttpHeaderParser.parseCharset(volleyError.networkResponse.headers));
        } catch (UnsupportedEncodingException e) {
            return new VolleyError(e.getMessage());
        }
        return new VolleyError(json);
    }
    return volleyError;
}

Then, inside onErrorResponse(VolleyError error), you can use Log.e(LOG_TAG, error.toString()); for example. Hope it helps!

Cutright

Thanks for your response, it helped! – Lippi

Answer 4

you have to override parseNetworkError and deliverError methods and you can get errormessage from them.

Shopper

Could you provide some code as an example? Not too sure how to do it. – Lippi

Answer 5

Example to override methods :

final JsonObjectRequest request = new JsonObjectRequest(JsonObjectRequest.Method.POST,
            url, json,
            new Response.Listener<JSONObject>() {

                @Override
                public void onResponse(JSONObject response) {
                    TextView mTextView = (TextView) findViewById(R.id.output);
                    print("Success");
                }
            }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            TextView mTextView = (TextView) findViewById(R.id.output);
            print("Failure (" + error.networkResponse.statusCode + ")");
        }
    }){
        @Override
        protected VolleyError parseNetworkError(VolleyError volleyError) {
            return super.parseNetworkError(volleyError);
        }

        @Override
        public void deliverError(VolleyError error) {
            super.deliverError(error);
        }
    };

Shopper

Thanks for this, it helped :) – Lippi

Answer 6

for get type error you can use this code

JsonArrayRequest request=new JsonArrayRequest(Request.Method.POST,Url,input,response ->{}  ,error -> {

 if (error instanceof TimeoutError) {
      //For example your timeout is 3 seconds but the operation takes longer
 }

 else if (error instanceof ServerError) {
        //error in server
 }

 else if (error instanceof NetworkError) {
        //network is disconnect
 }

 else if (error instanceof ParseError) {
        //for cant convert data
 }

 else {
        //other error
 }
 });

for get error message you can use this code

String Message=error.toString();

Protean

Answer 7

For Kotlin, you can use this in your request class or singleton

 override fun parseNetworkError(volleyError: VolleyError): VolleyError {
            val json: String
            if (volleyError.networkResponse != null && volleyError.networkResponse.data != null) {
                    json = try {
                            String(volleyError.networkResponse.data,
                                    Charset.forName(HttpHeaderParser.parseCharset(volleyError.networkResponse.headers)))
                    } catch (e: UnsupportedEncodingException) {
                            return VolleyError(e.message)
                    }
                    return VolleyError(json)
            }
            return volleyError
    }

Mcgray

Answer 8

Use this way

  Response.ErrorListener {

            var errorMsg =it.message

        }

Mcphail