WebRequest returns 404 when switching to SSL - xamarin

Question

Having built an app using PCL method in Xamarin and have had it working 100% using standard HTTP I now changed the remote test server to use SSL with self signed certs.
The app contacts a custom API for logging onto a server and querying for specific data.
I've changed the app to look at SSL now and initially got an error regarding Authentication not working or something but turned off SSL related errors for testing using:
ServicePointManager.ServerCertificateValidationCallback += (o, certificate, chain, errors) => true;
in my AppDelegate files FinishedLaunching method which got over that error.
I'm now getting a 404 / protocol error when trying to do my Login POST to the given URL.
I am using HttpWebRequest for my RESTful calls and this works fine if I change back to plain http.
Not sure why but some articles suggested using ModernHttpClient, which I did. I imported the component (also added the package using NuGet) to no avail.
Am I missing something else that I should be configuring in my code related to httpwebresponse when contacting the SSL server or is this component simply incapable of speaking to an SSL server?
My login function is as follows (Unrelated code removed/obfuscated):
public JsonUser postLogin(string csrfToken, string partnerId, string username, string password){
string userEndPoint = SingletonAppSettngs.Instance ().apiEndPoint;
userEndPoint = userEndPoint.Replace ("druid/", "");
var request = WebRequest.CreateHttp(string.Format(this.apiBaseUrl + userEndPoint + #"user/login.json"));
// Request header collection set up
request.ContentType = "application/json";
request.Headers.Add ("X-CSRF-Token", csrfToken);
// Add other configs
request.Method = "POST";
using (var streamWriter = new StreamWriter(request.GetRequestStream()))
{
string json_body_content = "{\"username\":\"" + username + "\",\"password\":\"" + password + "\"}";
streamWriter.Write(json_body_content);
streamWriter.Flush();
streamWriter.Close();
}
try{
HttpWebResponse httpResponse = (HttpWebResponse)request.GetResponse();
using (StreamReader reader = new StreamReader (httpResponse.GetResponseStream ())) {
var content = reader.ReadToEnd ();
content = content.Replace ("[],", "null,");
content = content.Replace ("[]", "null");
if (content == null) {
throw new Exception ("request_post_login - content is NULL");
} else {
JsonSerializerSettings jss = new JsonSerializerSettings();
jss.NullValueHandling = NullValueHandling.Ignore;
JsonUser deserializedUser = JsonConvert.DeserializeObject<JsonUser>(content, jss);
if(content.Contains ("Hire company admin user")){
deserializedUser.user.roles.__invalid_name__5 = "Hire company admin user";
deserializedUser.user.roles.__invalid_name__2 = "authenticated user";
}
return deserializedUser;
}
}
}catch(Exception httpEx){
Console.WriteLine ("httpEx Exception: " + httpEx.Message);
Console.WriteLine ("httpEx Inner Exception: " + httpEx.InnerException.Message);
JsonUser JsonUserError = new JsonUser ();
JsonUserError.ErrorMessage = "Error occured: " + httpEx.Message;
return JsonUserError;
}
}

Answer 1

When making a Web Request using ModernHttpClient, I generally follow the pattern below. Another great library created by Paul Betts is refit, and can be used to simplify rest calls.
using (var client = new HttpClient(new NativeMessageHandler(false, false)))
{
client.BaseAddress = new Uri(BaseUrl, UriKind.Absolute);
var result = await Refit.RestService.For<IRestApi>(client).GetData();
}
The second parameter for NativeMessageHandler should be set to true if using a customSSLVerification.
Here's a look at IRestApi
public interface IRestApi
{
[Get("/foo/bar")]
Task<Result> GetMovies();
}

Answer 2

Number of things I had to do to get this to work.
The Self Signed Cert had to allow TLS 1.2
As the API is Drupal based, HTTPS had to be enabled on the server and a module installed to manage the HTTP specific pages.