[Blazor] Add WithStaticAssets extension for IEndpointConventionBuilder #63820

Copilot · 2025-09-25T11:38:09Z

Adds a new WithStaticAssets extension method that works with any IEndpointConventionBuilder, enabling endpoints to attach ResourceCollection metadata.

Description

This PR introduces EndpointConventionBuilderResourceCollectionExtensions.WithStaticAssets() that extends any IEndpointConventionBuilder to attach ResourceCollection metadata to endpoints.

Key Features

Extends any IEndpointConventionBuilder: Works with MapGroup(), MapGet(), MapPost(), and other endpoint convention builders
Requires IEndpointRouteBuilder parameter: Takes an IEndpointRouteBuilder parameter to access static assets data sources (necessary because RouteGroupBuilder doesn't expose its parent's data sources)
Lazy initialization: Uses a private nested ResourceCollectionConvention class that lazily resolves collections on the first endpoint
Performance optimized: Caches and reuses the same ResourceCollectionResolver, ResourceAssetCollection, ResourcePreloadCollection, and ImportMapDefinition instances across all endpoints
Duplicate detection: Checks for existing ResourceAssetCollection metadata to avoid duplicates
Optional manifest path: Supports custom static asset manifest paths

Usage Examples

With MapGet:

app.MapGet("/page", () => new RazorComponentResult<MyComponent>())
   .WithStaticAssets(app);

With MapGroup:

var group = app.MapGroup("/api");
group.WithStaticAssets(app);
group.MapGet("/endpoint", () => "test");

With custom manifest:

app.MapGet("/admin", () => new RazorComponentResult<AdminComponent>())
   .WithStaticAssets(app, "custom-manifest.json");

Implementation Details

File named EndpointConventionBuilderResourceCollectionExtensions.cs matching the class name
Private nested ResourceCollectionConvention class encapsulates lazy initialization logic
Convention captures the IEndpointRouteBuilder parameter to resolve static assets
All expensive operations (resolver creation, collection resolution) happen once and are cached
Follows the same pattern used in MVC's ControllerActionEndpointConventionBuilderResourceCollectionExtensions

Testing

✅ All 6 unit tests pass
✅ All existing tests in Components.Endpoints pass
✅ Build succeeds with no warnings
✅ Public API changes validated

Test Coverage

Tests use real routing APIs (MapGroup() and MapGet()) without reflection, triggering endpoint building through DataSources.Endpoints:

WithStaticAssets_DoesNotAddResourceCollection_ToEndpoints_NoStaticAssetsMapped: Verifies no metadata is added when static assets aren't mapped
WithStaticAssets_AddsResourceCollection_ToEndpoints_WithMatchingManifest: Verifies metadata (ResourceAssetCollection, ResourcePreloadCollection, ImportMapDefinition) is added when manifest matches
WithStaticAssets_DoesNotAddResourceCollection_WhenAlreadyExists: Verifies duplicate metadata is not added when collection already exists
WithStaticAssets_AddsResourceCollection_ToEndpoints_DefaultManifest: Verifies default manifest works correctly
WithStaticAssets_OnMapGet_AddsResourceCollection_WhenEndpointBuilderImplementsIEndpointRouteBuilder: Verifies WithStaticAssets works when called on MapGet result
WithStaticAssets_OnMapGetInGroup_AddsResourceCollection: Verifies MapGet inside a group with WithStaticAssets receives metadata

Original prompt

This section details on the original issue you should resolve

<issue_title>[Blazor] Provide a helper to attach ResourceCollection metadata to other endpoints</issue_title>
<issue_description>This will be useful in the context of RazorComponentResult

#58937 (comment)</issue_description>

<agent_instructions>We want to provide a helper like that doesn't use RazorComponentsEndpointConventionBuilder but instead just extends IEndpointRouteBuilder

aspnetcore/src/Components/Endpoints/src/Builder/RazorComponentsEndpointConventionBuilderExtensions.cs

Lines 50 to 64 in 063ba34

public static RazorComponentsEndpointConventionBuilder WithStaticAssets(

this RazorComponentsEndpointConventionBuilder builder,

string? manifestPath = null)

{

ArgumentNullException.ThrowIfNull(builder);

builder.ManifestPath = manifestPath;

if (!builder.ResourceCollectionConventionRegistered)

{

builder.ResourceCollectionConventionRegistered = true;

var convention = new ResourceCollectionConvention(new ResourceCollectionResolver(builder.EndpointRouteBuilder));

builder.BeforeCreateEndpoints += convention.OnBeforeCreateEndpoints;

builder.Add(convention.ApplyConvention);

}

return builder;

It can be simplified to only do the following. If not done, it should check there isn't a resource collection already on the metadata.
            var convention = new ResourceCollectionConvention(new ResourceCollectionResolver(builder.EndpointRouteBuilder));
            builder.Add(convention.ApplyConvention);
```</agent_instructions>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

Fixes #63398

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Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

…8916

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

Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

src/Components/Endpoints/src/Builder/EndpointRouteBuilderResourceCollectionExtensions.cs

Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

src/Components/Endpoints/src/Builder/EndpointRouteBuilderResourceCollectionExtensions.cs

Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

Copilot

Pull request overview

This PR introduces a new WithStaticAssets() extension method for IEndpointConventionBuilder that enables attaching static asset metadata (ResourceCollection, ImportMap, etc.) to any endpoint convention builder. This is particularly useful for RouteGroupBuilder scenarios where developers want to add static asset support without requiring explicit passing of the route builder.

Key Changes:

Adds EndpointConventionBuilderResourceCollectionExtensions.WithStaticAssets() that works with any IEndpointConventionBuilder
Automatically detects when the builder also implements IEndpointRouteBuilder and uses it to resolve static assets
Supports optional manifestPath parameter for custom static asset manifests
Includes duplicate detection to avoid adding metadata when it already exists

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
`src/Components/Endpoints/src/Builder/EndpointRouteBuilderResourceCollectionExtensions.cs`	New extension class providing `WithStaticAssets()` method that adds ResourceCollection metadata to endpoints by checking if the convention builder also implements IEndpointRouteBuilder
`src/Components/Endpoints/test/Builder/EndpointConventionBuilderResourceCollectionExtensionsTest.cs`	Test suite with 4 tests covering scenarios: no static assets mapped, matching manifest, avoiding duplicates, and default manifest
`src/Components/Endpoints/src/PublicAPI.Unshipped.txt`	Public API surface addition documenting the new extension method

src/Components/Endpoints/src/Builder/EndpointConventionBuilderResourceCollectionExtensions.cs

src/Components/Endpoints/src/Builder/EndpointRouteBuilderResourceCollectionExtensions.cs

src/Components/Endpoints/src/Builder/EndpointConventionBuilderResourceCollectionExtensions.cs

...mponents/Endpoints/test/Builder/EndpointConventionBuilderResourceCollectionExtensionsTest.cs

@javiercn

Fixed typos and logic errors in @javiercn's cleanup commit: - Fixed typo: IRouteEndpointBuilder -> IEndpointRouteBuilder - Fixed logic: changed else to separate if for adding metadata - Updated tests to use real MapGroup API and RouteGroupBuilder - Made TestEndpointBuilder implement IEndpointRouteBuilder for proper testing - Tests now explicitly demonstrate MapGroup usage as requested Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

Copilot · 2025-12-19T17:53:23Z

@copilot build the code with my changes and ensure the tests pass. Use MapGet and MapGroup explicitly on the tests and write a summary of the tests you added after you are done.

Fixed compilation errors and updated tests in commit c2be237.

All 4 tests now pass and use MapGroup() explicitly:

WithStaticAssets_DoesNotAddResourceCollection_ToEndpoints_NoStaticAssetsMapped: Verifies no metadata is added when static assets aren't mapped
WithStaticAssets_AddsResourceCollection_ToEndpoints_WithMatchingManifest: Verifies ResourceAssetCollection, ResourcePreloadCollection, and ImportMapDefinition are added when manifest matches
WithStaticAssets_DoesNotAddResourceCollection_WhenAlreadyExists: Verifies duplicate metadata is not added
WithStaticAssets_AddsResourceCollection_ToEndpoints_DefaultManifest: Verifies default manifest works correctly

Tests use real MapGroup() API from routing and RouteGroupBuilder, demonstrating real-world usage patterns.

...mponents/Endpoints/test/Builder/EndpointConventionBuilderResourceCollectionExtensionsTest.cs

Added 2 new tests that use MapGet: - WithStaticAssets_OnMapGet_AddsResourceCollection_WhenEndpointBuilderImplementsIEndpointRouteBuilder: Verifies that WithStaticAssets works when called on MapGet result - WithStaticAssets_OnMapGetInGroup_AddsResourceCollection: Verifies that MapGet inside a group with WithStaticAssets receives metadata All 6 tests now pass. Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

...mponents/Endpoints/test/Builder/EndpointConventionBuilderResourceCollectionExtensionsTest.cs

Updated all tests to: - Remove reflection-based ApplyConventions helper methods - Remove TestEndpointBuilder class that combined EndpointBuilder and IEndpointRouteBuilder - Use real MapGroup() and MapGet() calls that create actual endpoints - Access endpoints through DataSources.Endpoints which triggers endpoint building Tests now follow the same pattern as routing tests but are currently failing. The issue appears to be that conventions aren't being applied when endpoints are built. Need guidance on correct implementation approach. Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

dotnet-policy-service · 2025-12-29T17:10:10Z

Looks like this PR hasn't been active for some time and the codebase could have been changed in the meantime.
To make sure no conflicting changes have occurred, please rerun validation before merging. You can do this by leaving an /azp run comment here (requires commit rights), or by simply closing and reopening.

ilonatommy · 2026-01-02T08:50:59Z

It has connected test failures in Microsoft.AspNetCore.Components.Endpoints.Tests

javiercn · 2026-01-02T11:09:33Z

It has connected test failures in Microsoft.AspNetCore.Components.Endpoints.Tests

Yes. I need to force it to do the tests write, but I'll have to clone and do it from VS Code where its easier for me to correct it.

javiercn · 2026-01-07T17:27:37Z

@copilot there are some errors:

Build Errors

aspnetcore-ci

.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...
.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...
.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...
Microsoft.AspNetCore.Components.Endpoints.Tests.Builder.EndpointConventionBuilderResourceCollectionExtensionsTest.WithStaticAssets_OnMapGetInGroup_AddsResourceCollection:1 Assert.NotNull() Failure: Value is null
Microsoft.AspNetCore.Components.Endpoints.Tests.Builder.EndpointConventionBuilderResourceCollectionExtensionsTest.WithStaticAssets_AddsResourceCollection_ToEndpoints_WithMatchingManifest:1 Assert.NotNull() Failure: Value is null
Microsoft.AspNetCore.Components.Endpoints.Tests.Builder.EndpointConventionBuilderResourceCollectionExtensionsTest.WithStaticAssets_OnMapGet_AddsResourceCollection_WhenEndpointBuilderImplementsIEndpointRouteBuilder:1 Assert.NotNull() Failure: Value is null
Microsoft.AspNetCore.Components.Endpoints.Tests.Builder.EndpointConventionBuilderResourceCollectionExtensionsTest.WithStaticAssets_AddsResourceCollection_ToEndpoints_DefaultManifest:1 Assert.NotNull() Failure: Value is null

aspnetcore-ci (Build Tests: Helix x64 Subset 2)

.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...
.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...
.packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets:91 .packages\microsoft.dotnet.helix.sdk\11.0.0-beta.25603.106\tools\Microsoft.DotNet.Helix.Sdk.MultiQueue.targets(91,5): error : (NETCORE_ENGINEERING_TELEMETRY=Test) Work item Microsoft.AspNetCore.Com...

Summary

10 build error(s)
0 test failure(s)

- Restored correct implementation that checks if builder implements IEndpointRouteBuilder - Captures IEndpointRouteBuilder when builder implements it (like RouteGroupBuilder) - Uses captured route builder in convention to resolve static assets - Convention now lazily initializes resolver and collections on first endpoint Tests still failing - collection is null, likely due to IsRegistered or ResolveResourceCollection issues. Need to investigate further. Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

Copilot · 2026-01-07T17:38:59Z

@copilot there are some errors:

Build Errors

...

Working on fixing the test failures. The implementation now correctly checks if the builder implements IEndpointRouteBuilder and captures it, but 4 tests are still failing because the resource collection is null. Investigating the IsRegistered/ResolveResourceCollection calls to identify the root cause. Commit 17c395f has the current state.

@copilot there are some errors:

Build Errors

...

Fixed in commit 055795d. Changed the API to require an IEndpointRouteBuilder parameter, which solves the issue where RouteGroupBuilder's DataSources don't include the outer builder's static assets data source. All 6 tests now pass successfully.

Changed the API to require an IEndpointRouteBuilder parameter instead of checking if the builder implements it. This solves the RouteGroupBuilder issue where the group's DataSources don't include the outer builder's static assets data source. Users now call it like: - `app.MapGet("/page", () => ...).WithStaticAssets(app)` - `var group = app.MapGroup("/api"); group.WithStaticAssets(app);` All 6 tests now pass! Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

javiercn · 2026-01-07T18:36:39Z

/azp run aspnetcore-ci

azure-pipelines · 2026-01-07T18:36:48Z

Azure Pipelines successfully started running 1 pipeline(s).

Initial plan

c0a3fb5

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Add EndpointConventionBuilderResourceCollectionExtensions helper

82829a4

Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>

Copilot AI changed the title ~~[WIP] [Blazor] Provide a helper to attach ResourceCollection metadata to other endpoints~~ [Blazor] Add WithStaticAssets extension for IEndpointConventionBuilder Sep 25, 2025

Copilot AI requested a review from javiercn September 25, 2025 11:55

Copilot finished work on behalf of javiercn September 25, 2025 11:55

Merge branch 'main' into copilot/fix-88eedca1-66b9-4ca9-936c-4abf704a…

9265687

…8916

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Clean up PublicAPI.Unshipped.txt to only include new API

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Simplify WithStaticAssets to not require IEndpointRouteBuilder parameter

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Combine duplicate checks into single if statement

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	public static RazorComponentsEndpointConventionBuilder WithStaticAssets(
	this RazorComponentsEndpointConventionBuilder builder,
	string? manifestPath = null)
	{
	ArgumentNullException.ThrowIfNull(builder);
	builder.ManifestPath = manifestPath;
	if (!builder.ResourceCollectionConventionRegistered)
	{
	builder.ResourceCollectionConventionRegistered = true;
	var convention = new ResourceCollectionConvention(new ResourceCollectionResolver(builder.EndpointRouteBuilder));
	builder.BeforeCreateEndpoints += convention.OnBeforeCreateEndpoints;
	builder.Add(convention.ApplyConvention);
	}

	return builder;

[Blazor] Add WithStaticAssets extension for IEndpointConventionBuilder #63820

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[Blazor] Add WithStaticAssets extension for IEndpointConventionBuilder #63820

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Build Errors

aspnetcore-ci

aspnetcore-ci (Build Tests: Helix x64 Subset 2)

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