[dotnet] Handle unsuccessful http requests properly

[nvborisenko]

• Check http status code
• Removed code which is never executed

I didn't verify whether the solution is still compiling without errors, I wrote this code in notepad.

Fixes #10805

[titusfortner]

Thanks for the PR.

I'm still learning the .NET classes. Why can't that code you deleted be executed? Thanks.

[nvborisenko]

In version 4 selenium was migrated from WebRequest to new HttpClient, what is good. But HttpClient works slightly differently.

For instance timeout exception now looks like this:
in .net 6

Unhandled exception. System.Threading.Tasks.TaskCanceledException: The request was canceled due to the configured HttpClient.Timeout of 0.001 seconds elapsing.
 ---> System.TimeoutException: A task was canceled.
 ---> System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at System.Threading.Tasks.TaskCompletionSourceWithCancellation`1.WaitWithCancellation(CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.GetHttp11ConnectionAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.SendWithVersionDetectionAndRetryAsync(HttpRequestMessage request, Boolean async, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.HttpMessageHandlerStage.Send(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.DiagnosticsHandler.SendAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)

in .net framework 4.8

Unhandled Exception: System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)

Or if cannot connect to the server:
in .net 6

Unhandled exception. System.Net.Http.HttpRequestException: No such host is known. (werkjhwberkjbwkerwe876.com:443)
 ---> System.Net.Sockets.SocketException (11001): No such host is known.
   at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ThrowException(SocketError error, CancellationToken cancellationToken)

in .net framework 4.8

Unhandled Exception: System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The remote name could not be resolved: 'werkjhwberkjbwkerwe876.com'


   at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
   at System.Net.Http.HttpClientHandler.GetResponseCallback(IAsyncResult ar)

[titusfortner]

Your fix won't work because there are lots of unsuccessful status codes that are valid: https://w3c.github.io/webdriver/#errors

[titusfortner]

Ah, I see what is going on. Sauce Labs returns a different signature than Browser Stack, which is why it isn't having the same issue for a 401 error.

The issue is when this condition isn't met in CreateResponse():

      if (responseInfo.ContentType != null && responseInfo.ContentType.StartsWith("application/json", StringComparison.OrdinalIgnoreCase))

Since all valid webdriver responses have to be those things, this is going to apply when either the http response isn't coming from a driver/server (i.e. bad request in StartSession()), or is an invalid webdriver response.

I think what we want to do is throw a WebDriverException from an else if after the previous one like

new HttpResponseMessage(responseInfo.StatusCode).IsSuccessStatusCode

[nvborisenko]

It was hard to understand, and finally it works for me.

I didn't touch or changed logic in making http requests, generally, don't throw any exceptions.

Current Logic:
When we get http response, we construct Response based on body. Status of response is also set based on json body. But body might be formatted unexpectedly.

What I did:
After constructing Response object based on json body, we also set Status based on http status in case if we couldn't parse status from body (Success by default). So setting proper Status here allows it to be handled later and throw corresponding exception like NoSuchElementException.

@titusfortner thanks for your suggestion and please review.