Retrofit Uploading multiple images to a single key

We can use MultipartBody.Part array to upload an array of images to a single key.
Here is the solution
WebServicesAPI

@Multipart
@POST(WebServices.UPLOAD_SURVEY)
Call<UploadSurveyResponseModel> uploadSurvey(@Part MultipartBody.Part[] surveyImage,
                                             @Part MultipartBody.Part propertyImage,
                                             @Part("DRA") RequestBody dra);

Here is the method for uploading the files.

private void requestUploadSurvey () {
    File propertyImageFile = new File(surveyModel.getPropertyImagePath());
    RequestBody propertyImage = RequestBody.create(MediaType.parse("image/*"),
                                                   propertyImageFile);
    MultipartBody.Part propertyImagePart = MultipartBody.Part.createFormData("PropertyImage",
                                                                             propertyImageFile.getName(),
                                                                             propertyImage);

    MultipartBody.Part[] surveyImagesParts = new MultipartBody.Part[surveyModel.getPicturesList()
                                                                               .size()];

    for (int index = 0; index <
                        surveyModel.getPicturesList()
                                   .size(); index++) {
        Log.d(TAG,
              "requestUploadSurvey: survey image " +
              index +
              "  " +
              surveyModel.getPicturesList()
                         .get(index)
                         .getImagePath());
        File file = new File(surveyModel.getPicturesList()
                                        .get(index)
                                        .getImagePath());
        RequestBody surveyBody = RequestBody.create(MediaType.parse("image/*"),
                                                    file);
        surveyImagesParts[index] = MultipartBody.Part.createFormData("SurveyImage",
                                                                     file.getName(),
                                                                     surveyBody);
    }

    final WebServicesAPI webServicesAPI = RetrofitManager.getInstance()
                                                         .getRetrofit()
                                                         .create(WebServicesAPI.class);
    Call<UploadSurveyResponseModel> surveyResponse = null;
    if (surveyImagesParts != null) {
        surveyResponse = webServicesAPI.uploadSurvey(surveyImagesParts,
                                                     propertyImagePart,
                                                     draBody);
    }
    surveyResponse.enqueue(this);
}