Retrofit: Feature request: multiple file uploading via @Part List<MultipartBody.Part> or @PartMap<String, MultipartBody.Part>

[WesleyWu]

[Feature Request]
Since 2.0.0, setting a filename for an upload file is resolved by OkHttp's MultipartBody.Part,
but the support limited to one file per param via (@Part MultipartBody.Part part).

Multiple file uploading via @PartMap or @Part List<> is still unsupported.

There're two approaches to achieve that.

1) Support @Part List<MultipartBody.Part> as method parameter
When parsing @Part in ServiceMethod.parseParameterAnnotation, allow the parameterizedType of Iterable to be MultipartBody.Part and allow each part setting its OWN headers, instead of setting a common header for all parts.

2) Support @PartMap Map<String, MultipartBody.Part> as method parameter
When parsing @PartMap in ServiceMethod.parseParameterAnnotation, allow the parameterizedType of Iterable to be MultipartBody.Part.
I noticed that, in the code block parsing @PartMap, an exception will be thrown when parameterizedType is detected to be MultipartBody.Part.
The exception message is "@PartMap values cannot be MultipartBody.Part. Use @Part List<Part> or a different value type instead."
Sadly @Part List<Part> is also not supported yet. I supposed it should be @Part List<MultipartBody.Part>.

I prefer to the first approach, because I sometimes need to upload multiple files with same field name (but possibly different filenames), which can't be done with @PartMap unless multimap type support is added.

Thanks.

[JakeWharton]

We meant to include list and array support. Will add. The map makes no sense since the key is redundant with the headers inside the Part.

[anetefr]

Hello,
What is the current solution of uploading dynamic amount of files? I cannot seem to find any. Thx.

[Kolyall]

@anetefr
Example:

List<MultipartBody.Part> parts= new ArrayList();
for (int i = 0; i<5;i++){
 File file = new File(path+i);
part = MultipartBody.Part.createFormData("file"+i, file.getName(), RequestBody.create(MediaType.parse("image/*"), file));
parts.add(part);
}
uploadFileObservable(url/*yourUrl*/,parts).subscribe(action/*anyAction*/);

  @Multipart
    @POST
    Observable<Void> uploadFilesObservable(@Url String url, @Part List<MultipartBody.Part> parts);

[sahildoshi013]

@Kolyall
What is PHP Code for get that "@Part List parts"?

[snetts]

@Kolyall Could you please post the full code for the benefit of us newbies. I am using an adapter and it cannot resolve the symbol path and part. Here is my code:

FilesUploadService filesUploadService = mApiService.RootService(FilesUploadService.class, EndPoints.BACKEND_BASE_URL); Call<FilesResponse> filesResponseCall; int messageId = messagesModel.getId();

        `List<MultipartBody.Part> parts= new ArrayList();
        for (int i = 0; i<5;i++){
            File file = new File(path+i);
            part = MultipartBody.Part.createFormData("file"+i, file.getName(), RequestBody.create(MediaType.parse("image/*"), file));
            parts.add(part);
        }

        filesResponseCall = filesUploadService.uploadMessageImages(List<Uri> parts);

`
Any help will be highly appreaciated.