Add example for Cors (#712)

* Cors

* Update Program.cs

examples/WireMock.Net.StandAlone.NETCoreApp/Program.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -6,6 +6,8 @@ using System.Threading;
 using log4net;
 using log4net.Config;
 using log4net.Repository;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
 using WireMock.RequestBuilders;
 using WireMock.ResponseBuilders;
 using WireMock.Server;
@@ -33,11 +35,39 @@ namespace WireMock.Net.StandAlone.NETCoreApp
 
             settings.Logger.Debug("WireMock.Net server arguments [{0}]", string.Join(", ", args.Select(a => $"'{a}'")));
 
+            /* https://stackoverflow.com/questions/31942037/how-to-enable-cors-in-asp-net-core */
+            /* Enable Cors */
+            var policyName = "MyPolicy";
+            settings.AdditionalServiceRegistration = services =>
+            {
+                services.AddCors(corsOptions =>
+                    corsOptions.AddPolicy(policyName,
+                        corsPolicyBuilder =>
+                        {
+                            corsPolicyBuilder
+                                .AllowAnyHeader()
+                                .AllowAnyMethod()
+                                .AllowAnyOrigin();
+                        }));
+
+                settings.Logger.Debug("Enable Cors");
+            };
+
+            /* Use Cors */
+            settings.PreWireMockMiddlewareInit = app =>
+            {
+                var appBuilder = (IApplicationBuilder)app;
+                appBuilder.UseCors(policyName);
+
+                settings.Logger.Debug("Use Cors");
+            };
+
             _server = WireMockServer.Start(settings);
 
             _server.Given(Request.Create().WithPath("/api/sap")
                 .UsingPost()
-                .WithBody((IBodyData xmlData) => {
+                .WithBody((IBodyData xmlData) =>
+                {
                     //xmlData is always null
                     return true;
                 }))

src/WireMock.Net/Owin/AspNetCoreSelfHost.cs

@@ -1,6 +1,7 @@
 #if USE_ASPNETCORE
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -8,10 +9,10 @@ using JetBrains.Annotations;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.DependencyInjection;
+using Stef.Validation;
 using WireMock.Logging;
 using WireMock.Owin.Mappers;
 using WireMock.Util;
-using Stef.Validation;
 
 namespace WireMock.Owin
 {
@@ -54,7 +55,7 @@ namespace WireMock.Owin
             // a filesystem handler).
             if (string.IsNullOrEmpty(AppContext.BaseDirectory))
             {
-                builder.UseContentRoot(System.IO.Directory.GetCurrentDirectory());
+                builder.UseContentRoot(Directory.GetCurrentDirectory());
             }
 
             _host = builder

src/WireMock.Net/Owin/OwinSelfHost.cs

@@ -46,10 +46,7 @@ namespace WireMock.Owin
         [PublicAPI]
         public Task StartAsync()
         {
-            return Task.Run(() =>
-            {
-                StartServers();
-            }, _cts.Token);
+            return Task.Run(StartServers, _cts.Token);
         }
 
         [PublicAPI]