New Type of Resource Provider Adding the Idea of Resource Locators

[Stekeblad]

This pull request adds two new projects to the solution:

• Sample.Stekeblad.PartialStaticSite: A sample project showing of the other new project,
• AspNetStaticContrib.Stekeblad

Contrib.Stekeblad adds a new resource provider, LocatingStaticResourcesInfoProvider that derives from StaticResourcesInfoProvider. It introduces support for adding any number of "Resource locators" to the provider.

Resource locators is a feature added in the new project that package consumers can implement to in a dynamic way find and list content in their application using any registered services and features. The ability to use services was previously limited.

This PR also includes two Resource Locators:

• ActionDescriptorPageResourceLocator: Locates Compiled Razor Pages, first suggested in Improve logic for locating Razor Pages #20
• SitemapPageResourceLocator: Locates pages by retrieving the sitemap(s)

There is also a small fix to the newly added processStartSignal that corrects an issue where it could lock the entire application until signalTimeoutSeconds had elapsed.

[ZarehD]

Good work, @Stekeblad!

Some questions and corrections...

File: src/AspNetStaticContrib.Stekeblad/Extensions/IHostExtensions.cs

• Line 41: if (!empoweredProvider.Resources.Any()) throw... Why? AspNetStatic exiting when there are no resources to process isn't a "limitation". Besides, that occurs after you've had a chance to populate the resource collection, so why would it prevent you from populating the resource collection beforehand?
• Line 48: Why not just call empoweredProvider.LocateResourcesAsync() in the lambda instead of calling the private method (LocateStaticResourcesAsync) that calls it?

File: src/AspNetStaticContrib.Stekeblad/ResourceLocators/ActionDescriptor/ActionDescriptorQueryingMiddleware.cs

• Line 45: Requiring the remote/caller IP to be the loopback address may cause issues in some edge cases. Is this check really necessary? Isn't it enough to check that it's an AspNetStatic request?

File: Readme.md

• Line 27: "The built-in once..." s/b "The built-in ones..." -or- "The built-in resource locators...".
• Line 30: It's not clear what this is trying to convey. I think it's try to say... to use the built-in resource locators, call AddAspNetStaticContribStekeblad and enable the locators by setting the config options...?
• Line 140: Change to: "All ResourceLocatorBase implementations must perform the following tasks in LocateResourcesAsync:".

Happy New Year!

[Stekeblad]

IHostExtensions.cs

• Line 41: Your right! I'll fix. That was true in 0.26.2 when the check was made before registering on ApplicationStarted and I didn't notice that the check was moved into it.
• Line 48: At one point there was more logic in that method. I agree it's not needed anymore and will inline it

ActionDescriptorQueryingMiddleware.cs

• I just found a way to do this without using a custom endpoint or middleware. I will remove the middleware and related stuff and move the needed logic into ActionDescriptorPageResourceLocator. This also removes the need for checking for loopback or IsAspNetStaticRequest.

Readme.md

• Line 27: Corrected.
• Line 30: I have rewritten that point.
• Line 140: Your suggestion sounds better.

Happy New Year to you to!

[ZarehD]

Thank you for the contribution, @Stekeblad. Good work.