Fixing #106

src/Microsoft.AspNet.Routing/RouteOptions.cs

@@ -57,6 +57,8 @@ namespace Microsoft.AspNet.Routing
                 // Regex-based constraints
                 { "alpha", typeof(AlphaRouteConstraint) },
                 { "regex", typeof(RegexInlineRouteConstraint) },
+
+                {"required", typeof(RequiredRouteConstraint) },
             };
         }
     }

test/Microsoft.AspNet.Routing.Tests/DefaultInlineConstraintResolverTest.cs

@@ -22,6 +22,17 @@ namespace Microsoft.AspNet.Routing.Tests
             var routeOptions = new RouteOptions();
             _constraintResolver = GetInlineConstraintResolver(routeOptions);
         }
+
+        [Fact]
+        public void ResolveConstraint_RequiredConstraint_ResolvesCorrectly()
+        {
+            // Arrange & Act
+            var constraint = _constraintResolver.ResolveConstraint("required");
+
+            // Assert
+            Assert.IsType<RequiredRouteConstraint>(constraint);
+        }
+
         [Fact]
         public void ResolveConstraint_IntConstraint_ResolvesCorrectly()
         {