Delete chat messages

[jakobroehrl]

Fix #774

Todo

• Delete message content from database
• Add a system message so the old one can be deleted/updated in stores (web ui and mobile clients)
• Currently limited to 6h old messages
• Show a warning if matterbridge is active
• Write integration tests
• Add capability
• Adjust documentation
• change delete possibility: Only my messages within 6 hours after sending can be deleted

[sudwhiwdh]

How will users learn what this feature/action means in a uncomplicated way, i.e. without reading any documentation before?
For example, in terms of the available time window of 15 minutes or how to deal with federated messages.

[jakobroehrl]

How will users learn what this feature/action means in a uncomplicated way, i.e. without reading any documentation before?
For example, in terms of the available time window of 15 minutes

Only give the option when it's possible.

or how to deal with federated messages.

Hmm, do you have an idea. If that is a problem let's close this PR.

[sudwhiwdh]

How will users learn what this feature/action means in a uncomplicated way, i.e. without reading any documentation before?
For example, in terms of the available time window of 15 minutes

Only give the option when it's possible.

However, this still does not explain to users in which time window they can/should react with the Delete action, does it?

or how to deal with federated messages.

Hmm, do you have an idea. If that is a problem let's close this PR.

I don't know if that's a problem. What problems do you see in this case?

For me, it's definitely a matter of transparent communication so that there are no false expectations. It would be simply important for me that users understand in a comprehensible way from which server or device the message can be deleted with this action and for which people the message will still be visible after deletion.

Btw. is it technically possible to retrieve a message from a federated Nextcloud server within fifteen minutes?

[nickvergessen]

So multiple things with this:

1. Deleting gives a wrong impression when "Matterbridge" is configured for this channel, as the message is synced already to other chats where we can no longer delete the message. From my personal POV we should either show a warning on deleting that the message was federated and always will be "public" information, or not allow deleting in matterbridged conversations at all.
2. Since the last message id of a conversation is set and the messages are downloaded by our mobile clients, deleting from the DB is not a good idea and doesn't help a lot. Instead we should only wipe the content of the message (if the database structure allows it to be empty) and at the same time we need to add a "hidden" message that the message with ID X was deleted, so the clients can remove the message from their local store as well.
3. Regarding time restriction, we checked a bit what others do and they are a bit more "lax", Whatsapp 1 hour, Signal 3 hours, Line IM 24 hours, Telegram infinite. So we would go with 6 hours for now.

I can help with the backend if you want.

[nickvergessen]

Converting to draft for backend work

[jakobroehrl]

@nickvergessen Please ping me if you are ready with the backend work, I can test this, if you want.

[nickvergessen]

Should be ready to play around with it, integration tests are still missing, same for capability and documentation

[jakobroehrl]

I can delete, but after the page reload the deleted messaage is visible again

[nickvergessen]

I forcepushed because of a rebase. make sure your pulling worked

[jakobroehrl]

It's working super nice!

[nickvergessen]

Screenshots

Moderator	User

[nickvergessen]

Ah, conflict from #5019
Rebased

[PVince81]

All green! Merge for 21 or hold until the 22 split ?

[nickvergessen]

/backport to stable21.1

[kinimodmeyer]

Note: in a one-to-one chat both users are in fact moderators

can we not change the condition to allow this only for moderator in group chats?
sounds not 100% right when i write a important message to a employe and he can just delete them if he wants.
in group chats ppl understand that there is a "moderator/admin" who could do this.

[PVince81]

@kinimodmeyer please feel free to raise a new ticket for this request

[theoneandonly-vector]

"Currently limited to 6h old messages" is there a way to change this?

[marcoambrosini]

@nickvergessen @jancborchardt should this be tweakable in the admin settings?

[nickvergessen]

No