It seems we have a double spend problem with likes on Nostr...
I was able to like my own note 3 times. (Did it with nostrgram)
Discussion
That's weird. I usually get an error in #nostrgram when trying to relike a note. Says that I've already liked it
Most of the time it gives such a notification indeed. But sometimes it glitches. Especially if you hit the like button fast.
We’re not good at it today, however there ate at least a dozen common anti-pattern events that should be filtered by relays.
One example is does an existing reaction event exist from this pubkey for this event.
Events with multiple root etags.
Reactions with multiple p-tags.
Metadata events that are not JSON.
Others include DMs with multiple p-tags, as only one person can read - however maybe DMs mentions someone. Either way you leak data.
I have a list somewhere.