Volley Server Error with null Network response

Question

Every time I try to use POST method with Volley, I get sever error. I get null value in getCause, and some default value in getNetworkResponse.toString().

If I use GET method, this works fine (I get response from my url).

Can anybody help what can I do?

    Map<String, String> jsonParams = new HashMap<String, String>();
    jsonParams.put("teststr", "abd");

    RequestQueue requestQueue = VolleySingleton.getInstance().getRequestQueue();
    JsonObjectRequest request = new JsonObjectRequest(
            Request.Method.POST,
            url,
            new JSONObject(jsonParams),
            new Response.Listener<JSONObject>() {
                @Override
                public void onResponse(JSONObject response) {

                    try {
                        Toast.makeText(getApplicationContext(), "Success"+response.toString(), Toast.LENGTH_LONG).show();
                    }catch(Exception e){
                        Toast.makeText(getApplicationContext(), "JSON ERROR", Toast.LENGTH_LONG).show();
                    }
                }
            },
            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Log.d("abd", "Error: " + error
                                    + ">>" + error.networkResponse.statusCode
                                    + ">>" + error.networkResponse.data
                                    + ">>" + error.getCause()
                                    + ">>" + error.getMessage());
                }
            }) {

                @Override
                protected Map<String,String> getParams() {
                    HashMap<String, String> params = new HashMap<String, String>();
                    params.put("key", "value");
                    return params;
                }

                @Override
                public Map<String, String> getHeaders() throws AuthFailureError {
                    HashMap<String, String> headers = new HashMap<String, String>();
                    headers.put("Content-Type", "application/json; charset=utf-8");
                    return headers;
                }
    };
    requestQueue.add(request);

Error Log:

Error: Error: com.android.volley.ServerError>>404>>[B@42b1e0d0>>null>>null

UPDATE: networkResponse.statusCode comes as 404, though the url is accessible (and return data if I just use GET method). If I remove header part in POST method, still the same.

the url:

<?php
    $response = array();

    $jsonString = file_get_contents('php://input');
    $jsonObj = json_decode($jsonString, true);

    if(!isset($jsonObj['teststr'])){
        $response["msg"] = "No data.";
    }else{
        $response["msg"] = "Success: ".$jsonObj['teststr'];
    }
    echo json_encode($response);
?>

Answer 1

problem is your Queue. change your volley code to this:

 RequestQueue queue = Volley.newRequestQueue(this);
 String URL = EndPoints.BASE_URL + "/call";
 StringRequest request = new StringRequest(Request.Method.POST, URL,
  new Response.Listener<String>()
  {
    @Override
    public void onResponse(String response) {

      Log.d("onResponse", response);

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

      NetworkResponse response = error.networkResponse;
      String errorMsg = "";
      if(response != null && response.data != null){
        String errorString = new String(response.data);
        Log.i("log error", errorString);
      }
    }
  }
) {
  @Override
  protected Map<String, String> getParams()
  {

    Map<String, String> params = new HashMap<String, String>();
    params.put("key_1","value_1");
    params.put("key_2", "value_2");
    Log.i("sending ", params.toString());

    return params;
  }

};


 // Add the realibility on the connection.
 request.setRetryPolicy(new DefaultRetryPolicy(10000, 1, 1.0f));

  // Start the request immediately
    queue.add(request);  

and your php (laravel) code to this:

    $response['success'] = true;
    $response['user']['tell'] = $user->tell;
    $response['user']['code'] = $user->code;
    $response['user']['time'] = $time;
    $response['user']['register_state'] = '1'
    return response()->json($response, 200);

Answer 2

First, try to make sure your server works well. You can use Postman(chrome plug-in) or any other way to send a post request to the url and see what it responses.

After make sure there's no problem with your server, let us solve the problem with volley.

There's some problem with JsonObjectRequest when you use POST method. like this Volley JsonObjectRequest Post request not working.

I suggest you use StringRequest first and overwrite the getParams method like you did before. After you survive this task, you can try to write your own request, not very difficult but very useful.

I also suggest add request.setShouldCache(false) before requestQueue.add(request);. By default, volley saves the response in its cache and this behavior may cause some strange problem.