HttpClient fails to respond after a period of time

Question

I have a Asp.Net Core (2.1) website using Asp.Net Boilerplate.

I'm trying to make a API call using HttpClient, which works locally, but throws an error when deployed to IIS.

I created a TypedClient

public class FormsHttpClient : IFormsHttpClient
{
    private const string url = "my_url:3001/";
    private readonly HttpClient _client;

    public FormsHttpClient(HttpClient httpClient)
    {
        httpClient.BaseAddress = new Uri(url);

        _client = httpClient;
    }
    ....
}

In my startup.cs file, I added:

services.AddHttpClient<IFormsHttpClient, FormsHttpClient>();

The error i get when i deploy:

ERROR 2018-12-12 18:30:29,509 [11 ] Mvc.ExceptionHandling.AbpExceptionFilter - A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond System.Net.Http.HttpRequestException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond at System.Net.Http.ConnectHelper.ConnectAsync(String host, Int32 port, CancellationToken cancellationToken) --- End of inner exception stack trace ---

The network call normally takes 1800ms to finish, it seems to timeout around 21000ms.

I came across the code AppContext.SetSwitch("System.Net.Http.useSocketsHttpHandler", false);, thought i wasn't sure where to put it, i tossed it in the constructor of my startup.cs class but it doesn't seem to have any effect.

Is there something else im missing?

E: The code that calls the api is in JS:

   app.forms.token = {
    generate: function () {
        Formio.logout();
        abp.services.app.forms.generateFormToken().done(function (e) {
            Formio.setToken(e);
        });
    },
    clear: function () {
        Formio.logout();
    }
}

Where are you making the request?! This is just registering service... — Kos
If it works locally, then your code is fine. Are you sure you can actually reach that web service (my_url:3001) from the server you deployed this to? — Gabriel Luci
@kos making the request in JS, the call returns 500 @gabriel, i can make the same api call in postman from the same device, so i can definitely access it. It seems the be the failing on any HttpClient's PostAsync or GetAsync, depending on which call i make — lizzy91
That might be issue with that my_url:3001 service. In production you are requesting something that make it die. I would try to use some tool to capture the request like fiddler to investigate furder... — Kos
@Kos thanks. I figured out a work around which is probably a good solution of its own. I had to change the IP to an internal IP (10.200.x.xx) for my server code and keep using the public IP in client side code. I was basically trying to access the same server on a different port. learning is fun =D — lizzy91

lizzy91 lizzy91 · Accepted Answer · 2018-12-26T17:15:34

Since I am communicating with the same machine but different port, I changed the public IP in my server code to an internal IP and my problem was resolved.

I've made it a rule of thumb to use internal IP in server code and public IP in client code. If this is bad practice, let me know.

HttpClient fails to respond after a period of time

1 Answers