c# httpwebrequest getResponse() freezes and hangs my program

Question

I was trying to use httpwebrequest to use a rest like service on a remote server and from the first execution itself, my code was hanging the program. Then I tried it as a console application to make sure it has nothing to do with the program itself but no luck!

        string credentialsJson = @"{""username"":""test"",
                                      ""password"":""test"" 
                                   }";

        int tmp = ServicePointManager.DefaultConnectionLimit;
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(@"https://qrua.com/qr/service" + @"/auth/login");
        request.Method = "POST";
        request.KeepAlive = true;
        request.Timeout = 50000 ;
        request.CookieContainer = new CookieContainer();
        request.ContentType = "application/json";
        try
        {
            StreamWriter writer = new StreamWriter(request.GetRequestStream());
            writer.Write(credentialsJson);
        }
        catch (Exception e)
        {
            Console.WriteLine("EXCEPTION:" + e.Message);
        }

        //WebResponse response = request.GetResponse();
        try
        {
            using (WebResponse response = (HttpWebResponse)request.GetResponse())
            {
                Console.WriteLine("request:\n" + request.ToString() + "\nresponse:\n" + response.ContentLength);
                response.Close();
            }
        }
        catch (Exception e)
        {
            Console.WriteLine("EXCEPTION: in sending http request:" + " \nError message:" + e.Message);
        }

Tried several things from different forums but it doesnt help. Even a simple console app with the above code hangs the console indefinitely! Any help would be great..

Thanks

Exploit

Try specifying request.ContentLength. See: stackoverflow.com/questions/6736056 – Followup

Answer 1

You're never closing the StreamWriter... so I suspect it's not being flushed. Admittedly I'd expect an error from the server instead of just a hang, but it's worth looking at.

Btw, you don't need to close the response and dispose it. Just the using statement is enough.

Britannia

Why did you mark this as correct, and then in another place you say, "tried closing the writer and it didnt do much" ? – Followup

@Lost Hobbit: I suggest you add a comment to the question instead of to my answer - the OP won't get notification of this comment. (Not that the OP has been on Stack Overflow for 11 months anyway...) – Britannia

Was using HtmlAgilityPack and following permanent redirects in that library didnt close the underlying response before creating a new. – Willette

This exactly worked for me on the exact problem I was just having. Thanks @JonSkeet. – Ivoryivorywhite

Helped me a lot. Thanks. – Elgon

Answer 2

There's not much you can do if the remote server is not responding other than defining a Timeout and catch the exception as you did in order to inform the user that the operation cannot complete because the remote site didn't respond:

var request = (HttpWebRequest)WebRequest.Create("https://qrua.com/qr/service/auth/login");
request.Timeout = 5000;
// If the server doesn't respond within 5 seconds you might catch the timeout exception
using (var response = request.GetResponse())
{

}

If you don't want to freeze the UI you could use the async version: BeginGetResponse

Hydrogeology

Answer 3

Try specifying request.ContentLength.

Before doing:

        StreamWriter writer = new StreamWriter(request.GetRequestStream());
        writer.Write(credentialsJson);

Try something like this:

using (MemoryStream stream = new MemoryStream())
{
    using (var writer = StreamWriter writer = new StreamWriter(stream))
    {
        writer.Write(credentialsJson);
        writer.Close();
    }
    request.ContentLength = stream.Length;
}

Followup