Testing ASP.NET Web API Multipart Form Data File upload - unit-testing

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
}