[Blazor] Startup APIs API review

[javiercn]

Background and motivation

These set of APIs define how Razor Component Endpoints are configured in DI and how endpoints to server Razor Component Applications are defined.

Proposed APIs

+static Microsoft.Extensions.DependencyInjection.RazorComponentsServiceCollectionExtensions.AddRazorComponents(this Microsoft.Extensions.DependencyInjection.IServiceCollection! services) -> Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder!
+static Microsoft.Extensions.DependencyInjection.RazorComponentsServiceCollectionExtensions.AddRazorComponents(this Microsoft.Extensions.DependencyInjection.IServiceCollection! services, System.Action<Microsoft.Extensions.DependencyInjection.RazorComponentOptions!>! setupAction) -> Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder!
+Microsoft.AspNetCore.Components.WebAssembly.Server.TargetPickerUi.DisplayFirefox(Microsoft.AspNetCore.Http.HttpContext! context) -> System.Threading.Tasks.Task!
+Microsoft.Extensions.DependencyInjection.RazorComponentsBuilderExtensions
+static Microsoft.Extensions.DependencyInjection.RazorComponentsBuilderExtensions.AddWebAssemblyComponents(this Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder! builder, System.Action<Microsoft.AspNetCore.Components.Endpoints.WebAssemblyComponentsEndpointOptions!>? configure = null) -> Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder!
+Microsoft.Extensions.DependencyInjection.RazorComponentsBuilderExtensions
+static Microsoft.Extensions.DependencyInjection.RazorComponentsBuilderExtensions.AddServerComponents(this Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder! builder, System.Action<Microsoft.AspNetCore.Components.Server.CircuitOptions!>? configure = null) -> Microsoft.AspNetCore.Components.Endpoints.IRazorComponentsBuilder!
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder.Add(System.Action<Microsoft.AspNetCore.Builder.EndpointBuilder!>! convention) -> void
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder.AddServerRenderMode() -> Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder!
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder.AddWebAssemblyRenderMode() -> Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder!
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder.ApplicationBuilder.get -> Microsoft.AspNetCore.Components.Discovery.ComponentApplicationBuilder!
+Microsoft.AspNetCore.Builder.RazorComponentEndpointConventionBuilder.Finally(System.Action<Microsoft.AspNetCore.Builder.EndpointBuilder!>! finallyConvention) -> void
+Microsoft.AspNetCore.Builder.RazorComponentsEndpointRouteBuilderExtensions
+Microsoft.AspNetCore.Components.Endpoints.WebAssemblyComponentsEndpointOptions
+Microsoft.AspNetCore.Components.Endpoints.WebAssemblyComponentsEndpointOptions.PathPrefix.get -> Microsoft.AspNetCore.Http.PathString
+Microsoft.AspNetCore.Components.Endpoints.WebAssemblyComponentsEndpointOptions.PathPrefix.set -> void
+Microsoft.AspNetCore.Components.Endpoints.WebAssemblyComponentsEndpointOptions.WebAssemblyComponentsEndpointOptions() -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.FormMappingUseCurrentCulture.get -> bool
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.FormMappingUseCurrentCulture.set -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingCollectionSize.get -> int
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingCollectionSize.set -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingErrorCount.get -> int
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingErrorCount.set -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingKeySize.get -> int
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingKeySize.set -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingRecursionDepth.get -> int
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.MaxFormMappingRecursionDepth.set -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentOptions.RazorComponentOptions() -> void
+Microsoft.Extensions.DependencyInjection.RazorComponentsServiceCollectionExtensions

Usage examples

Canonical scenarios

Server Side Rendered components

services.AddRazorComponents();


builder.MapRazorComponents<App>();

Server Side rendering + Interactive server components

services.AddRazorComponents()
  .AddServerComponents();


builder.MapRazorComponents<App>()
  .AddServerRenderMode();

Server Side rendering + Interactive webassembly components

services.AddRazorComponents()
  .AddWebAssemblyComponents();


builder.MapRazorComponents<App>()
  .AddWebAssemblyRenderMode();

Server Side rendering + Interactive server and webassembly components

services.AddRazorComponents()
  .AddServerComponents()
  .AddWebAssemblyComponents();

builder.MapRazorComponents<App>()
  .AddServerRenderMode()
  .AddWebAssemblyRenderMode();

Other advanced scenarios

Configuring global options

services.AddRazorComponents(options =>
{
  options.FormMappingUseCurrentCulture = false;
  options.MaxFormMappingCollectionSize = 100;
  options.MaxFormMappingErrorCount = 100;
  options.MaxFormMappingKeySize = 100;
  options.MaxFormMappingRecursionDepth = 100;
});

Configuring server component options

services.AddRazorComponents()
  .AddServerComponents(options =>
  {
    options.MaxBufferedUnacknowledgedRenderBatches = 5;
    ...
    // These are not new APIs
  });

services.AddRazorComponents()
  .AddServerComponents()
  .AddHubOptions(); // Configure options specific to the SignalR Hub (this is the equivalent of services.AddServerSideBlazor().AddHubOptions(opt => ...))

Risks

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.

[halter73]

API Review Notes:

• What "builder" are we using in builder.MapRazorComponents<App>(); IEndpointRouteBuilder, so WebApplication or app typically.
• What's the failure mode if AddRazorComponents without MapRazorComponents or vice versa?
  • We give an error for missing services, but not for "extra" services because there might be extra branches that are hard to analyze.
• Could we make AddServerRenderMode and AddWebAssemblyRenderMode automatic based on whether AddServerComponents and/or AddWebAssemblyComponents were added?
  • This might be hard because of branching
• AddServerRenderMode and AddWebAssemblyComponents are not extension methods because they need to run internal logic before you would typically add metadata to an endpoint.
• What about the name setupAction?
  • This copies MVC. We think we should switch to single overload with a default value: Action<RazorComponentOptions> configure = null for consitency with the other options callbacks we're adding.
• What about `WebAssemblyComponentsEndpointOptions
• What does PathPrefix do?
  • Is this referencing a filesystem path? Yes. this is a relative path in the wwwroot. This is why we cannot just rely on route groups.
  • Can we come up with a better name? Not easily. Maybe FrameworkFilesPathsPrefix like in @MackinnonBuck's original PR? Or ContentPathPrefix?
  • It is used in routing, so PathString makes sense as a type.
• Should form options like FormMappingUseCurrentCulture be a global option, or should we make it per-form?
  • FormMappingUseCurrentCulture defaults to false. If you want complete control, you could manually set it to true and configure the right culture.
  • Let's remove FormMappingUseCurrentCulture because it's a footgun.
• Can we share form options with minimal APIs?
  • That'd be nice, but we need a design.

Here is our progress so far. In the next meeting will discuss a few more minor things like whether IRazorComponentsBuilder should move to a different namespace, whether RazorComponentOptions should move to a different namespace, if we should seal more classes, and alternate names for the two Microsoft.Extensions.DependencyInjection.RazorComponentsBuilderExtensions classes.

// Microsoft.AspNetCore.Components.Endpoints.dll
namespace Microsoft.AspNetCore.Components.Endpoints;
 
public interface IRazorComponentsBuilder
{
    public IServiceCollection Services { get; }
}

public sealed class WebAssemblyComponentsEndpointOptions
{
    public PathString PathPrefix { get; set; }
}

namespace Microsoft.AspNetCore.Builder;

public class RazorComponentEndpointConventionBuilder : IEndpointConventionBuilder
{
    // internal ctor

    public ComponentApplicationBuilder ApplicationBuilder { get; }

    public RazorComponentEndpointConventionBuilder AddWebAssemblyRenderMode();
    public RazorComponentEndpointConventionBuilder AddServerRenderMode();

    public void Add(Action<EndpointBuilder> convention);
    public void Finally(Action<EndpointBuilder> finallyConvention);
}

namespace Microsoft.Extensions.DependencyInjection;

public static class RazorComponentsServiceCollectionExtensions
{
    public static IRazorComponentsBuilder AddRazorComponents(this IServiceCollection services, Action<RazorComponentOptions>? configure = null);
}

public class RazorComponentOptions
{
    public int MaxFormMappingCollectionSize { get; set; }
    public int MaxFormMappingRecursionDepth { get; set; }
    public int MaxFormMappingErrorCount { get; set; }
    public int MaxFormMappingKeySize { get; set; }
}

// Microsoft.AspNetCore.Components.WebAssembly.Server.dll
namespace Microsoft.Extensions.DependencyInjection;

public static class RazorComponentsBuilderExtensions
{
    public static IRazorComponentsBuilder AddWebAssemblyComponents(this IRazorComponentsBuilder builder, Action<WebAssemblyComponentsEndpointOptions>? configure = null)
}

// Microsoft.AspNetCore.Components.Server.dll
namespace Microsoft.Extensions.DependencyInjection;

public static class RazorComponentsBuilderExtensions
{
    public static IRazorComponentsBuilder AddServerComponents(this IRazorComponentsBuilder builder, Action<CircuitOptions>? configure = null);
}

[javiercn]

// Microsoft.AspNetCore.Components.Endpoints.dll
-namespace Microsoft.AspNetCore.Components.Endpoints;
+namespace Microsoft.Extensions.DependencyInjection;

public interface IRazorComponentsBuilder
{
    public IServiceCollection Services { get; }
}

-namespace Microsoft.AspNetCore.Components.Endpoints;
+namespace Microsoft.AspNetCore.Components.WebAssembly.Server;

+public sealed class WebAssemblyComponentsEndpointsOptions
{
    public PathString PathPrefix { get; set; }
}
// Move to `WebAssembly.Server` if possible

namespace Microsoft.AspNetCore.Builder;

+public sealed class RazorComponentsEndpointConventionBuilder : IEndpointConventionBuilder
{
    // internal ctor

-    public ComponentApplicationBuilder ApplicationBuilder { get; }

    public RazorComponentsEndpointConventionBuilder AddWebAssemblyRenderMode();
    public RazorComponentsEndpointConventionBuilder AddServerRenderMode();

    public void Add(Action<EndpointBuilder> convention);
    public void Finally(Action<EndpointBuilder> finallyConvention);
}

namespace Microsoft.Extensions.DependencyInjection;

public static class RazorComponentsServiceCollectionExtensions
{
-    public static IRazorComponentsBuilder AddRazorComponents(this IServiceCollection services)
+    public static IRazorComponentsBuilder AddRazorComponents(this IServiceCollection services, Action<RazorComponentsOptions>? configure = null);
}

-namespace Microsoft.Extensions.DependencyInjection;
+namespace Microsoft.AspNetCore.Components.Endpoints;

+ public sealed class RazorComponentsOptions
{
    public int MaxFormMappingCollectionSize { get; set; }
    public int MaxFormMappingRecursionDepth { get; set; }
    public int MaxFormMappingErrorCount { get; set; }
    public int MaxFormMappingKeySize { get; set; }
-    public bool FormMappingUseCurrentCulture { get; set; }
}

// Microsoft.AspNetCore.Components.WebAssembly.Server.dll
namespace Microsoft.Extensions.DependencyInjection;

+public static class WebAssemblyRazorComponentsBuilderExtensions
{
+    public static IRazorComponentsBuilder AddWebAssemblyComponents(this IRazorComponentsBuilder builder)
}

// Microsoft.AspNetCore.Components.Server.dll
namespace Microsoft.Extensions.DependencyInjection;

+public static class ServerRazorComponentsBuilderExtensions
{
    public static IRazorComponentsBuilder AddServerComponents(this IRazorComponentsBuilder builder, Action<CircuitOptions>? configure = null);
}

[halter73]

Post API Review fixup notes:

• We do not have the API updates reflected in this issue yet, but @javiercn plans to add them.
• What do we think about the proposed RazorComponentOptions to RazorComponentServerOptions rename (made offline)?
  • Will it be confused with "Blazor Server" with a SignalR circuit?
  • RazorComponentServiceOptions?
• Do we want the RazorComponentsEndpointConventionBuilder.AddRenderMode(IComponentRenderMode renderMode) to exist for use by extension method?
  • Could we make AddServerRenderMode and AddAssemblyRenderMode normal methods rather than extension methods that call AddRenderMode?
    • It would prevent us for adding SignalR specific options to AddServerRenderMode because of layering.

To be continued.