SELF HOST: Support weak and strong wildcards in URL prefixes

src/Nancy.Hosting.Self/HostConfiguration.cs

@@ -17,6 +17,16 @@ public sealed class HostConfiguration
         /// </summary>
         public bool RewriteLocalhost { get; set; }
 
+        /// <summary>
+        /// Gets or sets a property indicating that <see cref="RewriteLocalhost"/>
+        /// should use the weak wildcard (*) instead of the strong wildcard (+).
+        /// If you use the weak wildcard then Nancy will only receive requests that
+        /// have not matched any other URL prefix registration, in other words
+        /// requests that no other application wants to handle.
+        /// Defaults to false.
+        /// </summary>
+        public bool UseWeakWildcard { get; set; }
+
         /// <summary>
         /// Configuration around automatically creating URL reservations.
         /// </summary>
@@ -98,6 +108,7 @@ private static int ProcessorThreadCount
         public HostConfiguration()
         {
             this.RewriteLocalhost = true;
+            this.UseWeakWildcard = false;
             this.UrlReservations = new UrlReservations();
             this.AllowChunkedEncoding = true;
             this.UnhandledExceptionCallback = e =>

src/Nancy.Hosting.Self/NancyHost.cs

@@ -241,7 +241,7 @@ internal IEnumerable<string> GetPrefixes()
 
                 if (this.configuration.RewriteLocalhost && !baseUri.Host.Contains("."))
                 {
-                    prefix = prefix.Replace("localhost", "+");
+                    prefix = prefix.Replace("localhost", this.configuration.UseWeakWildcard ? "*" : "+");
                 }
 
                 yield return prefix;

test/Nancy.Hosting.Self.Tests/NancySelfHostFixture.cs

@@ -248,6 +248,58 @@ public void Should_include_default_port_in_uri_prefixes()
             prefix.ShouldEqual("http://+:80/");
         }
 
+        [Fact]
+        public void Should_use_strong_wildcard_in_url_prefixes_by_default()
+        {
+            // Given
+            var host = new NancyHost(
+                new HostConfiguration(),
+                new Uri("http://localhost/")
+            );
+
+            // When
+            var prefix = host.GetPrefixes().Single();
+
+            // Then
+            prefix.ShouldStartWith("http://+:");
+        }
+
+        [Fact]
+        public void Should_use_strong_wildcard_in_url_prefixes_when_configured()
+        {
+            // Given
+            var host = new NancyHost(
+                new HostConfiguration() {
+                    UseWeakWildcard = false,
+                },
+                new Uri("http://localhost/")
+            );
+
+            // When
+            var prefix = host.GetPrefixes().Single();
+
+            // Then
+            prefix.ShouldStartWith("http://+:");
+        }
+
+        [Fact]
+        public void Should_use_weak_wildcard_in_url_prefixes_when_configured()
+        {
+            // Given
+            var host = new NancyHost(
+                new HostConfiguration() {
+                    UseWeakWildcard = true,
+                },
+                new Uri("http://localhost/")
+            );
+
+            // When
+            var prefix = host.GetPrefixes().Single();
+
+            // Then
+            prefix.ShouldStartWith("http://*:");
+        }
+
         [Fact]
         public void Should_not_throw_when_disposed_without_starting()
         {