Kicking off the discussion on modular exports here.
We need:
An action for the export page to run dependency checks for external modules.
A filter for the export page to add external modules to the list of export formats (to discuss: how do we determine where do they fit into the existing lists?).
A filter for the export class to add selected external module(s) to the export routine.
Related to this, modules that require their own export assets will need their own themes that contain these assets. So we should probably use theme_support to determine whether a theme supports an export format (so, for example, only Luther supports mPDF; it should be disabled for Clarke, Fitzgerald, etc). Thoughts, all?
That seems like a good approach. The other idea I had in mind was filtering a multilevel array of the two existing columns, so that you could (for example) create a module that gets inserted between PDF and EPUB in the existing structure. A little more complex but maybe more flexible in the long run?
Oh, I think like that better @ned. Doesn’t seem too much more complex to make that work, and if it makes it more flexible in the long run, it would make sense to implement it in that way. Keeps the ui a little cleaner too.