StringRouteConstraint implementation

src/Microsoft.AspNetCore.Routing/Constraints/StringRouteConstraint.cs

@@ -0,0 +1,67 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Globalization;
+using Microsoft.AspNetCore.Http;
+
+namespace Microsoft.AspNetCore.Routing.Constraints
+{
+    /// <summary>
+    /// Constrains a route parameter to contain only a specified strign.
+    /// </summary>
+    public class StringRouteConstraint : IRouteConstraint
+    {
+        private string _value;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="StringRouteConstraint"/> class.
+        /// </summary>
+        /// <param name="value">The constraint value to match.</param>
+        public StringRouteConstraint(string value)
+        {
+            if (value == null)
+            {
+                throw new ArgumentNullException(nameof(value));
+            }
+
+            _value = value;
+        }
+
+        /// <inheritdoc />
+        public bool Match(HttpContext httpContext, IRouter route, string routeKey, RouteValueDictionary values, RouteDirection routeDirection)
+        {
+            if (httpContext == null)
+            {
+                throw new ArgumentNullException(nameof(httpContext));
+            }
+
+            if (route == null)
+            {
+                throw new ArgumentNullException(nameof(route));
+            }
+
+            if (routeKey == null)
+            {
+                throw new ArgumentNullException(nameof(routeKey));
+            }
+
+            if (values == null)
+            {
+                throw new ArgumentNullException(nameof(values));
+            }
+
+            object routeValue;
+
+            if (values.TryGetValue(routeKey, out routeValue)
+                && routeValue != null)
+            {
+                var parameterValueString = Convert.ToString(routeValue, CultureInfo.InvariantCulture);
+
+                return parameterValueString.Equals(_value, StringComparison.OrdinalIgnoreCase);
+            }
+
+            return false;
+        }
+    }
+}

test/Microsoft.AspNetCore.Routing.Tests/Constraints/StringRouteConstraintTest.cs

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+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Routing.Constraints;
+using Moq;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Routing.Constraints
+{
+    public class StringRouteConstraintTest
+    {
+        [Fact]
+        public void StringRouteConstraintSimpleTrueWithRouteDirectionIncomingRequestTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("home");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "home" });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "controller",
+                values: values,
+                routeDirection: RouteDirection.IncomingRequest);
+
+            // Assert
+            Assert.True(match);
+        }
+
+        [Fact]
+        public void StringRouteConstraintSimpleTrueWithRouteDirectionUrlGenerationTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("home");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "home" });
+
+            var match = constraint.Match(
+              httpContext: Mock.Of<HttpContext>(),
+              route: new Mock<IRouter>().Object,
+              routeKey: "controller",
+              values: values,
+              routeDirection: RouteDirection.UrlGeneration);
+
+            // Assert
+            Assert.True(match);
+        }
+
+        [Fact]
+        public void StringRouteConstraintSimpleFalseWithRouteDirectionIncomingRequestTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("admin");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "home" });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "controller",
+                values: values,
+                routeDirection: RouteDirection.IncomingRequest);
+
+            // Assert
+            Assert.False(match);
+        }
+
+        [Fact]
+        public void StringRouteConstraintSimpleFalseWithRouteDirectionUrlGenerationTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("admin");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "home" });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "controller",
+                values: values,
+                routeDirection: RouteDirection.UrlGeneration);
+
+            // Assert
+            Assert.False(match);
+        }
+
+        [Fact]
+        public void StringRouteConstraintKeyNotFoundWithRouteDirectionIncomingRequestTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("admin");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "admin" });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "action",
+                values: values,
+                routeDirection: RouteDirection.IncomingRequest);
+
+            // Assert
+            Assert.False(match);
+        }
+
+        [Fact]
+        public void StringRouteConstraintKeyNotFoundWithRouteDirectionUrlGenerationTest()
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint("admin");
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = "admin" });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "action",
+                values: values,
+                routeDirection: RouteDirection.UrlGeneration);
+
+            // Assert
+            Assert.False(match);
+        }
+
+        [Theory]
+        [InlineData("User", "uSer", true)]
+        [InlineData("User.Admin", "User.Admin", true)]
+        [InlineData(@"User\Admin", "User\\Admin", true)]
+        [InlineData(null, "user", false)]
+        public void StringRouteConstraintEscapingCaseSensitiveAndRouteNullTest(string routeValue, string constraintValue, bool expected)
+        {
+            // Arrange
+            var constraint = new StringRouteConstraint(constraintValue);
+
+            // Act
+            var values = new RouteValueDictionary(new { controller = routeValue });
+
+            var match = constraint.Match(
+                httpContext: Mock.Of<HttpContext>(),
+                route: new Mock<IRouter>().Object,
+                routeKey: "controller",
+                values: values,
+                routeDirection: RouteDirection.IncomingRequest);
+
+            // Assert
+            Assert.Equal(expected, match);
+        }
+    }
+}