Add WireMock.Net.AspNetCore.Middleware (#1175)

* Add WireMock.Net.AspNetCore.Middleware

* .

* WireMock.Net.Middleware.Tests

* .

* X-WireMock-Response-Delay

src/WireMock.Net.AspNetCore.Middleware/WireMockServerInstance.cs

@@ -0,0 +1,49 @@
+// Copyright © WireMock.Net
+
+using Stef.Validation;
+using WireMock.Server;
+using WireMock.Settings;
+
+namespace WireMock.Net.AspNetCore.Middleware;
+
+/// <summary>
+/// WireMockServer Instance object
+/// </summary>
+internal class WireMockServerInstance
+{
+    private readonly Action<WireMockServer> _configureAction;
+    private readonly WireMockServerSettings? _settings;
+
+    /// <summary>
+    /// Creates a new instance and provides ability to add configuration
+    /// for the start method of <see cref="WireMockServer"/>
+    /// </summary>
+    public WireMockServerInstance(Action<WireMockServer> configure, WireMockServerSettings? settings = null)
+    {
+        _configureAction = Guard.NotNull(configure);
+        _settings = settings;
+    }
+
+    /// <summary>
+    /// Instance accessor for the <see cref="WireMockServer" />
+    /// </summary>
+    public WireMockServer? Instance { get; private set; }
+
+    /// <summary>
+    /// Configures and starts <see cref="WireMockServer"/> instance for use.
+    /// </summary>
+    public void Start()
+    {
+        Instance = _settings != null ? WireMockServer.Start(_settings) : WireMockServer.Start();
+
+        _configureAction.Invoke(Instance);
+    }
+
+    /// <summary>
+    /// Stops the <see cref="WireMockServer"/>
+    /// </summary>
+    public void Stop()
+    {
+        Instance?.Stop();
+    }
+}