Afform - Dispatch event to alter admin metadata; provide mixin

[colemanw]

Overview

Makes Form-Builder more extensible by allowing extensions to add to the list of available entities, elements, input types, styles, etc.

Before

Entities were gathered only by file-scanning. Other metadata like elements & styles not alterable.

After

Instead of scanning files for Afform entities, this dispatches an event to allow metadata be altered.
It provides a mixin which extensions can use to automatically do the file scanning for entities, similar to the scanning for Ang modules and managed entities.

Technical Details

Extensions which rely on file scanning should subscribe to the mixin and also add a small shim for backward-compatibility.
Like this.

[civibot]

(Standard links)

• If this is your first pull-request for CiviCRM, please browse CONTRIBUTING.md for information about the development and testing processes.
• If you are reviewing this pull-request, you may wish to consult the test sites and the Review Standards (long template, short template).

[colemanw]

ping @MegaphoneJon in case you are creating Afform entities.

[MegaphoneJon]

I wasn't but now I might! :)

[jaapjansma]

I have tested this with the config items extensions and the form builder and to me it looks like it works.

[MegaphoneJon]

@jaapjansma @colemanw Could one of you please post some sample code here? Full updating of docs.civicrm.org is best, but I think at this point, documenting events is probably going to require a more concerted effort.

[seamuslee001]

This seems to make sense but I agree with Jon that we need some dev docs on this

[colemanw]

OK I've added dev docs here: https://lab.civicrm.org/documentation/docs/dev/-/merge_requests/996