Adding PageActionDescriptorProvider

Fixes #5353

src/Microsoft.AspNetCore.Mvc.Core/ApplicationModels/AttributeRouteModel.cs

@@ -99,6 +99,33 @@ public static AttributeRouteModel CombineAttributeRouteModel(
             };
         }
 
+        /// <summary>
+        /// Combines the prefix and route template for an attribute route.
+        /// </summary>
+        /// <param name="prefix">The prefix.</param>
+        /// <param name="template">The route template.</param>
+        /// <returns>The combined pattern.</returns>
+        public static string CombineTemplates(string prefix, string template)
+        {
+            var result = CombineCore(prefix, template);
+            return CleanTemplate(result);
+        }
+
+        /// <summary>
+        /// Determines if a template pattern can be used to override a prefix.
+        /// </summary>
+        /// <param name="template">The template.</param>
+        /// <returns><c>true</c> if this is an overriding template, <c>false</c> otherwise.</returns>
+        /// <remarks>
+        /// Route templates starting with "~/" or "/" can be used to override the prefix.
+        /// </remarks>
+        public static bool IsOverridePattern(string template)
+        {
+            return template != null &&
+                (template.StartsWith("~/", StringComparison.Ordinal) ||
+                template.StartsWith("/", StringComparison.Ordinal));
+        }
+
         private static string ChooseName(
             AttributeRouteModel left,
             AttributeRouteModel right)
@@ -113,12 +140,6 @@ private static string ChooseName(
             }
         }
 
-        internal static string CombineTemplates(string left, string right)
-        {
-            var result = CombineCore(left, right);
-            return CleanTemplate(result);
-        }
-
         private static string CombineCore(string left, string right)
         {
             if (left == null && right == null)
@@ -143,13 +164,6 @@ private static string CombineCore(string left, string right)
             return left + "/" + right;
         }
 
-        private static bool IsOverridePattern(string template)
-        {
-            return template != null &&
-                (template.StartsWith("~/", StringComparison.Ordinal) ||
-                template.StartsWith("/", StringComparison.Ordinal));
-        }
-
         private static bool IsEmptyLeftSegment(string template)
         {
             return template == null ||

src/Microsoft.AspNetCore.Mvc.Core/Internal/ControllerActionDescriptorBuilder.cs

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.Globalization;
 using System.Linq;
 using System.Reflection;
 using Microsoft.AspNetCore.Mvc.Abstractions;
@@ -14,7 +13,6 @@
 using Microsoft.AspNetCore.Mvc.Core;
 using Microsoft.AspNetCore.Mvc.Filters;
 using Microsoft.AspNetCore.Mvc.Routing;
-using Microsoft.AspNetCore.Routing.Tree;
 
 namespace Microsoft.AspNetCore.Mvc.Internal
 {

src/Microsoft.AspNetCore.Mvc.RazorPages/ApplicationModels/IPageModelConvention.cs

@@ -0,0 +1,17 @@
+// 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.
+
+namespace Microsoft.AspNetCore.Mvc.ApplicationModels
+{
+    /// <summary>
+    /// Allows customization of the of the <see cref="PageModel"/>.
+    /// </summary>
+    public interface IPageModelConvention
+    {
+        /// <summary>
+        /// Called to apply the convention to the <see cref="PageModel"/>.
+        /// </summary>
+        /// <param name="model">The <see cref="PageModel"/>.</param>
+        void Apply(PageModel model);
+    }
+}

src/Microsoft.AspNetCore.Mvc.RazorPages/ApplicationModels/PageModels.cs

@@ -0,0 +1,86 @@
+// 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.Collections.Generic;
+using System.Linq;
+using Microsoft.AspNetCore.Mvc.Filters;
+
+namespace Microsoft.AspNetCore.Mvc.ApplicationModels
+{
+    /// <summary>
+    /// Application model component for RazorPages.
+    /// </summary>
+    public class PageModel
+    {
+        /// <summary>
+        /// Initializes a new instance of <see cref="PageModel"/>.
+        /// </summary>
+        /// <param name="relativePath">The application relative path of the page.</param>
+        /// <param name="viewEnginePath">The path relative to the base path for page discovery.</param>
+        public PageModel(string relativePath, string viewEnginePath)
+        {
+            if (relativePath == null)
+            {
+                throw new ArgumentNullException(nameof(relativePath));
+            }
+
+            if (viewEnginePath == null)
+            {
+                throw new ArgumentNullException(nameof(viewEnginePath));
+            }
+
+            RelativePath = relativePath;
+            ViewEnginePath = viewEnginePath;
+
+            Filters = new List<IFilterMetadata>();
+            Properties = new Dictionary<object, object>();
+            Selectors = new List<SelectorModel>();
+        }
+
+        /// <summary>
+        /// A copy constructor for <see cref="PageModel"/>.
+        /// </summary>
+        /// <param name="other">The <see cref="PageModel"/> to copy from.</param>
+        public PageModel(PageModel other)
+        {
+            if (other == null)
+            {
+                throw new ArgumentNullException(nameof(other));
+            }
+
+            RelativePath = other.RelativePath;
+            ViewEnginePath = other.ViewEnginePath;
+
+            Filters = new List<IFilterMetadata>(other.Filters);
+            Properties = new Dictionary<object, object>(other.Properties);
+
+            Selectors = new List<SelectorModel>(other.Selectors.Select(m => new SelectorModel(m)));
+        }
+
+        /// <summary>
+        /// Gets or sets the application root relative path for the page.
+        /// </summary>
+        public string RelativePath { get; }
+
+        /// <summary>
+        /// Gets or sets the path relative to the base path for page discovery.
+        /// </summary>
+        public string ViewEnginePath { get; }
+
+        /// <summary>
+        /// Gets or sets the applicable <see cref="IFilterMetadata"/> instances.
+        /// </summary>
+        public IList<IFilterMetadata> Filters { get; }
+
+        /// <summary>
+        /// Stores arbitrary metadata properties associated with the <see cref="PageModel"/>.
+        /// </summary>
+        public IDictionary<object, object> Properties { get; }
+
+        /// <summary>
+        /// Gets or sets the <see cref="SelectorModel"/> instances.
+        /// </summary>
+        public IList<SelectorModel> Selectors { get; }
+    }
+}

src/Microsoft.AspNetCore.Mvc.RazorPages/Infrastructure/PageActionDescriptorProvider.cs

@@ -0,0 +1,127 @@
+// 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.Collections.Generic;
+using Microsoft.AspNetCore.Mvc.Abstractions;
+using Microsoft.AspNetCore.Mvc.ApplicationModels;
+using Microsoft.AspNetCore.Mvc.Filters;
+using Microsoft.AspNetCore.Mvc.Routing;
+using Microsoft.AspNetCore.Razor.Evolution;
+using Microsoft.Extensions.Options;
+
+namespace Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure
+{
+    public class PageActionDescriptorProvider : IActionDescriptorProvider
+    {
+        private static readonly string IndexFileName = "Index.cshtml";
+        private readonly RazorProject _project;
+        private readonly MvcOptions _mvcOptions;
+        private readonly RazorPagesOptions _pagesOptions;
+
+        public PageActionDescriptorProvider(
+            RazorProject project,
+            IOptions<MvcOptions> mvcOptionsAccessor,
+            IOptions<RazorPagesOptions> pagesOptionsAccessor)
+        {
+            _project = project;
+            _mvcOptions = mvcOptionsAccessor.Value;
+            _pagesOptions = pagesOptionsAccessor.Value;
+        }
+
+        public int Order { get; set; }
+
+        public void OnProvidersExecuting(ActionDescriptorProviderContext context)
+        {
+            foreach (var item in _project.EnumerateItems("/"))
+            {
+                if (item.Filename.StartsWith("_"))
+                {
+                    // Pages like _PageImports should not be routable.
+                    continue;
+                }
+
+                string template;
+                if (!PageDirectiveFeature.TryGetRouteTemplate(item, out template))
+                {
+                    // .cshtml pages without @page are not RazorPages.
+                    continue;
+                }
+
+                if (AttributeRouteModel.IsOverridePattern(template))
+                {
+                    throw new InvalidOperationException(string.Format(
+                        Resources.PageActionDescriptorProvider_RouteTemplateCannotBeOverrideable,
+                        item.Path));
+                }
+
+                AddActionDescriptors(context.Results, item, template);
+            }
+        }
+
+        public void OnProvidersExecuted(ActionDescriptorProviderContext context)
+        {
+        }
+
+        private void AddActionDescriptors(IList<ActionDescriptor> actions, RazorProjectItem item, string template)
+        {
+            var model = new PageModel(item.CombinedPath, item.PathWithoutExtension);
+            var routePrefix = item.BasePath == "/" ? item.PathWithoutExtension : item.BasePath + item.PathWithoutExtension;
+            model.Selectors.Add(CreateSelectorModel(routePrefix, template));
+
+            if (string.Equals(IndexFileName, item.Filename, StringComparison.OrdinalIgnoreCase))
+            {
+                model.Selectors.Add(CreateSelectorModel(item.BasePath, template));
+            }
+
+            for (var i = 0; i < _pagesOptions.Conventions.Count; i++)
+            {
+                _pagesOptions.Conventions[i].Apply(model);
+            }
+
+            var filters = new List<FilterDescriptor>(_mvcOptions.Filters.Count + model.Filters.Count);
+            for (var i = 0; i < _mvcOptions.Filters.Count; i++)
+            {
+                filters.Add(new FilterDescriptor(_mvcOptions.Filters[i], FilterScope.Global));
+            }
+
+            for (var i = 0; i < model.Filters.Count; i++)
+            {
+                filters.Add(new FilterDescriptor(model.Filters[i], FilterScope.Action));
+            }
+
+            foreach (var selector in model.Selectors)
+            {
+                actions.Add(new PageActionDescriptor()
+                {
+                    AttributeRouteInfo = new AttributeRouteInfo()
+                    {
+                        Name = selector.AttributeRouteModel.Name,
+                        Order = selector.AttributeRouteModel.Order ?? 0,
+                        Template = selector.AttributeRouteModel.Template,
+                    },
+                    DisplayName = $"Page: {item.Path}",
+                    FilterDescriptors = filters,
+                    Properties = new Dictionary<object, object>(model.Properties),
+                    RelativePath = item.CombinedPath,
+                    RouteValues = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+                    {
+                        { "page", item.PathWithoutExtension },
+                    },
+                    ViewEnginePath = item.Path,
+                });
+            }
+        }
+
+        private static SelectorModel CreateSelectorModel(string prefix, string template)
+        {
+            return new SelectorModel
+            {
+                AttributeRouteModel = new AttributeRouteModel
+                {
+                    Template = AttributeRouteModel.CombineTemplates(prefix, template),
+                }
+            };
+        }
+    }
+}

src/Microsoft.AspNetCore.Mvc.RazorPages/Infrastructure/PageDirectiveFeature.cs

@@ -0,0 +1,33 @@
+// 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.IO;
+using Microsoft.AspNetCore.Razor.Evolution;
+
+namespace Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure
+{
+    public static class PageDirectiveFeature
+    {
+        public static bool TryGetRouteTemplate(RazorProjectItem projectItem, out string template)
+        {
+            const string PageDirective = "@page";
+
+            string content;
+            using (var streamReader = new StreamReader(projectItem.Read()))
+            {
+                content = streamReader.ReadToEnd();
+            }
+
+            if (content.StartsWith(PageDirective, StringComparison.Ordinal))
+            {
+                var newLineIndex = content.IndexOf(Environment.NewLine, PageDirective.Length);
+                template = content.Substring(PageDirective.Length, newLineIndex - PageDirective.Length).Trim();
+                return true;
+            }
+
+            template = null;
+            return false;
+        }
+    }
+}