You just need to the broadcast notes to them
Discussion
Okay so if I understand correctly, I should set up my own relay with my users' notes. Those notes contain the image URLs only (actual image data will be stored by me), and then my relay should broadcast these notes to other relays, who will automatically pick them up?
You could broadcast the notes to your relay and other relays all at the same time. That’s how it’s normally done. Running your own relay is to ensure the note gets stored cause other relays can reject your notes if they want.
I don’t know if this works but might be the easiest way to add sharing functionality: https://github.com/coracle-social/nub
Doesn’t seem to work :(
If you’re going to store the media, I suggest reading nip-96 or check out Blossom.