Multipart Retrofit 2.0 image upload

2
votes

I am trying to upload image by POST multipart request which should have structure like this :

-----------------------------219391268715340 Content-Disposition: form-data; name="photos[]"; filename="DSCF0157-Laptop.JPG" Content-Type: image/jpeg

(byte-data)

My code :

        MediaType mediaType = MediaType.parse("image/jpeg");
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream);
        byte[] byteArray = stream.toByteArray();

        RequestBody file=RequestBody.create(mediaType, byteArray);
        map.put("form-data; name=\"photos[]\"; filename=\""+filename+".jpg",file);

I use map because of @PartMap annotation - I want to upload multiple files. My server returns http code 200 - but no files are uploaded. Api call has been tested - it works correctly if used by our web application. Any idea what I am doing wrong

2
androidapiretrofitretrofit2

2 Answers

2
votes

If you want to upload many files in a request using Retrofit 2, you can refer to my answer at the question below

Retrofit - Multipart request: Required MultipartFile parameter 'file' is not present

With some modifications:

WebAPIService.java:

@Multipart
@POST("/api/fileupload")
Call<ResponseBody> postFiles(@Part List<MultipartBody.Part> fileList);

FileActivity.java:

...
List<MultipartBody.Part> fileList = new ArrayList<>();
for (int i = 0; i < 2; i++){
    fileList.add(body);

}
Call<ResponseBody> call = service.postFiles(fileList);
call.enqueue(new Callback<ResponseBody>() {
    @Override
    public void onResponse(Call<ResponseBody> call,
                           Response<ResponseBody> response) {
        Log.i(LOG_TAG, "success");
    }

    @Override
    public void onFailure(Call<ResponseBody> call, Throwable t) {
        Log.e(LOG_TAG, t.getMessage());
    }
});

Of course, with the above code, in fact, the same file (body) will be uploaded as 2 parts in the request. As a result, in web server, you will have 2 files with the same content, you can customize the fileList with many different files :)

Hope it helps!

0
votes

Maybe you can do that like this.

YourAPIService

@Multipart
@POST("api/image/upload")
Call<ImageUploadResponse> uploadImage(@Part("photos") List<RequestBody> imageFiles);

YourActivity 

//prepare request body
List<RequestBody> images = new ArrayList<>();
for (int i = 0; i < filePath.size(); i++){
RequestBody file = RequestBody.create(MediaType.parse("image/*"), filePath.get(i);
   images.add(file);
}

//call api
Call<ImageUploadResponse> call = imageUploadService.uploadImage(images);
  call.enqueue(new Callback<ImageUploadResponse>() {
      @Override
     public void onResponse(Call<ImageUploadResponse> call,
                         Response<ImageUploadResponse> response) {

     }

     @Override
     public void onFailure(Call<ImageUploadResponse> call, Throwable t) {

     }
});