API Proposal: ServerComponentsEndpointOptions.ConfigureConnection

[javiercn]

Background and Motivation

Users of AddInteractiveServerRenderMode had no clean way to configure the underlying SignalR HttpConnectionDispatcherOptions. Previously, users had to resort to workarounds using metadata inspection to access properties like CloseOnAuthenticationExpiration. The old MapBlazorHub had overloads accepting dispatcher options, but AddInteractiveServerRenderMode did not expose this configuration surface.

Source: PR #63825, fixes #63520.

Proposed API

namespace Microsoft.AspNetCore.Components.Server;

public class ServerComponentsEndpointOptions
{
+    public Action<HttpConnectionDispatcherOptions>? ConfigureConnection { get; set; }
}

Usage Examples

app.MapRazorComponents<App>()
    .AddInteractiveServerRenderMode(options =>
    {
        options.ConfigureConnection = dispatcherOptions =>
        {
            dispatcherOptions.CloseOnAuthenticationExpiration = true;
            dispatcherOptions.AllowStatefulReconnects = true;
            dispatcherOptions.ApplicationMaxBufferSize = 1024 * 1024;
        };
    });

Alternative Designs

The workaround was inspecting metadata via .Add(e => { var opts = e.Metadata.OfType<HttpConnectionDispatcherOptions>().FirstOrDefault(); ... }). This was not type-safe, hard to discover, fragile, and inconsistent with MapBlazorHub.

Risks

None — additive property, null by default preserves existing behavior. Zero overhead when not used.

[dotnet-policy-service]

Thank you for submitting this for API review. This will be reviewed by @dotnet/aspnet-api-review at the next meeting of the ASP.NET Core API Review group. Please ensure you take a look at the API review process documentation and ensure that:

• The PR contains changes to the reference-assembly that describe the API change. Or, you have included a snippet of reference-assembly-style code that illustrates the API change.
• The PR describes the impact to users, both positive (useful new APIs) and negative (breaking changes).
• Someone is assigned to "champion" this change in the meeting, and they understand the impact and design of the change.

[github-actions]

Triage Summary

Area: area-blazor ✅ (already labeled — API proposal for ServerComponentsEndpointOptions in Microsoft.AspNetCore.Components.Server, which is the Blazor server-side rendering area)
Type: api-proposal — This is a formal API addition proposal following the standard API proposal template, adding ConfigureConnection property to ServerComponentsEndpointOptions.

Potential Duplicates

• [Blazor] Provide access to the underlying SignalR HttpConnectionDispatcherOptions in AddInteractiveServerRenderMode #63520 - [Blazor] Provide access to the underlying SignalR HttpConnectionDispatcherOptions in AddInteractiveServerRenderMode (similarity: high — this is the original feature request that this API proposal directly addresses, as referenced in the issue body)
• Support configuring SignalR hub option with Blazor interactive server rendering #54080 - Support configuring SignalR hub option with Blazor interactive server rendering (similarity: medium — same underlying ask but slightly different scope)

Notes

• The issue is filed by a repo member (javiercn) and already carries area-blazor and api-ready-for-review labels, so it is well-formed.
• [Blazor] Provide access to the underlying SignalR HttpConnectionDispatcherOptions in AddInteractiveServerRenderMode #63520 is the originating request; this issue is the formal API proposal to resolve it (referencing PR [Blazor] Provide access to HttpConnectionDispatcherOptions in AddInteractiveServerRenderMode #63825).
• No regression detected — this is a new API addition with no breaking changes.

Generated by Issue Triage Agent for dotnet/aspnetcore for issue #66387 · ● 201.3K · ◷

[MihuBot]

I'm a bot. Here are possible related and/or duplicate issues (I may be wrong):

• Support configuring SignalR hub option with Blazor interactive server rendering #54080
• .NET 8 Blazor - Cannot Set CloseOnAuthenticationExpiration With Global Interactive Rendering / InteractiveServerRenderMode #54296

[halter73]

API Review Notes:

• Are we sure we want nested options?
  • We don't want to use the general options pattern, because this is called per-endpoint after DI is fully configured.
  • Can we hoist the ServerComponentsEndpointOptions, so it's just a direct property rather than an Action<HttpConnectionDispatcherOptions>. We don't think so, because it's called multiple times HttpConnectionDispatcherOptions
  • If it were possible to hoist, we would do so.
• ConfigureConnection vs ConfigureConnectionOptions vs ConfigureHttpConnection.

API Approved!

namespace Microsoft.AspNetCore.Components.Server;

public class ServerComponentsEndpointOptions
{
+    public Action<HttpConnectionDispatcherOptions>? ConfigureConnection { get; set; }
}