Drupal 7 Service module node resources attach_file end point - xamarin

Question

I am implementing a Xamarin Form mobile app to allow post photo to Drupal using service module node resources. http://xxxx.com/{endpoint}/node/4/attach_file
i able to post from POSTMAN with
I tried to implement with c# HttpClient but keep getting response like "401 :Missing required argument field_name"
Please help on my code:
var httpClient = new HttpClient(new NativeMessageHandler());
httpClient.Timeout.Add(new TimeSpan(0, 0, 30));
httpClient.BaseAddress = new Uri(BaseAddress);
var content = new MultipartFormDataContent();
var streamContent = new StreamContent(g_media.GetStream());
streamContent.Headers.ContentDisposition = ContentDispositionHeaderValue.Parse("form-data");
streamContent.Headers.ContentDisposition.Parameters.Add(new NameValueHeaderValue("field_name", "field_receipt_image"));
content.Add(streamContent,"files[file]");
var response = await httpClient.PostAsync("node/4/attach_file", content);
response.EnsureSuccessStatusCode();

Answer 1

I had the same issue and used RestSharp to resolve it. Here is the code I used to upload a file to Drupal:
var restClient = new RestClient("http:XXXXXX/attach_file");
var request = new RestRequest(Method.POST);
request.AddFile("files[file]", fileName);
request.AddParameter("field_name", field);
IRestResponse response = restClient.Execute(request);