InputStreamRequestBody https://github.com/square/okhttp/issues/3585

Okhttp InputStream

public class InputStreamRequestBody extends RequestBody {
    private final MediaType contentType;
    private final ContentResolver contentResolver;
    private final Uri uri;

    public InputStreamRequestBody(MediaType contentType, ContentResolver contentResolver, Uri uri) {
        if (uri == null) throw new NullPointerException("uri == null");
        this.contentType = contentType;
        this.contentResolver = contentResolver;
        this.uri = uri;
    }

    @Nullable
    @Override
    public MediaType contentType() {
        return contentType;
    }

    @Override
    public long contentLength() throws IOException {
        return -1;
    }

    @Override
    public void writeTo(@NonNull BufferedSink sink) throws IOException {
        try (Source source = Okio.source(contentResolver.openInputStream(uri))) {
          sink.writeAll(source);
        }
    }
}