Fix hot reload for Blazor route changes (#63972)

oroztocil · Copilot · web-flow · commit 982cae2c12ae · 2025-10-09T20:25:23.000+02:00
* Fix hot reload for Blazor route changes

* Update src/Components/Endpoints/test/HotReloadServiceTests.cs

Co-authored-by: Copilot &lt;175728472+Copilot@users.noreply.github.com&gt;

---------

Co-authored-by: Copilot &lt;175728472+Copilot@users.noreply.github.com&gt;
diff --git a/src/Components/Endpoints/src/Builder/RazorComponentEndpointDataSource.cs b/src/Components/Endpoints/src/Builder/RazorComponentEndpointDataSource.cs
@@ -20,8 +20,8 @@ internal class RazorComponentEndpointDataSource<[DynamicallyAccessedMembers(Comp
     private readonly object _lock = new();
     private readonly List<Action<EndpointBuilder>> _conventions = [];
     private readonly List<Action<EndpointBuilder>> _finallyConventions = [];
+    private readonly List<Action<ComponentApplicationBuilder>> _componentApplicationBuilderActions = [];
     private readonly RazorComponentDataSourceOptions _options = new();
-    private readonly ComponentApplicationBuilder _builder;
     private readonly IEndpointRouteBuilder _endpointRouteBuilder;
     private readonly ResourceCollectionResolver _resourceCollectionResolver;
     private readonly RenderModeEndpointProvider[] _renderModeEndpointProviders;
@@ -32,33 +32,29 @@ internal class RazorComponentEndpointDataSource<[DynamicallyAccessedMembers(Comp
     private IChangeToken _changeToken;
     private IDisposable? _disposableChangeToken;   // THREADING: protected by _lock
 
-    public Func<IDisposable, IDisposable> SetDisposableChangeTokenAction = disposableChangeToken => disposableChangeToken;
-
     // Internal for testing.
-    internal ComponentApplicationBuilder Builder => _builder;
     internal List<Action<EndpointBuilder>> Conventions => _conventions;
+    internal List<Action<ComponentApplicationBuilder>> ComponentApplicationBuilderActions => _componentApplicationBuilderActions;
+    internal CancellationTokenSource ChangeTokenSource => _cancellationTokenSource;
 
     public RazorComponentEndpointDataSource(
-        ComponentApplicationBuilder builder,
         IEnumerable<RenderModeEndpointProvider> renderModeEndpointProviders,
         IEndpointRouteBuilder endpointRouteBuilder,
         RazorComponentEndpointFactory factory,
         HotReloadService? hotReloadService = null)
     {
-        _builder = builder;
         _endpointRouteBuilder = endpointRouteBuilder;
         _resourceCollectionResolver = new ResourceCollectionResolver(endpointRouteBuilder);
         _renderModeEndpointProviders = renderModeEndpointProviders.ToArray();
         _factory = factory;
         _hotReloadService = hotReloadService;
-        HotReloadService.ClearCacheEvent += OnHotReloadClearCache;
         DefaultBuilder = new RazorComponentsEndpointConventionBuilder(
             _lock,
-            builder,
             endpointRouteBuilder,
             _options,
             _conventions,
-            _finallyConventions);
+            _finallyConventions,
+            _componentApplicationBuilderActions);
 
         _cancellationTokenSource = new CancellationTokenSource();
         _changeToken = new CancellationChangeToken(_cancellationTokenSource.Token);
@@ -106,8 +102,20 @@ private void UpdateEndpoints()
 
         lock (_lock)
         {
+            _disposableChangeToken?.Dispose();
+            _disposableChangeToken = null;
+
             var endpoints = new List<Endpoint>();
-            var context = _builder.Build();
+
+            var componentApplicationBuilder = new ComponentApplicationBuilder();
+
+            foreach (var action in ComponentApplicationBuilderActions)
+            {
+                action?.Invoke(componentApplicationBuilder);
+            }
+
+            var context = componentApplicationBuilder.Build();
+
             var configuredRenderModesMetadata = new ConfiguredRenderModesMetadata(
                 [.. Options.ConfiguredRenderModes]);
 
@@ -168,8 +176,7 @@ private void UpdateEndpoints()
             oldCancellationTokenSource?.Dispose();
             if (_hotReloadService is { MetadataUpdateSupported: true })
             {
-                _disposableChangeToken?.Dispose();
-                _disposableChangeToken = SetDisposableChangeTokenAction(ChangeToken.OnChange(_hotReloadService.GetChangeToken, UpdateEndpoints));
+                _disposableChangeToken = ChangeToken.OnChange(_hotReloadService.GetChangeToken, UpdateEndpoints);
             }
         }
     }
@@ -195,15 +202,6 @@ private void AddBlazorWebEndpoints(List<Endpoint> endpoints)
         }
     }
 
-    public void OnHotReloadClearCache(Type[]? types)
-    {
-        lock (_lock)
-        {
-            _disposableChangeToken?.Dispose();
-            _disposableChangeToken = null;
-        }
-    }
-
     public override IChangeToken GetChangeToken()
     {
         Initialize();
diff --git a/src/Components/Endpoints/src/Builder/RazorComponentEndpointDataSourceFactory.cs b/src/Components/Endpoints/src/Builder/RazorComponentEndpointDataSourceFactory.cs
@@ -17,9 +17,14 @@ internal class RazorComponentEndpointDataSourceFactory(
 {
     public RazorComponentEndpointDataSource<TRootComponent> CreateDataSource<[DynamicallyAccessedMembers(Component)] TRootComponent>(IEndpointRouteBuilder endpoints)
     {
-        var builder = ComponentApplicationBuilder.GetBuilder<TRootComponent>() ??
-            DefaultRazorComponentApplication<TRootComponent>.Instance.GetBuilder();
+        var dataSource = new RazorComponentEndpointDataSource<TRootComponent>(providers, endpoints, factory, hotReloadService);
 
-        return new RazorComponentEndpointDataSource<TRootComponent>(builder, providers, endpoints, factory, hotReloadService);
+        dataSource.ComponentApplicationBuilderActions.Add(builder =>
+        {
+            var assembly = typeof(TRootComponent).Assembly;
+            IRazorComponentApplication.GetBuilderForAssembly(builder, assembly);
+        });
+
+        return dataSource;
     }
 }
diff --git a/src/Components/Endpoints/src/Builder/RazorComponentsEndpointConventionBuilder.cs b/src/Components/Endpoints/src/Builder/RazorComponentsEndpointConventionBuilder.cs
@@ -18,27 +18,25 @@ public sealed class RazorComponentsEndpointConventionBuilder : IEndpointConventi
     private readonly RazorComponentDataSourceOptions _options;
     private readonly List<Action<EndpointBuilder>> _conventions;
     private readonly List<Action<EndpointBuilder>> _finallyConventions;
+    private readonly List<Action<ComponentApplicationBuilder>> _componentApplicationBuilderActions;
 
     internal RazorComponentsEndpointConventionBuilder(
         object @lock,
-        ComponentApplicationBuilder builder,
         IEndpointRouteBuilder endpointRouteBuilder,
         RazorComponentDataSourceOptions options,
         List<Action<EndpointBuilder>> conventions,
-        List<Action<EndpointBuilder>> finallyConventions)
+        List<Action<EndpointBuilder>> finallyConventions,
+        List<Action<ComponentApplicationBuilder>> componentApplicationBuilderActions)
     {
         _lock = @lock;
-        ApplicationBuilder = builder;
         EndpointRouteBuilder = endpointRouteBuilder;
         _options = options;
         _conventions = conventions;
         _finallyConventions = finallyConventions;
+        _componentApplicationBuilderActions = componentApplicationBuilderActions;
     }
 
-    /// <summary>
-    /// Gets the <see cref="ComponentApplicationBuilder"/> that is used to build the endpoints.
-    /// </summary>
-    internal ComponentApplicationBuilder ApplicationBuilder { get; }
+    internal List<Action<ComponentApplicationBuilder>> ComponentApplicationBuilderActions => _componentApplicationBuilderActions;
 
     internal string? ManifestPath { get => _options.ManifestPath; set => _options.ManifestPath = value; }
 
diff --git a/src/Components/Endpoints/src/Builder/RazorComponentsEndpointConventionBuilderExtensions.cs b/src/Components/Endpoints/src/Builder/RazorComponentsEndpointConventionBuilderExtensions.cs
@@ -30,7 +30,7 @@ public static RazorComponentsEndpointConventionBuilder AddAdditionalAssemblies(
 
         foreach (var assembly in assemblies)
         {
-            builder.ApplicationBuilder.AddAssembly(assembly);
+            builder.ComponentApplicationBuilderActions.Add(b => b.AddAssembly(assembly));
         }
         return builder;
     }
diff --git a/src/Components/Endpoints/test/Builder/RazorComponentsEndpointConventionBuilderExtensionsTest.cs b/src/Components/Endpoints/test/Builder/RazorComponentsEndpointConventionBuilderExtensionsTest.cs
@@ -245,15 +245,15 @@ public void MapRazorComponents_CanAddConventions_ToBlazorWebEndpoints(string fra
     private RazorComponentsEndpointConventionBuilder CreateRazorComponentsAppBuilder(IEndpointRouteBuilder endpointBuilder)
     {
         var builder = endpointBuilder.MapRazorComponents<App>();
-        builder.ApplicationBuilder.AddLibrary(new AssemblyComponentLibraryDescriptor(
+        builder.ComponentApplicationBuilderActions.Add(b => b.AddLibrary(new AssemblyComponentLibraryDescriptor(
             "App",
             [new PageComponentBuilder {
                 PageType = typeof(App),
                 RouteTemplates = ["/"],
                 AssemblyName = "App",
             }],
             []
-        ));
+        )));
         return builder;
     }
 
diff --git a/src/Components/Endpoints/test/HotReloadServiceTests.cs b/src/Components/Endpoints/test/HotReloadServiceTests.cs
@@ -23,9 +23,8 @@ public class HotReloadServiceTests
     public void UpdatesEndpointsWhenHotReloadChangeTokenTriggered()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder);
         var invoked = false;
 
         // Act
@@ -41,9 +40,8 @@ public void UpdatesEndpointsWhenHotReloadChangeTokenTriggered()
     public void AddNewEndpointWhenDataSourceChanges()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder);
 
         // Assert - 1
         var endpoint = Assert.IsType<RouteEndpoint>(
@@ -52,15 +50,17 @@ public void AddNewEndpointWhenDataSourceChanges()
         Assert.Equal("/server", endpoint.RoutePattern.RawText);
 
         // Act - 2
-        endpointDataSource.Builder.Pages.AddFromLibraryInfo("TestAssembly2", new[]
-        {
-            new PageComponentBuilder
+        endpointDataSource.ComponentApplicationBuilderActions.Add(
+            b => b.Pages.AddFromLibraryInfo("TestAssembly2", new[]
             {
-                AssemblyName = "TestAssembly2",
-                PageType = typeof(StaticComponent),
-                RouteTemplates = new List<string> { "/app/test" }
-            }
-        });
+                new PageComponentBuilder
+                {
+                    AssemblyName = "TestAssembly2",
+                    PageType = typeof(StaticComponent),
+                    RouteTemplates = new List<string> { "/app/test" }
+                }
+            }));
+
         HotReloadService.UpdateApplication(null);
 
         // Assert - 2
@@ -76,9 +76,8 @@ public void AddNewEndpointWhenDataSourceChanges()
     public void RemovesEndpointWhenDataSourceChanges()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder);
 
         // Assert - 1
         var endpoint = Assert.IsType<RouteEndpoint>(Assert.Single(endpointDataSource.Endpoints,
@@ -87,7 +86,7 @@ public void RemovesEndpointWhenDataSourceChanges()
         Assert.Equal("/server", endpoint.RoutePattern.RawText);
 
         // Act - 2
-        endpointDataSource.Builder.RemoveLibrary("TestAssembly");
+        endpointDataSource.ComponentApplicationBuilderActions.Add(b => b.RemoveLibrary("TestAssembly"));
         endpointDataSource.Options.ConfiguredRenderModes.Clear();
         HotReloadService.UpdateApplication(null);
 
@@ -100,9 +99,8 @@ public void RemovesEndpointWhenDataSourceChanges()
     public void ModifiesEndpointWhenDataSourceChanges()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder);
 
         // Assert - 1
         var endpoint = Assert.IsType<RouteEndpoint>(Assert.Single(endpointDataSource.Endpoints, e => e.Metadata.GetMetadata<RootComponentMetadata>() != null));
@@ -124,9 +122,8 @@ public void ModifiesEndpointWhenDataSourceChanges()
     public void NotifiesCompositeEndpointDataSource()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder);
         var compositeEndpointDataSource = new CompositeEndpointDataSource(
             new[] { endpointDataSource });
 
@@ -137,7 +134,7 @@ public void NotifiesCompositeEndpointDataSource()
         Assert.Equal("/server", compositeEndpoint.RoutePattern.RawText);
 
         // Act - 2
-        endpointDataSource.Builder.Pages.RemoveFromAssembly("TestAssembly");
+        endpointDataSource.ComponentApplicationBuilderActions.Add(b => b.Pages.RemoveFromAssembly("TestAssembly"));
         endpointDataSource.Options.ConfiguredRenderModes.Clear();
         HotReloadService.UpdateApplication(null);
 
@@ -148,37 +145,14 @@ public void NotifiesCompositeEndpointDataSource()
         Assert.Empty(compositePageEndpoints);
     }
 
-    private sealed class WrappedChangeTokenDisposable : IDisposable
-    {
-        public bool IsDisposed { get; private set; }
-        private readonly IDisposable _innerDisposable;
-
-        public WrappedChangeTokenDisposable(IDisposable innerDisposable)
-        { 
-            _innerDisposable = innerDisposable;
-        }
-
-        public void Dispose()
-        { 
-             IsDisposed = true;
-             _innerDisposable.Dispose();
-        }
-    }
-
     [Fact]
     public void ConfirmChangeTokenDisposedHotReload()
     {
         // Arrange
-        var builder = CreateBuilder(typeof(ServerComponent));
         var services = CreateServices(typeof(MockEndpointProvider));
-        var endpointDataSource = CreateDataSource<App>(builder, services);
-
-        WrappedChangeTokenDisposable wrappedChangeTokenDisposable = null;
-
-        endpointDataSource.SetDisposableChangeTokenAction = (IDisposable disposableChangeToken) => {
-            wrappedChangeTokenDisposable = new WrappedChangeTokenDisposable(disposableChangeToken); 
-            return wrappedChangeTokenDisposable;
-        };
+        var endpointDataSource = CreateDataSource<App>(services, ConfigureServerComponentBuilder, null);
+        var changeTokenSource = endpointDataSource.ChangeTokenSource;
+        var changeToken = endpointDataSource.GetChangeToken();
 
         var endpoint = Assert.IsType<RouteEndpoint>(Assert.Single(endpointDataSource.Endpoints, e => e.Metadata.GetMetadata<RootComponentMetadata>() != null));
         Assert.Equal("/server", endpoint.RoutePattern.RawText);
@@ -187,18 +161,21 @@ public void ConfirmChangeTokenDisposedHotReload()
         // Make a modification and then perform a hot reload.
         endpointDataSource.Conventions.Add(builder =>
             builder.Metadata.Add(new TestMetadata()));
+
         HotReloadService.UpdateApplication(null);
         HotReloadService.ClearCache(null);
 
         // Confirm the change token is disposed after ClearCache
-        Assert.True(wrappedChangeTokenDisposable.IsDisposed);
+        Assert.True(changeToken.HasChanged);
+        Assert.Throws<ObjectDisposedException>(() => changeTokenSource.Token);
     }
 
     private class TestMetadata { }
 
-    private ComponentApplicationBuilder CreateBuilder(params Type[] types)
+    private class TestAssembly : Assembly;
+
+    private static void ConfigureBuilder(ComponentApplicationBuilder builder, params Type[] types)
     {
-        var builder = new ComponentApplicationBuilder();
         builder.AddLibrary(new AssemblyComponentLibraryDescriptor(
             "TestAssembly",
             Array.Empty<PageComponentBuilder>(),
@@ -208,8 +185,11 @@ private ComponentApplicationBuilder CreateBuilder(params Type[] types)
                 ComponentType = t,
                 RenderMode = t.GetCustomAttribute<RenderModeAttribute>()
             }).ToArray()));
+    }
 
-        return builder;
+    private static void ConfigureServerComponentBuilder(ComponentApplicationBuilder builder)
+    {
+        ConfigureBuilder(builder, typeof(ServerComponent));
     }
 
     private IServiceProvider CreateServices(params Type[] types)
@@ -227,16 +207,21 @@ private IServiceProvider CreateServices(params Type[] types)
     }
 
     private static RazorComponentEndpointDataSource<TComponent> CreateDataSource<TComponent>(
-        ComponentApplicationBuilder builder,
         IServiceProvider services,
-        IComponentRenderMode[] renderModes = null)
+        Action<ComponentApplicationBuilder> configureBuilder = null,
+        IComponentRenderMode[] renderModes = null,
+        HotReloadService hotReloadService = null)
     {
         var result = new RazorComponentEndpointDataSource<TComponent>(
-            builder,
             new[] { new MockEndpointProvider() },
             new TestEndpointRouteBuilder(services),
             new RazorComponentEndpointFactory(),
-            new HotReloadService() { MetadataUpdateSupported = true });
+            hotReloadService ?? new HotReloadService() { MetadataUpdateSupported = true });
+
+        if (configureBuilder is not null)
+        {
+            result.ComponentApplicationBuilderActions.Add(configureBuilder);
+        }
 
         if (renderModes != null)
         {
diff --git a/src/Components/Endpoints/test/RazorComponentEndpointDataSourceTest.cs b/src/Components/Endpoints/test/RazorComponentEndpointDataSourceTest.cs

Original file line number	Diff line number	Diff line change
`@@ -17,9 +17,14 @@ internal class RazorComponentEndpointDataSourceFactory(`
`17`	`17`	`{`
`18`	`18`	`public RazorComponentEndpointDataSource<TRootComponent> CreateDataSource<[DynamicallyAccessedMembers(Component)] TRootComponent>(IEndpointRouteBuilder endpoints)`
`19`	`19`	`{`
`20`		`- var builder = ComponentApplicationBuilder.GetBuilder<TRootComponent>() ??`
`21`		`- DefaultRazorComponentApplication<TRootComponent>.Instance.GetBuilder();`
	`20`	`+ var dataSource = new RazorComponentEndpointDataSource<TRootComponent>(providers, endpoints, factory, hotReloadService);`
`22`	`21`
`23`		`- return new RazorComponentEndpointDataSource<TRootComponent>(builder, providers, endpoints, factory, hotReloadService);`
	`22`	`+ dataSource.ComponentApplicationBuilderActions.Add(builder =>`
	`23`	`+ {`
	`24`	`+ var assembly = typeof(TRootComponent).Assembly;`
	`25`	`+ IRazorComponentApplication.GetBuilderForAssembly(builder, assembly);`
	`26`	`+ });`
	`27`	`+`
	`28`	`+ return dataSource;`
`24`	`29`	`}`
`25`	`30`	`}`
Original file line number	Diff line number	Diff line change
`@@ -30,7 +30,7 @@ public static RazorComponentsEndpointConventionBuilder AddAdditionalAssemblies(`
`30`	`30`
`31`	`31`	`foreach (var assembly in assemblies)`
`32`	`32`	`{`
`33`		`- builder.ApplicationBuilder.AddAssembly(assembly);`
	`33`	`+ builder.ComponentApplicationBuilderActions.Add(b => b.AddAssembly(assembly));`
`34`	`34`	`}`
`35`	`35`	`return builder;`
`36`	`36`	`}`