[Blazor] Consume fingerprinted assets in MVC and Blazor

AspNetCore.sln

@@ -1816,6 +1816,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "GetDocumentInsider.Tests",
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "GetDocumentSample", "src\Tools\GetDocumentInsider\sample\GetDocumentSample.csproj", "{D8F7091E-A2D1-4E81-BA7C-97EAE392D683}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "BlazorUnitedApp.Client", "src\Components\Samples\BlazorUnitedApp.Client\BlazorUnitedApp.Client.csproj", "{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -10977,6 +10979,22 @@ Global
 		{D8F7091E-A2D1-4E81-BA7C-97EAE392D683}.Release|x64.Build.0 = Release|Any CPU
 		{D8F7091E-A2D1-4E81-BA7C-97EAE392D683}.Release|x86.ActiveCfg = Release|Any CPU
 		{D8F7091E-A2D1-4E81-BA7C-97EAE392D683}.Release|x86.Build.0 = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|arm64.ActiveCfg = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|arm64.Build.0 = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|x64.Build.0 = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Debug|x86.Build.0 = Debug|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|Any CPU.Build.0 = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|arm64.ActiveCfg = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|arm64.Build.0 = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|x64.ActiveCfg = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|x64.Build.0 = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|x86.ActiveCfg = Release|Any CPU
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -11874,6 +11892,7 @@ Global
 		{9536C284-65B4-4884-BB50-06D629095C3E} = {274100A5-5B2D-4EA2-AC42-A62257FC6BDC}
 		{6A19D94D-2BC6-4198-BE2E-342688FDBA4B} = {A1B75FC7-A777-4412-A635-D0C9ED8FE7A0}
 		{D8F7091E-A2D1-4E81-BA7C-97EAE392D683} = {A1B75FC7-A777-4412-A635-D0C9ED8FE7A0}
+		{757CBDE0-5D0A-4FD8-99F3-6C20BDDD4E63} = {5FE1FBC1-8CE3-4355-9866-44FE1307C5F1}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {3E8720B3-DBDD-498C-B383-2CC32A054E8F}

src/Components/Components.slnf

@@ -19,6 +19,7 @@
       "src\\Components\\QuickGrid\\Microsoft.AspNetCore.Components.QuickGrid.EntityFrameworkAdapter\\src\\Microsoft.AspNetCore.Components.QuickGrid.EntityFrameworkAdapter.csproj",
       "src\\Components\\QuickGrid\\Microsoft.AspNetCore.Components.QuickGrid\\src\\Microsoft.AspNetCore.Components.QuickGrid.csproj",
       "src\\Components\\Samples\\BlazorServerApp\\BlazorServerApp.csproj",
+      "src\\Components\\Samples\\BlazorUnitedApp.Client\\BlazorUnitedApp.Client.csproj",
       "src\\Components\\Samples\\BlazorUnitedApp\\BlazorUnitedApp.csproj",
       "src\\Components\\Server\\src\\Microsoft.AspNetCore.Components.Server.csproj",
       "src\\Components\\Server\\test\\Microsoft.AspNetCore.Components.Server.Tests.csproj",

src/Components/Components/src/ComponentBase.cs

@@ -47,6 +47,11 @@ public ComponentBase()
     /// </summary>
     protected ComponentPlatform Platform => _renderHandle.Platform;
 
+    /// <summary>
+    /// Gets the <see cref="ResourceAssetCollection"/> for the application.
+    /// </summary>
+    protected ResourceAssetCollection Assets => _renderHandle.Assets;
+
     /// <summary>
     /// Gets the <see cref="IComponentRenderMode"/> assigned to this component.
     /// </summary>

src/Components/Components/src/PublicAPI.Unshipped.txt

@@ -1,4 +1,5 @@
 #nullable enable
+Microsoft.AspNetCore.Components.ComponentBase.Assets.get -> Microsoft.AspNetCore.Components.ResourceAssetCollection!
 Microsoft.AspNetCore.Components.ComponentBase.AssignedRenderMode.get -> Microsoft.AspNetCore.Components.IComponentRenderMode?
 Microsoft.AspNetCore.Components.ComponentBase.Platform.get -> Microsoft.AspNetCore.Components.ComponentPlatform!
 Microsoft.AspNetCore.Components.ComponentPlatform
@@ -7,6 +8,21 @@ Microsoft.AspNetCore.Components.ComponentPlatform.IsInteractive.get -> bool
 Microsoft.AspNetCore.Components.ComponentPlatform.Name.get -> string!
 Microsoft.AspNetCore.Components.ExcludeFromInteractiveRoutingAttribute
 Microsoft.AspNetCore.Components.ExcludeFromInteractiveRoutingAttribute.ExcludeFromInteractiveRoutingAttribute() -> void
+Microsoft.AspNetCore.Components.RenderHandle.Assets.get -> Microsoft.AspNetCore.Components.ResourceAssetCollection!
 Microsoft.AspNetCore.Components.RenderHandle.Platform.get -> Microsoft.AspNetCore.Components.ComponentPlatform!
 Microsoft.AspNetCore.Components.RenderHandle.RenderMode.get -> Microsoft.AspNetCore.Components.IComponentRenderMode?
+Microsoft.AspNetCore.Components.ResourceAsset
+Microsoft.AspNetCore.Components.ResourceAsset.Properties.get -> System.Collections.Generic.IReadOnlyList<Microsoft.AspNetCore.Components.ResourceAssetProperty!>?
+Microsoft.AspNetCore.Components.ResourceAsset.ResourceAsset(string! url, System.Collections.Generic.IReadOnlyList<Microsoft.AspNetCore.Components.ResourceAssetProperty!>? properties) -> void
+Microsoft.AspNetCore.Components.ResourceAsset.Url.get -> string!
+Microsoft.AspNetCore.Components.ResourceAssetCollection
+Microsoft.AspNetCore.Components.ResourceAssetCollection.IsContentSpecificUrl(string! path) -> bool
+Microsoft.AspNetCore.Components.ResourceAssetCollection.ResourceAssetCollection(System.Collections.Generic.IReadOnlyList<Microsoft.AspNetCore.Components.ResourceAsset!>! resources) -> void
+Microsoft.AspNetCore.Components.ResourceAssetCollection.this[string! key].get -> string!
+Microsoft.AspNetCore.Components.ResourceAssetProperty
+Microsoft.AspNetCore.Components.ResourceAssetProperty.Name.get -> string!
+Microsoft.AspNetCore.Components.ResourceAssetProperty.ResourceAssetProperty(string! name, string! value) -> void
+Microsoft.AspNetCore.Components.ResourceAssetProperty.Value.get -> string!
+static readonly Microsoft.AspNetCore.Components.ResourceAssetCollection.Empty -> Microsoft.AspNetCore.Components.ResourceAssetCollection!
+virtual Microsoft.AspNetCore.Components.RenderTree.Renderer.Assets.get -> Microsoft.AspNetCore.Components.ResourceAssetCollection!
 virtual Microsoft.AspNetCore.Components.RenderTree.Renderer.ComponentPlatform.get -> Microsoft.AspNetCore.Components.ComponentPlatform!

src/Components/Components/src/RenderHandle.cs

@@ -73,6 +73,17 @@ public IComponentRenderMode? RenderMode
         }
     }
 
+    /// <summary>
+    /// Gets the <see cref="ResourceAssetCollection"/> associated with the <see cref="Renderer"/>.
+    /// </summary>
+    public ResourceAssetCollection Assets
+    {
+        get
+        {
+            return _renderer?.Assets ?? throw new InvalidOperationException("No renderer has been initialized.");
+        }
+    }
+
     /// <summary>
     /// Notifies the renderer that the component should be rendered.
     /// </summary>

src/Components/Components/src/RenderTree/Renderer.cs

@@ -158,6 +158,11 @@ protected internal ComponentState GetComponentState(IComponent component)
     /// </summary>
     protected internal virtual ComponentPlatform ComponentPlatform { get; }
 
+    /// <summary>
+    /// Gets the <see cref="ResourceAssetCollection"/> associated with this <see cref="Renderer"/>.
+    /// </summary>
+    protected internal virtual ResourceAssetCollection Assets { get; } = ResourceAssetCollection.Empty;
+
     private async void RenderRootComponentsOnHotReload()
     {
         // Before re-rendering the root component, also clear any well-known caches in the framework

src/Components/Components/src/ResourceAsset.cs

@@ -0,0 +1,29 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Diagnostics;
+using System.Linq;
+
+namespace Microsoft.AspNetCore.Components;
+
+/// <summary>
+/// A resource of the components application, such as a script, stylesheet or image.
+/// </summary>
+/// <param name="url">The URL of the resource.</param>
+/// <param name="properties">The properties associated to this resource.</param>
+[DebuggerDisplay($"{{{nameof(GetDebuggerDisplay)}(),nq}}")]
+public sealed class ResourceAsset(string url, IReadOnlyList<ResourceAssetProperty>? properties)
+{
+    /// <summary>
+    /// Gets the URL that identifies this resource.
+    /// </summary>
+    public string Url { get; } = url;
+
+    /// <summary>
+    /// Gets a list of properties associated to this resource.
+    /// </summary>
+    public IReadOnlyList<ResourceAssetProperty>? Properties { get; } = properties;
+
+    private string GetDebuggerDisplay() =>
+        $"Url: '{Url}' - Properties: {string.Join(", ", Properties?.Select(p => $"{p.Name} = {p.Value}") ?? [])}";
+}

src/Components/Components/src/ResourceAssetCollection.cs

@@ -0,0 +1,71 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Collections;
+using System.Collections.Frozen;
+
+namespace Microsoft.AspNetCore.Components;
+
+/// <summary>
+/// Describes a mapping of static assets to their corresponding unique URLs.
+/// </summary>
+public sealed class ResourceAssetCollection : IReadOnlyList<ResourceAsset>
+{
+    /// <summary>
+    /// An empty <see cref="ResourceAssetCollection"/>.
+    /// </summary>
+    public static readonly ResourceAssetCollection Empty = new([]);
+
+    private readonly FrozenDictionary<string, ResourceAsset> _uniqueUrlMappings;
+    private readonly FrozenSet<string> _contentSpecificUrls;
+    private readonly IReadOnlyList<ResourceAsset> _resources;
+
+    /// <summary>
+    /// Initializes a new instance of <see cref="ResourceAssetCollection"/>
+    /// </summary>
+    /// <param name="resources">The list of resources available.</param>
+    public ResourceAssetCollection(IReadOnlyList<ResourceAsset> resources)
+    {
+        var mappings = new Dictionary<string, ResourceAsset>(StringComparer.OrdinalIgnoreCase);
+        var contentSpecificUrls = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+        _resources = resources;
+        foreach (var resource in resources)
+        {
+            foreach (var property in resource.Properties ?? [])
+            {
+                if (property.Name.Equals("label", StringComparison.OrdinalIgnoreCase))
+                {
+                    if (mappings.TryGetValue(property.Value, out var value))
+                    {
+                        throw new InvalidOperationException($"The static asset '{property.Value}' is already mapped to {value.Url}.");
+                    }
+                    mappings[property.Value] = resource;
+                    contentSpecificUrls.Add(resource.Url);
+                }
+            }
+        }
+
+        _uniqueUrlMappings = mappings.ToFrozenDictionary();
+        _contentSpecificUrls = contentSpecificUrls.ToFrozenSet();
+    }
+
+    /// <summary>
+    /// Gets the unique content-based URL for the specified static asset.
+    /// </summary>
+    /// <param name="key">The asset name.</param>
+    /// <returns>The unique URL if availabe, the same <paramref name="key"/> if not available.</returns>
+    public string this[string key] => _uniqueUrlMappings.TryGetValue(key, out var value) ? value.Url : key;
+
+    /// <summary>
+    /// Determines whether the specified path is a content-specific URL.
+    /// </summary>
+    /// <param name="path">The path to check.</param>
+    /// <returns><c>true</c> if the path is a content-specific URL; otherwise, <c>false</c>.</returns>
+    public bool IsContentSpecificUrl(string path) => _contentSpecificUrls.Contains(path);
+
+    // IReadOnlyList<ResourceAsset> implementation
+    ResourceAsset IReadOnlyList<ResourceAsset>.this[int index] => _resources[index];
+    int IReadOnlyCollection<ResourceAsset>.Count => _resources.Count;
+    IEnumerator<ResourceAsset> IEnumerable<ResourceAsset>.GetEnumerator() => _resources.GetEnumerator();
+    IEnumerator IEnumerable.GetEnumerator() => _resources.GetEnumerator();
+}

src/Components/Components/src/ResourceAssetProperty.cs

@@ -0,0 +1,22 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.AspNetCore.Components;
+
+/// <summary>
+/// A resource property.
+/// </summary>
+/// <param name="name">The name of the property.</param>
+/// <param name="value">The value of the property.</param>
+public sealed class ResourceAssetProperty(string name, string value)
+{
+    /// <summary>
+    /// Gets the name of the property.
+    /// </summary>
+    public string Name { get; } = name;
+
+    /// <summary>
+    /// Gets the value of the property.
+    /// </summary>
+    public string Value { get; } = value;
+}

src/Components/Components/test/ResourceAssetCollectionTest.cs

@@ -0,0 +1,88 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.AspNetCore.Components;
+
+public class ResourceAssetCollectionTest
+{
+    [Fact]
+    public void CanCreateResourceCollection()
+    {
+        // Arrange
+        var resourceAssetCollection = new ResourceAssetCollection([
+            new ResourceAsset("image1.jpg",[]),
+            ]);
+
+        // Act
+        var collectionAsReadOnlyList = resourceAssetCollection as IReadOnlyList<ResourceAsset>;
+
+        // Assert
+        Assert.Equal(1, collectionAsReadOnlyList.Count);
+        Assert.Equal("image1.jpg", collectionAsReadOnlyList[0].Url);
+    }
+
+    [Fact]
+    public void CanResolveFingerprintedResources()
+    {
+        // Arrange
+        var resourceAssetCollection = new ResourceAssetCollection([
+            new ResourceAsset(
+                "image1.fingerprint.jpg",
+                [new ResourceAssetProperty("label", "image1.jpg")]),
+            ]);
+
+        // Act
+        var resolvedUrl = resourceAssetCollection["image1.jpg"];
+
+        // Assert
+        Assert.Equal("image1.fingerprint.jpg", resolvedUrl);
+    }
+
+    [Fact]
+    public void ResolvingNoFingerprintedResourcesReturnsSameUrl()
+    {
+        // Arrange
+        var resourceAssetCollection = new ResourceAssetCollection([
+            new ResourceAsset("image1.jpg",[])]);
+
+        // Act
+        var resolvedUrl = resourceAssetCollection["image1.jpg"];
+
+        // Assert
+        Assert.Equal("image1.jpg", resolvedUrl);
+    }
+
+    [Fact]
+    public void ResolvingNonExistentResourceReturnsSameUrl()
+    {
+        // Arrange
+        var resourceAssetCollection = new ResourceAssetCollection([
+            new ResourceAsset("image1.jpg",[])]);
+
+        // Act
+        var resolvedUrl = resourceAssetCollection["image2.jpg"];
+
+        // Assert
+        Assert.Equal("image2.jpg", resolvedUrl);
+    }
+
+    [Fact]
+    public void CanDetermineContentSpecificUrls()
+    {
+        // Arrange
+        var resourceAssetCollection = new ResourceAssetCollection([
+            new ResourceAsset("image1.jpg",[]),
+            new ResourceAsset(
+                "image2.fingerprint.jpg",
+                [new ResourceAssetProperty("label", "image2.jpg")]),
+            ]);
+
+        // Act
+        var isContentSpecificUrl1 = resourceAssetCollection.IsContentSpecificUrl("image1.jpg");
+        var isContentSpecificUrl2 = resourceAssetCollection.IsContentSpecificUrl("image2.fingerprint.jpg");
+
+        // Assert
+        Assert.False(isContentSpecificUrl1);
+        Assert.True(isContentSpecificUrl2);
+    }
+}

src/Components/Endpoints/src/Assets/ImportMap.cs

@@ -0,0 +1,63 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Microsoft.AspNetCore.Components.Rendering;
+using Microsoft.AspNetCore.Http;
+
+namespace Microsoft.AspNetCore.Components;
+
+/// <summary>
+/// Represents an <c><script type="importmap"></script></c> element that defines the import map for module scripts
+/// in the application.
+/// </summary>
+public sealed class ImportMap : IComponent
+{
+    private RenderHandle _renderHandle;
+    private bool _firstRender = true;
+    private ImportMapDefinition? _computedImportMapDefinition;
+
+    /// <summary>
+    /// Gets or sets the <see cref="HttpContext"/> for the component.
+    /// </summary>
+    [CascadingParameter] public HttpContext? HttpContext { get; set; } = null;
+
+    /// <summary>
+    /// Gets or sets the import map definition to use for the component. If not set
+    /// the component will generate the import map based on the assets defined for this
+    /// application.
+    /// </summary>
+    [Parameter]
+    public ImportMapDefinition? ImportMapDefinition { get; set; }
+
+    void IComponent.Attach(RenderHandle renderHandle)
+    {
+        _renderHandle = renderHandle;
+    }
+
+    Task IComponent.SetParametersAsync(ParameterView parameters)
+    {
+        parameters.SetParameterProperties(this);
+        if (!_firstRender && ReferenceEquals(ImportMapDefinition, _computedImportMapDefinition))
+        {
+            return Task.CompletedTask;
+        }
+        else
+        {
+            _firstRender = false;
+            _computedImportMapDefinition = ImportMapDefinition ?? HttpContext?.GetEndpoint()?.Metadata.GetMetadata<ImportMapDefinition>();
+            if (_computedImportMapDefinition != null)
+            {
+                _renderHandle.Render(RenderImportMap);
+            }
+            return Task.CompletedTask;
+        }
+    }
+
+    private void RenderImportMap(RenderTreeBuilder builder)
+    {
+        builder.OpenElement(0, "script");
+        builder.AddAttribute(1, "type", "importmap");
+        builder.AddMarkupContent(2, _computedImportMapDefinition!.ToJson());
+        builder.CloseElement();
+    }
+}