Add Map implementation with overload for InferMetadata and CreateRequestDelegate #46163
Description
Background and Motivation
For the purposes of the request delegate generator, we want to be able to invoke the logic in the RouteEndpointDataSource but provide a custom implementation of a Map method that will allow the user to pass custom delegates for inferring metadata and producing a request delegate. The source generator will call this overload with implementations generated at compile time to circumvent calling APIs that use runtime code generation.
Proposed API
public static class GeneratedRouteEndpointBuilderExtensions
{
public static Microsoft.AspNetCore.Builder.RouteHandlerBuilder Map(
this Microsoft.AspNetCore.Routing.IEndpointRouteBuilder routes,
string pattern,
System.Delegate handler,
IEnumerable<string> httpMethods,
Func<MethodInfo, RequestDelegateFactoryOptions?, RequestDelegateMetadataResult> populateMetadata,
Func<Delegate, RequestDelegateFactoryOptions, RequestDelegateMetadataResult?, RequestDelegateResult> createRequestDelegate)
{
return routes
.GetOrAddRouteEndpointDataSource()
.AddRouteHandler(RoutePatternFactory.Parse(pattern),
handler,
httpMethods,
isFallback: false,
populateMetadata,
createRequestDelegate);
}Usage Examples
[GeneratedCode]
internal static Microsoft.AspNetCore.Builder.RouteHandlerBuilder MapPut(
this Microsoft.AspNetCore.Routing.IEndpointRouteBuilder endpoints,
[System.Diagnostics.CodeAnalysis.StringSyntax("Route")] string pattern,
Delegate handler)
{
var populateMetadata = (methodInfo, options) => {
var metadata = new List<object>();
// ...
return new RequestDelegateMetadataResult { EndpointMetadata = AsReadOnlyList(metadata) };
};
var createRequestDelegate = (del, options, requestDelegateMetadataResult) => {
// ...
return new RequestDelegateResult(finalRequestDelegate, requestDelegateMetadataResult.Metadata);
};
return Map(endpoints, pattern, handler, GetVerb, populateMetadata, createRequestDelegate);
}