Testing ASP.NET Web API Multipart Form Data File upload

Question

I am trying to use N-UNIT to test my web API application but I am unable to find a proper way to test my file upload method. Which would be the best approach to test the method?

Web API Controller:

[AcceptVerbs("post")]
public async Task<HttpResponseMessage> Validate()
    {
        // Check if the request contains multipart/form-data.
        if (!Request.Content.IsMimeMultipartContent())
        {
            return Request.CreateErrorResponse(HttpStatusCode.UnsupportedMediaType,"please submit a valid request");
        }
        var provider = new MultipartMemoryStreamProvider(); // this loads the file into memory for later on processing 
        try
        {
            await Request.Content.ReadAsMultipartAsync(provider);
            var resp = new HttpResponseMessage(HttpStatusCode.OK);
            foreach (var item in provider.Contents)
            {
                if (item.Headers.ContentDisposition.FileName != null)
                {
                    Stream stream = item.ReadAsStreamAsync().Result;
        // do some stuff and return response
                    resp.Content = new StringContent(result, Encoding.UTF8, "application/xml"); //text/plain "application/xml"
                    return resp;
                }
            }
               return resp;
        }
        catch (System.Exception e)
        {
            return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
        }
    }

Answer 1

Based on your above comment, following is an example:

HttpClient client = new HttpClient();

MultipartFormDataContent formDataContent = new MultipartFormDataContent();
formDataContent.Add(new StringContent("Hello World!"),name: "greeting");
StreamContent file1 = new StreamContent(File.OpenRead(@"C:\Images\Image1.jpeg"));
file1.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
file1.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data");
file1.Headers.ContentDisposition.FileName = "Image1.jpeg";
formDataContent.Add(file1);
StreamContent file2 = new StreamContent(File.OpenRead(@"C:\Images\Image2.jpeg"));
file2.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
file2.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data");
file2.Headers.ContentDisposition.FileName = "Image1.jpeg";
formDataContent.Add(file2);

HttpResponseMessage response = client.PostAsync("http://loclhost:9095/api/fileuploads", formDataContent).Result;

---

The request over the wire would like:

POST http://localhost:9095/api/fileuploads HTTP/1.1
Content-Type: multipart/form-data; boundary="34d56c28-919b-42ab-8462-076b400bd03f"
Host: localhost:9095
Content-Length: 486
Expect: 100-continue
Connection: Keep-Alive

--34d56c28-919b-42ab-8462-076b400bd03f
Content-Type: text/plain; charset=utf-8
Content-Disposition: form-data; name=greeting

Hello World!
--34d56c28-919b-42ab-8462-076b400bd03f
Content-Type: image/jpeg
Content-Disposition: form-data; filename=Image1.jpeg

----Your Image here-------
--34d56c28-919b-42ab-8462-076b400bd03f
Content-Type: image/jpeg
Content-Disposition: form-data; filename=Image2.jpeg

----Your Image here-------
--34d56c28-919b-42ab-8462-076b400bd03f--

Answer 2

After spending a bit of time looking into WebClient I was able to come up with this:

     try
        {
            var imageFile = Path.Combine("dir", "fileName");
            WebClient webClient = new WebClient();
            byte[] rawResponse = webClient.UploadFile(string.Format("{0}/api/values/", "http://localhost:12345/"), imageFile);
            Console.WriteLine("Sever Response: {0}", System.Text.Encoding.ASCII.GetString(rawResponse)); // for debugging purposes
            Console.WriteLine("File Upload was successful"); 
        }
        catch (WebException wexc)
        {
           Console.WriteLine("Failed with an exception of " + wexc.Message);  
           // anything other than 200 will trigger the WebException

        }