Fuel download returns empty bytes?

Question

I'm using Fuel library for Kotlin to download an image.

The following code works as far as showing the download status ... but, the Log.e("fetchProfileImage", "bytes --> ${bytes.size}") line yields "0" for byte size, so I'm confused as to what's going on.

Is this the expected behavior, or am I doing something wrong?

        Fuel.download(endpoint).destination { response, url ->
            File.createTempFile("profileImage", ".jpg")
        }.progress { readBytes, totalBytes ->
            val fractionCompleted = readBytes.toFloat() / totalBytes.toFloat()
            this.delegate?.downloadProgressDidChange(to = fractionCompleted)
        }.response { request, response, result ->
            val (data, error) = result
            if (error != null) {
                Log.e("fetchProfileImage", "error: ${error}")
            } else {
                result.fold({ bytes ->

                    Log.e("fetchProfileImage", "bytes --> ${bytes.size}")
                    // delegate?.didReceiveProfileImage(bmp)
                }, {err ->
                    Log.e("fetchProfileImage", "error: ${err}")
                })
            }
        }

Here's the response:

Response : OK 
Length : 426828
Body : (426828 bytes of image/jpeg)
Headers : (8)
Content-Length : [426828]
Content-Type : [image/jpeg]
Date : [Mon, 12 Feb 2018 04:10:27 GMT]
Server : [Jetty(9.4.3.v20170317)]
X-Android-Received-Millis : [1518408627531]
X-Android-Response-Source : [NETWORK 200]
X-Android-Selected-Protocol : [http/1.1]
X-Android-Sent-Millis : [1518408627121]

Answer 1

This is a problem with the internal workings of Fuel

I have raised a pr that fixes this issue (in a suitable manner I hope) https://github.com/kittinunf/Fuel/issues/275

This is not something you as a user have done wrong