Is it possible pause & resume for Retrofit multipart request?

Question

We are using Retrofit multi-part for file uploading process.

We want pause/resume when file uploading.

I want to know its possible or not?

Code for multi-part file upload

  RequestBody requestFile =
            RequestBody.create(MediaType.parse("multipart/form-data"), file);

  // MultipartBody.Part is used to send also the actual file name
  MultipartBody.Part body =MultipartBody.Part.createFormData("image", file.getName(), requestFile);
  Call<ResponseBody> call= api.uploadFile(body);

Please read [ask] for tips on how to improve your question. In particular, "is it possible" is not specific enough for this site. — Code-Apprentice, Jul 18 '18 at 16:54
@Code-Apprentice I clearly asked specific question. Its not broad question & I don't ask tutorial or code something. — Ranjithkumar, Jul 18 '18 at 16:58
You can look at this :https://cloud.google.com/storage/docs/json_api/v1/how-tos/resumable-upload — Lalit Jadav, Jul 26 '18 at 13:13
This might help https://stackoverflow.com/a/49364158/7123413 — RoyalGriffin, Jul 30 '18 at 10:10

aanshu · Answer 1 · 2018-07-31T03:21:28.177

8

Yes its possible. You would have to create your own request body.

   public class PausableRequestBody extends RequestBody {
    private static final int BUFFER_SIZE = 2048;
    private File mFile;
    private long uploadedData;

    public PausableRequestBody(final File file) {
        mFile = file;
    }

    @Override
    public MediaType contentType() {
        return MediaType.parse("image/*");
    }

    @Override
    public long contentLength() throws IOException {
        return mFile.length();
    }

    @Override
    public void writeTo(BufferedSink bs) throws IOException {
        long fileLength = mFile.length();
        byte[] buffer = new byte[BUFFER_SIZE];
        FileInputStream in = new FileInputStream(mFile);

        try {
            int read;
            while ((read = in.read(buffer)) != -1) {
                this.uploadedData += read;
                bs.write(buffer, 0, read);
            }
        } finally {
            in.close();
        }
    }

    public long getUploadedData() {
        return uploadedData;
    }
}

use append instead of write..

Use following Retrofit call

PausableRequestBody fileBody = new PausableRequestBody(file, this);
        MultipartBody.Part filePart = MultipartBody.Part.createFormData("image", file.getName(), fileBody);

        Call<JsonObject> request = RetrofitClient.uploadImage(filepart);
        request.enqueue(new Callback<JsonObject>{...});

to pause the request you would have to cancel the call request.cancel()

to restart use the same PausableRequestBody object with the same method mentioned above

edited Jul 31 '18 at 03:21

answered Jul 30 '18 at 07:49

aanshu

1,602
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1

Where is pause request? – Ranjithkumar Jul 30 '18 at 09:14
to pause you need to cancel the request mentioned above. – aanshu Jul 30 '18 at 11:12
1

If I restart it will start from first or paused position? – Ranjithkumar Jul 30 '18 at 11:14
for that you need to append instead of write. – aanshu Jul 30 '18 at 11:18
did it helped.? – aanshu Jul 30 '18 at 12:05
sry to say! I am not understand where I need to append instead off write. – Ranjithkumar Jul 30 '18 at 12:18
If I give bs.append() -> it will continue from paused position? unbelievable.. I will offer you bounty.. can you give detailed answer. I hope it looks working solution – Ranjithkumar Jul 30 '18 at 12:29
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/177026/discussion-between-kunal-mahajan-and-ranjith-kumar). – aanshu Jul 30 '18 at 12:47
Hey, sorry dear, I thought you found a solution. Will that be possible to share your code, I will work on it. ? – aanshu Aug 07 '18 at 06:37
ok bro. when you free only give me the answer. no need to stop/hold your work – Ranjithkumar Aug 07 '18 at 06:39
thank you @Ranjith, you are awesome. In mean if possible share your code either on github here. – aanshu Aug 07 '18 at 07:30

Navneet Krishna · Answer 2 · 2018-07-25T10:26:38.493

As suggested by Jake Wharton from Square,

There is no built-in pause or resume for retrofit.

If you want to stick on to retrofit then you may need to make your backend to support range requests. This can help you to break the connection at any time during a streaming download. You can then use the range headers in every subsequent requests to support pause or resume download.

You may also check this answer using using okhttp

Is it possible pause & resume for Retrofit multipart request?

2 Answers2