An extension depending on other extensions

squeevee

I recognize that making an extension depend on another extension goes hard against the spirit of modular design, but I'm convinced it's unavoidable in my case. Likes, tags, following, and mentions are indispensable features of social media and they are implemented as extensions, not Core features. My extension needs to depend on those extensions in order to marshal that information to ActivityPub.

Since extensions are Composer packages, and Core (quite generously) exposes the ExtensionManager class, this strikes me as a manageable (if uffish) quirk of my use case (rather than a horrible heap of smells and gotchas, see: WordPress plugins that depend on other WordPress plugins.) Maybe I'm making a bigger deal out of it than it needs to be, but for a project quite as ambitious as what I'm proposing I think some seriousness about design is warranted.

Is this kind of thing precedented on Flarum? Does anyone have particular advice or a recommended approach?

jordanjay29

It's a little precedented. There's a few extensions that rely on others, the most notable probably being Flagrow Bazaar. The link is to its composer.json file, which showcases how it requires other extensions (in particular, flagrow/console).

Quite honestly, if you wanted to, you could distribute an extension that was nothing more than a composer.json file meant to install a whole library of extensions. No one has done it yet, likely because extensions like Bazaar exist for easy extension management and discovery, but you could use this or Bazaar's composer method to install dependencies that just happen to be other extensions.

luceos

jordanjay29 note that flagrow/console is actually meant as a library - not an extension - to be used by extensions, nevertheless the same applies. One of my extensions that isn't out yet (the kanban one called Aqueduct) actually needs tags for it to work, therefore masquerade has a "require" set so that it depends on the extension to be downloaded as well.