Volley deliverResponse not being called

Question

I am using Volley and I see the parseNetworkResponse being called and all ok. The parsing is fine I can see in the logs and I don’t return null. But for some reason the deliverResponse is not being called? How could reason why this can happen or how I could debug this?

Even this:

@Override
        protected Response<Object> parseNetworkResponse(NetworkResponse response) {
            Log.i(“TEST”, "Returning nothing from dummy parseNetworkResponse....");
            Response<Object> jsonResponse = Response.success(new Object(), HttpHeaderParser.parseCacheHeaders(response));
            Log.i("TEST", "Returning nothing....");
            return jsonResponse;
        } 

does not end up in calling the deliverResponse although I can see the logs in the LOGCAT

UPDATE:
I went through the debugger and I end up in the code in NetworkDispatcher (after network-parse-complete and post-response) request.markDelivered(); mDelivery.postResponse(request, response); Then the code in ExecutorDelivery.postResponse is executed:

mResponsePoster.execute(new ResponseDeliveryRunnable(request, response, runnable));

That would eventually call the mRequest.deliverResponse(mResponse.result); but when I add a breakpoint in ResponseDeliveryRunnable.run the code does not break and so I assume that the runnable that would call the deliverResponse is not being run.
Any idea why this could happen?

Answer 1

Check your volley logs for clues, as some of the above answerers mentioned. I use an alias to filter volley logs like so:

alias vlog='adb shell setprop log.tag.Volley VERBOSE && adb logcat -Cv threadtime | grep -Ii '\''volley'\'''

When I hit this exact issue, I noticed that the specific requests in question would show the following in the logs:

04-02 17:22:41.309 21639 21639 D Volley  : [1] MarkerLog.finish: (+0   ) [ 1] add-to-queue
04-02 17:22:41.309 21639 21639 D Volley  : [1] MarkerLog.finish: (+10  ) [233] cache-queue-take
04-02 17:22:41.310 21639 21639 D Volley  : [1] MarkerLog.finish: (+0   ) [233] cache-miss
04-02 17:22:41.313 21639 21639 D Volley  : [1] MarkerLog.finish: (+1   ) [234] network-queue-take
04-02 17:22:41.314 21639 21639 D Volley  : [1] MarkerLog.finish: (+227 ) [234] network-http-complete
04-02 17:22:41.314 21639 21639 D Volley  : [1] MarkerLog.finish: (+3   ) [234] network-parse-complete
04-02 17:22:41.315 21639 21639 D Volley  : [1] MarkerLog.finish: (+0   ) [234] post-response
04-02 17:22:41.315 21639 21639 D Volley  : [1] MarkerLog.finish: (+0   ) [ 1] canceled-at-delivery

Scroll to the right and you notice [ 1] canceled-at-delivery in that last line. This is printed by Volley if upon delivery it notices that the original request has been canceled via cancel(). I had an unfortunate code path that was doing this as a "cleanup action" prematurely leading the request being canceled prior to delivery causing Volley to discard it.

From com.android.volley.ExecutorDelivery:93:

    // If this request has canceled, finish it and don't deliver.
    if (mRequest.isCanceled()) {
        mRequest.finish("canceled-at-delivery");
        return;
    }

Hope this helps.