Merge pull request #803 from dotnet-maestro-bot/merge/release/2.2-to-master

[automated] Merge branch 'release/2.2' => 'master'

src/Microsoft.AspNetCore.Routing.Abstractions/IOutboundParameterTransformer.cs

@@ -4,15 +4,16 @@
 namespace Microsoft.AspNetCore.Routing
 {
     /// <summary>
-    /// Defines the contract that a class must implement to transform parameter values.
+    /// Defines the contract that a class must implement to transform route values while building
+    /// a URI.
     /// </summary>
-    public interface IParameterTransformer : IParameterPolicy
+    public interface IOutboundParameterTransformer : IParameterPolicy
     {
         /// <summary>
-        /// Transforms the specified parameter value.
+        /// Transforms the specified route value to a string for inclusion in a URI.
         /// </summary>
-        /// <param name="value">The parameter value to transform.</param>
+        /// <param name="value">The route value to transform.</param>
         /// <returns>The transformed value.</returns>
-        string Transform(string value);
+        string TransformOutbound(object value);
     }
 }

src/Microsoft.AspNetCore.Routing/DefaultLinkGenerator.cs

@@ -280,13 +280,40 @@ namespace Microsoft.AspNetCore.Routing
 
         private TemplateBinder CreateTemplateBinder(RouteEndpoint endpoint)
         {
+            // Now create the constraints and parameter transformers from the pattern
+            var policies = new List<(string parameterName, IParameterPolicy policy)>();
+            foreach (var kvp in endpoint.RoutePattern.ParameterPolicies)
+            {
+                var parameterName = kvp.Key;
+
+                // It's possible that we don't have an actual route parameter, we need to support that case.
+                var parameter = endpoint.RoutePattern.GetParameter(parameterName);
+
+                // Use the first parameter transformer per parameter
+                var foundTransformer = false;
+                for (var i = 0; i < kvp.Value.Count; i++)
+                {
+                    var parameterPolicy = _parameterPolicyFactory.Create(parameter, kvp.Value[i]);
+                    if (!foundTransformer && parameterPolicy is IOutboundParameterTransformer parameterTransformer)
+                    {
+                        policies.Add((parameterName, parameterTransformer));
+                        foundTransformer = true;
+                    }
+
+                    if (parameterPolicy is IRouteConstraint constraint)
+                    {
+                        policies.Add((parameterName, constraint));
+                    }
+                }
+            }
+
             return new TemplateBinder(
                 UrlEncoder.Default,
                 _uriBuildingContextPool,
                 endpoint.RoutePattern,
                 new RouteValueDictionary(endpoint.RoutePattern.Defaults),
                 endpoint.Metadata.GetMetadata<IRouteValuesAddressMetadata>()?.RequiredValues.Keys,
-                _parameterPolicyFactory);
+                policies);
         }
 
         // Internal for testing
@@ -312,11 +339,10 @@ namespace Microsoft.AspNetCore.Routing
                 return false;
             }
 
-            if (!MatchesConstraints(httpContext, endpoint, templateValuesResult.CombinedValues))
+            if (!templateBinder.TryProcessConstraints(httpContext, templateValuesResult.CombinedValues, out var parameterName, out var constraint))
             {
                 result = default;
-
+                Log.TemplateFailedConstraint(_logger, endpoint, parameterName, constraint, templateValuesResult.CombinedValues);
-                // MatchesConstraints does its own logging, so we're not logging here.
                 return false;
             }
 
@@ -330,36 +356,6 @@ namespace Microsoft.AspNetCore.Routing
             return true;
         }
 
-        private bool MatchesConstraints(
-            HttpContext httpContext,
-            RouteEndpoint endpoint,
-            RouteValueDictionary routeValues)
-        {
-            if (routeValues == null)
-            {
-                throw new ArgumentNullException(nameof(routeValues));
-            }
-
-            foreach (var kvp in endpoint.RoutePattern.ParameterPolicies)
-            {
-                var parameter = endpoint.RoutePattern.GetParameter(kvp.Key); // may be null, that's ok
-                var constraintReferences = kvp.Value;
-                for (var i = 0; i < constraintReferences.Count; i++)
-                {
-                    var constraintReference = constraintReferences[i];
-                    var parameterPolicy = _parameterPolicyFactory.Create(parameter, constraintReference);
-                    if (parameterPolicy is IRouteConstraint routeConstraint
-                        && !routeConstraint.Match(httpContext, NullRouter.Instance, kvp.Key, routeValues, RouteDirection.UrlGeneration))
-                    {
-                        Log.TemplateFailedConstraint(_logger, endpoint, kvp.Key, routeConstraint, routeValues);
-                        return false;
-                    }
-                }
-            }
-
-            return true;
-        }
-
         // Also called from DefaultLinkGenerationTemplate
         public static RouteValueDictionary GetAmbientValues(HttpContext httpContext)
         {

src/Microsoft.AspNetCore.Routing/Internal/UriBuildingContext.cs

@@ -56,10 +56,10 @@ namespace Microsoft.AspNetCore.Routing.Internal
 
         public bool Accept(string value)
         {
-            return Accept(value, encodeSlashes: true, parameterTransformer: null);
+            return Accept(value, encodeSlashes: true);
         }
 
-        public bool Accept(string value, bool encodeSlashes, IParameterTransformer parameterTransformer)
+        public bool Accept(string value, bool encodeSlashes)
         {
             if (string.IsNullOrEmpty(value))
             {
@@ -80,31 +80,31 @@ namespace Microsoft.AspNetCore.Routing.Internal
                 return false;
             }
 
-            // NOTE: call the parameter transformer before changing the case
-            // A transformer might use the case, e.g. AllProducts -> all-products
-            if (parameterTransformer != null)
-            {
-                value = parameterTransformer.Transform(value);
-            }
-
             // NOTE: this needs to be above all 'EncodeValue' and _path.Append calls
             if (LowercaseUrls)
             {
                 value = value.ToLowerInvariant();
             }
 
-            for (var i = 0; i < _buffer.Count; i++)
+            var buffer = _buffer;
+            for (var i = 0; i < buffer.Count; i++)
             {
-                if (_buffer[i].RequiresEncoding)
+                var bufferValue = buffer[i].Value;
+                if (LowercaseUrls)
                 {
-                    EncodeValue(_buffer[i].Value);
+                    bufferValue = bufferValue.ToLowerInvariant();
+                }
+
+                if (buffer[i].RequiresEncoding)
+                {
+                    EncodeValue(bufferValue);
                 }
                 else
                 {
-                    _path.Append(_buffer[i].Value);
+                    _path.Append(bufferValue);
                 }
             }
-            _buffer.Clear();
+            buffer.Clear();
 
             if (UriState == SegmentState.Beginning && BufferState == SegmentState.Beginning)
             {

src/Microsoft.AspNetCore.Routing/Template/TemplateBinder.cs

@@ -20,10 +20,11 @@ namespace Microsoft.AspNetCore.Routing.Template
     {
         private readonly UrlEncoder _urlEncoder;
         private readonly ObjectPool<UriBuildingContext> _pool;
-        private readonly ParameterPolicyFactory _parameterPolicyFactory;
 
+        private readonly (string parameterName, IRouteConstraint constraint)[] _constraints;
         private readonly RouteValueDictionary _defaults;
         private readonly KeyValuePair<string, object>[] _filters;
+        private readonly (string parameterName, IOutboundParameterTransformer transformer)[] _parameterTransformers;
         private readonly RoutePattern _pattern;
         private readonly string[] _requiredKeys;
 
@@ -44,7 +45,7 @@ namespace Microsoft.AspNetCore.Routing.Template
             ObjectPool<UriBuildingContext> pool,
             RouteTemplate template,
             RouteValueDictionary defaults)
-            : this(urlEncoder, pool, template?.ToRoutePattern(), defaults, requiredKeys: null, parameterPolicyFactory: null)
+            : this(urlEncoder, pool, template?.ToRoutePattern(), defaults, requiredKeys: null, parameterPolicies: null)
         {
         }
 
@@ -56,14 +57,16 @@ namespace Microsoft.AspNetCore.Routing.Template
         /// <param name="pattern">The <see cref="RoutePattern"/> to bind values to.</param>
         /// <param name="defaults">The default values for <paramref name="pattern"/>. Optional.</param>
         /// <param name="requiredKeys">Keys used to determine if the ambient values apply. Optional.</param>
-        /// <param name="parameterPolicyFactory">The <see cref="ParameterPolicyFactory"/>.</param>
+        /// <param name="parameterPolicies">
+        /// A list of (<see cref="string"/>, <see cref="IParameterPolicy"/>) pairs to evalute when producing a URI.
+        /// </param>
         public TemplateBinder(
             UrlEncoder urlEncoder,
             ObjectPool<UriBuildingContext> pool,
             RoutePattern pattern,
             RouteValueDictionary defaults,
             IEnumerable<string> requiredKeys,
-            ParameterPolicyFactory parameterPolicyFactory)
+            IEnumerable<(string parameterName, IParameterPolicy policy)> parameterPolicies)
         {
             if (urlEncoder == null)
             {
@@ -84,7 +87,6 @@ namespace Microsoft.AspNetCore.Routing.Template
             _pool = pool;
             _pattern = pattern;
             _defaults = defaults;
-            _parameterPolicyFactory = parameterPolicyFactory;
             _requiredKeys = requiredKeys?.ToArray() ?? Array.Empty<string>();
 
             for (var i = 0; i < _requiredKeys.Length; i++)
@@ -101,13 +103,21 @@ namespace Microsoft.AspNetCore.Routing.Template
             // Any default that doesn't have a corresponding parameter is a 'filter' and if a value
             // is provided for that 'filter' it must match the value in defaults.
             var filters = new RouteValueDictionary(_defaults);
-            foreach (var parameter in _pattern.Parameters)
+            for (var i = 0; i < pattern.Parameters.Count; i++)
             {
-                filters.Remove(parameter.Name);
+                filters.Remove(pattern.Parameters[i].Name);
             }
-
             _filters = filters.ToArray();
 
+            _constraints = parameterPolicies
+                ?.Where(p => p.policy is IRouteConstraint)
+                .Select(p => (p.parameterName, (IRouteConstraint)p.policy))
+                .ToArray() ?? Array.Empty<(string, IRouteConstraint)>();
+            _parameterTransformers = parameterPolicies
+                ?.Where(p => p.policy is IOutboundParameterTransformer)
+                .Select(p => (p.parameterName, (IOutboundParameterTransformer)p.policy))
+                .ToArray() ?? Array.Empty<(string, IOutboundParameterTransformer)>();
+
             _slots = AssignSlots(_pattern, _filters);
         }
 
@@ -351,6 +361,29 @@ namespace Microsoft.AspNetCore.Routing.Template
             };
         }
 
+        // Step 1.5: Process constraints
+        //
+        // Processes the constraints **if** they were passed in to the TemplateBinder constructor.
+        // Returns true on success
+        // Returns false + sets the name/constraint for logging on failure.
+        public bool TryProcessConstraints(HttpContext httpContext, RouteValueDictionary combinedValues, out string parameterName, out IRouteConstraint constraint)
+        {
+            var constraints = _constraints;
+            for (var i = 0; i < constraints.Length; i++)
+            {
+                (parameterName, constraint) = constraints[i];
+
+                if (!constraint.Match(httpContext, NullRouter.Instance, parameterName, combinedValues, RouteDirection.UrlGeneration))
+                {
+                    return false;
+                }
+            }
+
+            parameterName = null;
+            constraint = null;
+            return true;
+        }
+
         // Step 2: If the route is a match generate the appropriate URI
         public string BindValues(RouteValueDictionary acceptedValues)
         {
@@ -398,6 +431,18 @@ namespace Microsoft.AspNetCore.Routing.Template
 
         private bool TryBindValuesCore(UriBuildingContext context, RouteValueDictionary acceptedValues)
         {
+            // If we have any output parameter transformers, allow them a chance to influence the parameter values
+            // before we build the URI.
+            var parameterTransformers = _parameterTransformers;
+            for (var i = 0; i < parameterTransformers.Length; i++)
+            {
+                (var parameterName, var transformer) = parameterTransformers[i];
+                if (acceptedValues.TryGetValue(parameterName, out var value))
+                {
+                    acceptedValues[parameterName] = transformer.TransformOutbound(value);
+                }
+            }
+
             for (var i = 0; i < _pattern.PathSegments.Count; i++)
             {
                 Debug.Assert(context.BufferState == SegmentState.Beginning);
@@ -460,7 +505,7 @@ namespace Microsoft.AspNetCore.Routing.Template
                             // Example: template = {id}.{format?}. parameters: id=5
                             // In this case after we have generated "5.", we wont find any value 
                             // for format, so we remove '.' and generate 5.
-                            if (!context.Accept(converted, parameterPart.EncodeSlashes, GetParameterTransformer(parameterPart)))
+                            if (!context.Accept(converted, parameterPart.EncodeSlashes))
                             {
                                 if (j != 0 && parameterPart.IsOptional && (separatorPart = segment.Parts[j - 1] as RoutePatternSeparatorPart) != null)
                                 {
@@ -505,26 +550,6 @@ namespace Microsoft.AspNetCore.Routing.Template
             return true;
         }
 
-        private IParameterTransformer GetParameterTransformer(RoutePatternParameterPart parameterPart)
-        {
-            if (_parameterPolicyFactory == null)
-            {
-                return null;
-            }
-
-            for (var i = 0; i < parameterPart.ParameterPolicies.Count; i++)
-            {
-                // Use the first parameter transformer
-                var parameterPolicy = _parameterPolicyFactory.Create(parameterPart, parameterPart.ParameterPolicies[i]);
-                if (parameterPolicy is IParameterTransformer parameterTransformer)
-                {
-                    return parameterTransformer;
-                }
-            }
-
-            return null;
-        }
-
         private bool AddQueryKeyValueToContext(UriBuildingContext context, string key, object value, bool wroteFirst)
         {
             var converted = Convert.ToString(value, CultureInfo.InvariantCulture);

test/Microsoft.AspNetCore.Routing.Tests/DefaultLinkGeneratorProcessTemplateTest.cs

@@ -277,6 +277,54 @@ namespace Microsoft.AspNetCore.Routing
             Assert.Equal(string.Empty, result.query.ToUriComponent());
         }
 
+        // Regression test for https://github.com/aspnet/Routing/issues/802
+        [Fact]
+        public void TryProcessTemplate_GeneratesLowercaseUrl_Includes_BufferedValues_SetOnRouteOptions()
+        {
+            // Arrange
+            var endpoint = EndpointFactory.CreateRouteEndpoint("Foo/{bar=BAR}/{id?}");
+            var linkGenerator = CreateLinkGenerator(new RouteOptions() { LowercaseUrls = true }, endpoints: new[] { endpoint, });
+            var httpContext = CreateHttpContext();
+
+            // Act
+            var success = linkGenerator.TryProcessTemplate(
+                httpContext: httpContext,
+                endpoint: endpoint,
+                ambientValues: DefaultLinkGenerator.GetAmbientValues(httpContext),
+                explicitValues: new RouteValueDictionary(new { id = "18" }),
+                options: null,
+                out var result);
+
+            // Assert
+            Assert.True(success);
+            Assert.Equal("/foo/bar/18", result.path.ToUriComponent());
+            Assert.Equal(string.Empty, result.query.ToUriComponent());
+        }
+
+        // Regression test for https://github.com/aspnet/Routing/issues/802
+        [Fact]
+        public void TryProcessTemplate_ParameterPolicy_Includes_BufferedValues()
+        {
+            // Arrange
+            var endpoint = EndpointFactory.CreateRouteEndpoint("Foo/{bar=BAR}/{id?}", policies: new { bar = new SlugifyParameterTransformer(), });
+            var linkGenerator = CreateLinkGenerator(new RouteOptions() { LowercaseUrls = true }, endpoints: new[] { endpoint, });
+            var httpContext = CreateHttpContext();
+
+            // Act
+            var success = linkGenerator.TryProcessTemplate(
+                httpContext: httpContext,
+                endpoint: endpoint,
+                ambientValues: DefaultLinkGenerator.GetAmbientValues(httpContext),
+                explicitValues: new RouteValueDictionary(new { id = "18" }),
+                options: null,
+                out var result);
+
+            // Assert
+            Assert.True(success);
+            Assert.Equal("/foo/bar/18", result.path.ToUriComponent());
+            Assert.Equal(string.Empty, result.query.ToUriComponent());
+        }
+
         // Regression test for aspnet/Routing#435
         //
         // In this issue we used to lowercase URLs after parameters were encoded, meaning that if a character needed
@@ -531,7 +579,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 "{p1}/{p2}",
                 defaults: new { p2 = "catchall" },
-                constraints: new { p2 = "\\d{4}" });
+                policies: new { p2 = "\\d{4}" });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -555,7 +603,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 "{p1}/{p2}",
                 defaults: new { p2 = "catchall" },
-                constraints: new { p2 = new RegexRouteConstraint("\\d{4}"), });
+                policies: new { p2 = new RegexRouteConstraint("\\d{4}"), });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -581,7 +629,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 "{p1}/{*p2}",
                 defaults: new { p2 = "catchall" },
-                constraints: new { p2 = new RegexRouteConstraint("\\d{4}") });
+                policies: new { p2 = new RegexRouteConstraint("\\d{4}") });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -605,7 +653,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 "{p1}/{*p2}",
                 defaults: new { p2 = "catchall" },
-                constraints: new { p2 = new RegexRouteConstraint("\\d{4}") });
+                policies: new { p2 = new RegexRouteConstraint("\\d{4}") });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -642,7 +690,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 "{p1}/{p2}",
                 defaults: new { p2 = "catchall" },
-                constraints: new { p2 = target.Object });
+                policies: new { p2 = target.Object });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -674,7 +722,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "slug/Home/Store",
                 defaults: new { controller = "Home", action = "Store" },
-                constraints: new { c = constraint });
+                policies: new { c = constraint });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(
                 ambientValues: new { controller = "Home", action = "Blog", extra = "42" });
@@ -708,7 +756,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "slug/Home/Store",
                 defaults: new { controller = "Home", action = "Store", otherthing = "17" },
-                constraints: new { c = constraint });
+                policies: new { c = constraint });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { controller = "Home", action = "Blog" });
             var expectedValues = new RouteValueDictionary(
@@ -740,7 +788,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "slug/{controller}/{action}",
                 defaults: new { action = "Index" },
-                constraints: new { c = constraint, });
+                policies: new { c = constraint, });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { controller = "Home", action = "Blog" });
             var expectedValues = new RouteValueDictionary(
@@ -772,7 +820,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "slug/Home/Store",
                 defaults: new { controller = "Home", action = "Store", otherthing = "17", thirdthing = "13" },
-                constraints: new { c = constraint, });
+                policies: new { c = constraint, });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(
                 ambientValues: new { controller = "Home", action = "Blog", otherthing = "17" });
@@ -806,7 +854,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id:int}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { });
+                policies: new { });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = hasHttpContext ? CreateHttpContext(new { }) : null;
 
@@ -832,7 +880,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { id = "int" });
+                policies: new { id = "int" });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -858,7 +906,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id:int?}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { });
+                policies: new { });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = hasHttpContext ? CreateHttpContext(new { }) : null;
 
@@ -884,7 +932,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id?}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { id = "int" });
+                policies: new { id = "int" });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -910,7 +958,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id?}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { id = "int" });
+                policies: new { id = "int" });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 
@@ -936,7 +984,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id:int:range(1,20)}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { });
+                policies: new { });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = hasHttpContext ? CreateHttpContext(new { }) : null;
 
@@ -964,7 +1012,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{id:int:range(1,20)}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { });
+                policies: new { });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = hasHttpContext ? CreateHttpContext(new { }) : null;
 
@@ -989,7 +1037,7 @@ namespace Microsoft.AspNetCore.Routing
             var endpoint = EndpointFactory.CreateRouteEndpoint(
                 template: "Home/Index/{name}",
                 defaults: new { controller = "Home", action = "Index" },
-                constraints: new { name = constraint });
+                policies: new { name = constraint });
             var linkGenerator = CreateLinkGenerator(endpoint);
             var httpContext = CreateHttpContext(ambientValues: new { });
 

test/Microsoft.AspNetCore.Routing.Tests/DefaultLinkGeneratorTest.cs

@@ -298,11 +298,11 @@ namespace Microsoft.AspNetCore.Routing
             Assert.Equal("/Foo/Bar%3Fencodeme%3F/Home/In%3Fdex?query=some%3Fquery#Fragment?", path);
         }
 
-        private class UpperCaseParameterTransform : IParameterTransformer
+        private class UpperCaseParameterTransform : IOutboundParameterTransformer
         {
-            public string Transform(string value)
+            public string TransformOutbound(object value)
             {
-                return value?.ToUpperInvariant();
+                return value?.ToString()?.ToUpperInvariant();
             }
         }
 
@@ -329,6 +329,29 @@ namespace Microsoft.AspNetCore.Routing
             Assert.Equal("/HOME/Test", link);
         }
 
+        [Fact]
+        public void GetLink_ParameterTransformer_ForQueryString()
+        {
+            // Arrange
+            var endpoint = EndpointFactory.CreateRouteEndpoint("{controller:upper-case}/{name}", policies: new { c = new UpperCaseParameterTransform(), });
+
+            var routeOptions = new RouteOptions();
+            routeOptions.ConstraintMap["upper-case"] = typeof(UpperCaseParameterTransform);
+
+            Action<IServiceCollection> configure = (s) =>
+            {
+                s.AddSingleton(typeof(UpperCaseParameterTransform), new UpperCaseParameterTransform());
+            };
+
+            var linkGenerator = CreateLinkGenerator(routeOptions, configure, endpoint);
+
+            // Act
+            var link = linkGenerator.GetPathByRouteValues(routeName: null, new { controller = "Home", name = "Test", c = "hithere", });
+
+            // Assert
+            Assert.Equal("/HOME/Test?c=HITHERE", link);
+        }
+
         // Includes characters that need to be encoded
         [Fact]
         public void GetPathByAddress_WithHttpContext_WithPathBaseAndFragment()

test/Microsoft.AspNetCore.Routing.Tests/EndpointFactory.cs

@@ -14,7 +14,7 @@ namespace Microsoft.AspNetCore.Routing
         public static RouteEndpoint CreateRouteEndpoint(
             string template,
             object defaults = null,
-            object constraints = null,
+            object policies = null,
             object requiredValues = null,
             int order = 0,
             string displayName = null,
@@ -28,7 +28,7 @@ namespace Microsoft.AspNetCore.Routing
 
             return new RouteEndpoint(
                 TestConstants.EmptyRequestDelegate,
-                RoutePatternFactory.Parse(template, defaults, constraints),
+                RoutePatternFactory.Parse(template, defaults, policies),
                 order,
                 new EndpointMetadataCollection(d),
                 displayName);

test/Microsoft.AspNetCore.Routing.Tests/Template/TemplateBinderTests.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text.Encodings.Web;
+using Microsoft.AspNetCore.Routing.Constraints;
 using Microsoft.AspNetCore.Routing.Internal;
 using Microsoft.AspNetCore.Routing.Patterns;
 using Microsoft.AspNetCore.Routing.TestObjects;
@@ -1294,12 +1295,8 @@ namespace Microsoft.AspNetCore.Routing.Template.Tests
         public void BindValues_ParameterTransformer()
         {
             // Arrange
-            var routeOptions = new RouteOptions();
-            routeOptions.ConstraintMap["slugify"] = typeof(SlugifyParameterTransformer);
-            var parameterPolicyFactory = new DefaultParameterPolicyFactory(
-                Options.Create(routeOptions),
-                new ServiceCollection().BuildServiceProvider());
             var expected = "/ConventionalTransformerRoute/conventional-transformer/Param/my-value";
+
             var template = "ConventionalTransformerRoute/conventional-transformer/Param/{param:length(500):slugify?}";
             var defaults = new RouteValueDictionary(new { controller = "ConventionalTransformer", action = "Param" });
             var ambientValues = new RouteValueDictionary(new { controller = "ConventionalTransformer", action = "Param" });
@@ -1310,7 +1307,7 @@ namespace Microsoft.AspNetCore.Routing.Template.Tests
                 RoutePatternFactory.Parse(template),
                 defaults,
                 requiredKeys: defaults.Keys,
-                parameterPolicyFactory);
+                parameterPolicies: new (string, IParameterPolicy)[] { ("param", new LengthRouteConstraint(500)), ("param", new SlugifyParameterTransformer()), });
 
             // Act
             var result = binder.GetValues(ambientValues, explicitValues);

test/Microsoft.AspNetCore.Routing.Tests/TestObjects/SlugifyParameterTransformer.cs

@@ -1,17 +1,16 @@
 // 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.Text.RegularExpressions;
 
 namespace Microsoft.AspNetCore.Routing.TestObjects
 {
-    public class SlugifyParameterTransformer : IParameterTransformer
+    public class SlugifyParameterTransformer : IOutboundParameterTransformer
     {
-        public string Transform(string value)
+        public string TransformOutbound(object value)
         {
             // Slugify value
-            return Regex.Replace(value, "([a-z])([A-Z])", "$1-$2").ToLower();
+            return value == null ? null : Regex.Replace(value.ToString(), "([a-z])([A-Z])", "$1-$2").ToLower();
         }
     }
 }