scadaproj/ZB.MOM.WW.Overview/tests/ZB.MOM.WW.Overview.Tests/ProbeRedirectTests.cs

using System.Net;
using Microsoft.Extensions.DependencyInjection;
using ZB.MOM.WW.Overview.Polling;

namespace ZB.MOM.WW.Overview.Tests;

/// <summary>Overview-003: the pooled probe client must not follow redirects.</summary>
public sealed class ProbeRedirectTests
{
    [Fact]
    public async Task ActiveProbe_AuthRedirectToLoginPage_IsNotReportedAsActive()
    {
        var port = FreePort();
        var prefix = $"http://127.0.0.1:{port}/";
        using var listener = new HttpListener();
        listener.Prefixes.Add(prefix);
        listener.Start();
        var server = Task.Run(async () =>
        {
            while (listener.IsListening)
            {
                HttpListenerContext ctx;
                try { ctx = await listener.GetContextAsync(); } catch { return; }
                if (ctx.Request.Url!.AbsolutePath == "/login")
                {
                    ctx.Response.StatusCode = 200;
                    ctx.Response.ContentType = "text/html";
                    await ctx.Response.OutputStream.WriteAsync("<html>login</html>"u8.ToArray());
                }
                else
                {
                    ctx.Response.StatusCode = 302;
                    ctx.Response.RedirectLocation = "/login";
                }
                ctx.Response.Close();
            }
        });

        var services = new ServiceCollection();
        services.AddLogging();
        services.AddOverviewPolling();
        await using var provider = services.BuildServiceProvider();
        var client = provider.GetRequiredService<IHttpClientFactory>().CreateClient(OverviewPollerService.HttpClientName);

        var probe = await new ZbHealthReportClient(client)
            .ProbeStatusAsync($"{prefix}health/active", TimeSpan.FromSeconds(5));

        listener.Stop();
        Assert.Equal(302, probe.StatusCode);
        Assert.Equal(ActiveState.Unknown, StatusDerivation.ObserveActive(true, probe));
    }

    private static int FreePort()
    {
        var l = new System.Net.Sockets.TcpListener(IPAddress.Loopback, 0);
        l.Start();
        var port = ((IPEndPoint)l.LocalEndpoint).Port;
        l.Stop();
        return port;
    }
}