Sample Fixture for an owin test server

TestServerFixture.cs

using Microsoft.Owin.Testing;

using System;
using System.Linq;
using System.Net.Http;

using Xunit;

namespace {Your Project}.Tests.Fixtures {
    [CollectionDefinition("Test Server")]
    public class TestServerFixtureCollection : ICollectionFixture<TestServerFixture> {
        // This class has no code, and is never created. Its purpose is simply
        // to be the place to apply [CollectionDefinition] and all the
        // ICollectionFixture<> interfaces.
    }

    public class TestServerFixture : IDisposable {
        bool _disposed = false;

        public TestServer Server { get; private set; }

        public TestServerFixture() {
            Server = TestServer.Create<{your owin startup class here}>();
            Server.BaseAddress = new Uri("https://localhost/");
        }
        ~TestServerFixture() {
            Dispose(false);
        }

        public HttpClient CreateClient() {
            return Server.HttpClient;
        }

        public void Dispose() {
            Dispose(true);
            GC.SuppressFinalize(this);
        }

        protected virtual void Dispose(bool disposing) {
            if (!disposing || _disposed) { return; }

            if (Server != null) {
                Server.Dispose();
                Server = null;
            }

            _disposed = true;
        }
    }
}