Better whitelist and ops support in offline mode

[FedotCompot]

Enhancement Type

Improve an existing feature

Describe the enhancement

When online-mode=false OPS and WHITELIST users that are not found using playerdb.co should have UUIDs generated offline using something like this.

If necessary i can provide js and bash scripts that generate offline UUID from a nickname, it's some basic bit manipulation of the md5 hash of the nickname

[itzg]

Thanks for the suggestion and advice about deriving from the md5. That'll be quite feasible to add here

https://github.com/itzg/mc-image-helper/blob/master/src/main/java/me/itzg/helpers/users/ManageUsersCommand.java

[FedotCompot]

Created a PR with implementation and test itzg/mc-image-helper#581

[itzg]

Can now bump the version in Dockerfile to pickup

https://github.com/itzg/mc-image-helper/releases/tag/1.44.0

[FedotCompot]

itzg/mc-image-helper#581 is a temp solution in my opinion, it's a quickie that allows the server to start with offline players in the white/op list.

But it does not handle properly mixed user, the solution to this in my opinion would be to use per-user flag to mark them as offline

---

My proposal is to use some kind of delimiter that is not be allowed in a nickname to inject flags directly into the username/uuid
Something like this:

• user:offline,flag1
• user:offline:flag1
• user<offline,flag2>
• user<offline><flag2>
• user#offline,flag3
• user#offline#flag3
• uuid-uuid-uuid-uuid/offline,flag4
• uuid-uuid-uuid-uuid/offline/flag4

So something like this is possible:

[username, flags] = entry.split(FLAG_DELIM)
...
for flag in flags.split(",") {
   switch flag {
    ...
    case FLAG_OFFLINE:
      return generateOfflineUUID(username)
  }
}

This wound not only allow for offline usernames tagging, but also enables an easy way to implement other per-user functionality.

Also this would not even be a breaking change since a normal nickname entry would just have no tags

[itzg]

Your new suggestion makes sense -- colon delimiter is what I'd prefer. How about you open a follow up enhancement issue for this new idea?

But I'm confused, did you not even want to use the "temp solution"? Why did you request I review a temp solution without telling me? To clarify, you have to make changes here in the image to at least pull in that version of the helper.

docker-minecraft-server/Dockerfile

Line 51 in 1cf2783

ARG MC_HELPER_VERSION=1.43.1

[FedotCompot]

At first i thought this was a good solution, but after i did the PR i set up another server for a group of friends and there were both online and offline players, then i realized having either all offline or all online is not enough.

P.S.
I just got a couple of weeks ago in hosing mc server on docker, previously i was doing everything by hand using crontab and screen, when i found out about your repos and helm charts i was amazed. And seeing all of this being basically maintained by one person made me want to contribute, but since I'm really new to all of this I may not see all of the use cases, possibilities and potential issues.

[itzg]

Ah ok, that's totally fair then. Thanks for clarifying the context.

I'm good if you want to proceed with the follow up PR in image helper to allow for mixed online/offline.

I really appreciate the help you're providing on these features.