Does anyone have a creative way to get a file's internal ID from its path? I'm limited to getting it client side.

With suiteQL, something like the below should work. Its a little hacky and will be slow. You could probably do something similar with search but I'm not sure the performance would be any better.

select
  f.id,
  f.name,
  fo.appfolder,
  replace(fo.appfolder,' : ','/')||'/'||f.name as path
from
  File f
  join MediaItemFolder fo on fo.id = f.folder
where
  replace(fo.appfolder,' : ','/')||'/'||f.name=<PATH TO LOOKUP>

That's amazing. Thank you very much

You could probably also make a suitelet which uses the file module to look up the Id and then call it from the client.

Yes, I know how to do that, but this has to work client side only with no server side code at all.