Retrofit Uploading multiple images to a single key

Question

I am using Retrofit to upload images to my server. Here I need to upload multiple images for a single key. I have tried with Postman web client it is working well. Here is a screenshot.

Here are the key value pairs for the request.
SurveyImage : [file1,file2,file3];
PropertyImage : file
DRA : jsonBody

I tried to do the same with Retrofit. but the images are not uploading to the server.Here is my code.
WebServicesAPI.java

public interface 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);         JSONObject requestBody = getRequestBody();         RequestBody draBody = null;         try {             draBody = RequestBody.create(MediaType.parse("text/plain"), requestBody.toString(1));             Log.d(TAG, "requestUploadSurvey: RequestBody : " + requestBody.toString(1));         } catch (JSONException e) {             e.printStackTrace();         }         MultipartBody.Builder builder = new MultipartBody.Builder();         builder.setType(MultipartBody.FORM);         MultipartBody surveyImage = null;              for (SurveyModel.PictureModel model : surveyModel.getPicturesList()) {                 File file = new File(model.getImagePath());                 builder.addFormDataPart("SurveyImage", file.getName(),                         RequestBody.create(MediaType.parse("image/*"), file));             }             surveyImage = builder.build();          final WebServicesAPI webServicesAPI = RetrofitManager.getInstance().getRetrofit().create(WebServicesAPI.class);         Call<UploadSurveyResponseModel> surveyResponse = null;              surveyResponse = webServicesAPI.uploadSurvey(MultipartBody.Part.createFormData("SurveyImage", "SurveyImage", surveyImage), propertyImagePart, draBody);          surveyResponse.enqueue(this);          Log.d(TAG, "requestUploadSurvey: sent the request");     } 

Please help me with this.

Answer 1

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); }