Error when a Matrix message is empty

[erebion]

When a Matrix message contains an empty body, the bridge responds with an error:

⚠ Your message was not bridged: 50006: Cannot send an empty message

This is annoying, as this allows spamming a room quite easily.

10 empty messages become 20 messages as 10 error messages are added.

Logs contain the following:

2025-05-19T17:06:48Z DBG Sent message checkpoint message_checkpoint={"event_id":"$Ev9YPSJ4HVnj08uhJs5RN3PsF3PV4-BLmljY-IAEK50","event_type":"m.room.message","message_type":"m.text","reported_by":"BRIDGE","retry_num":0,"room_id":"!avHtPbJBFIkqXODJcI:matrix.un-hack-bar.de","status":"SUCCESS","step":"BRIDGE","timestamp":1747674408484}
2025-05-19T17:06:48Z ERR Matrix event not handled error="HTTP 400 Bad Request, {\"message\": \"Cannot send an empty message\", \"code\": 50006}" action="send matrix message metrics" channel_id=637233944919539712 channel_receiver= event_id=$Ev9YPSJ4HVnj08uhJs5RN3PsF3PV4-BLmljY-IAEK50 event_type=m.room.message result="Error sending event" room_id=!avHtPbJBFIkqXODJcI:matrix.un-hack-bar.de sender=@erebion:ejabberd.erebion.eu
2025-05-19T17:06:48Z DBG Sent message checkpoint message_checkpoint={"event_id":"$Ev9YPSJ4HVnj08uhJs5RN3PsF3PV4-BLmljY-IAEK50","event_type":"m.room.message","info":"HTTP 400: 50006: Cannot send an empty message","message_type":"m.text","reported_by":"BRIDGE","retry_num":0,"room_id":"!avHtPbJBFIkqXODJcI:matrix.un-hack-bar.de","status":"PERM_FAILURE","step":"REMOTE","timestamp":1747674408637}

The bridge should just ignore empty messages or at least have a setting that allows ignoring them, without disabling all error messages.

EDIT: fixed a typo
EDIT 2: fixed another typo

[Neustradamus]

@erebion: Thanks for your ticket :)

[erebion]

@erebion: Thanks for your ticket :)

I hope it will have an effect. And I would fix this myself, but nor sure how.

Anyway, I'm not sure why this would even be an error.

There's nothing to bridge. Why would there be an error?