How do I add arbitrary metadata to a .dae export? I am assuming that a basic python script can be written to achieve this. I am trying to add some information packed into my exported .dae that will include an UUID for use in an external application. My best guess right now is that I can use an "extra" tag somehow, like Blender uses for importing/exporting scene lights set up in Blender. I am going to be using this repeatedly for many exported files.
Thanks for any help you can provide! Let me know if you need more info!
The collada support built into blender is done using C++ code. I would suggest getting this collada-exporter addon and adjusting it to add in your extra data. You will need to look through the collada specs to see how an extra tag would be acceptable within the file format.

Unless you calculate the tag as you go, you can add a custom property to the object type to store the tag info, then use that in the export steps. You would define that in the addons register()

def register():
    bpy.types.Object.mytag = bpy.props.StringProperty()