Listing available Custom Resource Classes?

Is there a way to know which resource classes are available? One solution is to do a "SELECT DISTINCT" type of query on the modx_site_content table, but I'm hoping for a solution that shows which classes are available even BEFORE any content has been created.

Thanks!

Maybe you could grep the class files in core/component with a regex something like '/extends.*modResource.*$/' or do it with the DirWalker class in a snippet.

The class key dropdown on the resource settings tab I believe talks to the system/derivatives/getlist processor, maybe you can piggyback of that with $modx->runProcessor. Or look at its source for inspiration, apparently there's a $modx->getDescendants method that will look at $modx->classMap to find out what's available.

For the record, I'm now somewhat opposed to creating new class_keys if the custom resource is meant mainly to be used instead of the original. I think it's cleaner in most such cases to extend the original object without modifying the class_key. ClassExtender has been modified to leave the class_key fields alone for both modResource and modUser.

Of course if you need to query just those custom objects (especially if you have a lot of them), changing the class_key makes more sense.

Huh, how can you extend it without creating a new class?

My understanding of the architecture here is that it follows a single-table-inheritance pattern, so everything in there is a resource, but the class_key defines which class is implementing/extending the base interface/class.

I suspect the processors must contain the solution somewhere... how else does the right-click menu know which options are available, including CRCs?

Quote from: Everettg_99 at Nov 14, 2014, 06:30 AM

My understanding of the architecture here is that it follows a single-table-inheritance pattern, so everything in there is a resource, but the class_key defines which class is implementing/extending the base interface/class.

I suspect the processors must contain the solution somewhere... how else does the right-click menu know which options are available, including CRCs?

It traverses the classMap (which is created when building the model from the schema) for descendants.

Quote from: markh at Nov 14, 2014, 06:21 AM

Huh, how can you extend it without creating a new class?

You create a custom table for the extra fields, then make modResource a related object of the custom object (which extends modResource). The class_key is still modDocument.



You can no longer do this:



You can, however, do fast queries on the custom table and use getObjectGraph() on it to query it in combination with the resource fields.



Or for users, get the user, the custom data, and the profile all at once:



This way, the custom class will work with multiple other custom classes that extend the same object (like Articles), which wouldn't allow you to do $article->getOne('Data').

Right, so you are not actually extending the resource/user there, but just creating a separate table to store stuff. And creating a relation back to the resource for convenience. If you just want to store extra data (without using the resource properties) that makes complete sense.

Anyone know the ins/outs of the modx_class_map table? That seems to look promising, but it does not appear to be populated by any Extras, only used by the core (?). It looks like this table would accomplish *exactly* what I'm hoping for: an accessible way to "register" classes so that add-ons can be aware of them.