In my Node.js code with superagent, the privilege should've been groups:posts:downvote rather than group:posts:downvote. I got privileges manipulation to work now!
This is a sad song, I forgot to backup the avatars and pictures uploaded by the user.
So I loss them all, and now them will be 404 when openning my site.
I only know about deleting fields of 404 in the database, but this workload is too much.
Who can tell me how to delete resources of 404 efficiently, thanks a lot.