ContentId of Comments not set in OnAfterSave hook

[jensbrak]

A callback registered using Api.Hooks.Comments.RegisterOnAfterSave gets a Piranha.Models.Comment with the field ContentId set to all zeroes.

Steps to reproduce:

1. Install a fresh Razor template
2. Add the following line at bottom of Startup.cs:
   App.Hooks.Comments.RegisterOnAfterSave(c => Console.WriteLine(c.ContentId));
3. Run the template and submit a valid comment on any post

Output of application:

dotnet run
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: https://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://localhost:5000
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Development
info: Microsoft.Hosting.Lifetime[0]
      Content root path: C:\src\piranhatest
00000000-0000-0000-0000-000000000000

The same goes for comments posted with moderation turned on in manager, the first time the callback for OnAfterSave is called (user posted the comment). The second time the callback is called (admin approved comment) the field ContentId has a seemingly valid value.

[jensbrak]

Another observation: The hook for CommentValidation could use the ContentId of the comment to get information about the content the comment belongs to. However, here too the ContentId is zoroed, so there's no use for it in the Validation hook.

[jensbrak]

I have a PR fixing this. The ContentId is never assigned to the comment when the comment is added. The fix is to simply let the Page and Post services assign it, just as they ensure that date and comment id are valid. Perhaps the calling methods should do this (too or instead?) but it seems more logical to mr to have the services check for it and assign.

[tidyui]

It just looks like the repository is responsible for making the connection which is wrong. The ContentId of the comment should set here for posts (and in the same location for pages). https://github.com/PiranhaCMS/piranha.core/blob/master/core/Piranha/Services/PostService.cs#L623

[jensbrak]

Yes, exactly what I did. Works fine now. Just gonna do a PR för it as soon as I can.