Bulk banning and ban list subscriptions

[erkinalp]

Why is this needed

Ban lists would be quite useful in guilds that wish to share bans between them, due to shared ownership and/or ease of moderation. Bulk banning would be useful to quickly ban many users in defence of a raid.

The proposed features

This feature could be implemented in several ways:

• Ban lists as channels: In this alternative, a ban list would be a channel type and a guild would subscribe to a list by joining that channel. Reuses existing data structures. The disadvantage is ban reasons could not be reused in such a structure without making a backwards-incompatible change on ban entry representation.
• Bans get IDs: In this alternative, each ban would get a ban ID. You would import a ban by adding the ban by ID. To subscribe to a ban list as a whole, you would add the guild using that ban list. This alternative allows reusing the ban reasons. It also brings the possibility to edit the ban reasons after the fact.

Similarly, ban API would get a bulk ban endpoint, which would allow adding multiple users or ban lists at once, by user/ban list/guild ID.

Various concerns

Ban list adds should be implemented atomically, i.e. all ban adds in a given ban list change request should happen at once. This could be achieved by having a few seconds of artificial delay between the processing of the first item request and implementation of all items, if more than a certain number of ban entries are added at once.