Upload file with retrofit

UploadFileWithRetrofit.kt

// Activity
    val file = File(path)
    val requestFile = RequestBody.create(MediaType.parse(context.contentResolver.getType(data.data)), file)
    val body = MultipartBody.Part.createFormData("avatar", file.name, requestFile)
    presenter.uploadUserAvatar(body)
// Activity

// Endpoint.kt
    @Multipart
    @POST(Const.URL.USER_AVATAR_UPDATE)
    fun uploadAvatar( @Part file: MultipartBody.Part): Observable<GetAvatarModel>
// Endpoint.kt