Unreal Tournament '99 server
By
@DoMax
- 3 Devlogs
- 16 Total hours
An Unreal Tournament ’99 server - inside of a Docker container (with mod support through RedeeMOD)
Ship #1
Pending review
@DoMax
on
Unreal Tournament '99 server
Unreal Tournament 1999 server management made easy!
After playing around with UT99 for a while and mentioning it to a friend, he asked to play together. I encountered 2 problems though:
- On a VPS I didn’t want to install UT, as that could harm the rest of the architecture/provisioning (+ poor portability)
- Modding a server is difficult, requires manually editing the main config file
I decided that making a Docker container would be a great idea since UT99 has Linux-native executables.
While there already were attempts at making a Docker container of this game, they were mostly undermaintained and quite difficult to mod.
Development journey
I tried taking the easiest path of using Python scripts to provision the container on runtime, and to my surprise it worked!
At first I was simply launching the UT99 server binary with a generated config file from parsed environment variables, but in order to bring mod support I had to slightly modify my other project, RedeeMOD.
RedeeMOD didn’t have the capability to work as a CLI app (since in a server you don’t have a GUI to click). It uses Rich as a CLI backend and I made sure to leave no original functionality unimplemented.
Web admin panel comes by default, bundled with UT99, but it’s quite outdated, lacks functionality and may cause some segfaults on the server if used improperly. I didn’t block it on this container, but use at your own risk. Managing through plugins or in-game commands worked best for me.
Next came the automations, which were fairly easy to set up. CI/CD pipelines, pre-commit hooks and so on.
One thing I’m missing out on is tests, but since the Python source isn’t going to be anyhow built or changed, I didn’t feel a critical need for tests.
I did test it with unit tests locally, but didn’t include them within the git repo.
Can I check it out without spinning up Docker myself?
Yes! Server container is about 1GB in size (has to fit the whole game, unpacked) and downloading it would take time, so I spun up a free to use server at ut99.domax.lt
If you have an OldUnreal-patched version of Unreal Tournament, you can connect and play Deathmatch with your friends or bots! (Map voting is also added, both as a usability bonus and to demonstrate mods working)
@DoMax
on
Unreal Tournament '99 server
4h 55m 54s logged
Server is online!
You can connect to it by opening ut99.domax.lt on Unreal Tournament ’99 (has to be OldUnreal-patched)
What changed?
Very little. I added a README, and reorganized the environment variables.
I also implemented server setting replacement logic, which empties unset values if they have no defaults on startup.
This was done to leave no stale settings lingering inside of the .ini file.
What’s on the server?
It’s an only-deathmatch server with a plugin to vote for maps at the end of round, nothing more, so a pretty vanilla experience. Bots are tuned to be 6/8 difficulty, so you’ll have to practice a bit ;)
If something’s malfunctioning, reach out to me on Slack, and I’ll try to help fixing the problem.
@DoMax
on
Unreal Tournament '99 server
5h 58m 4s logged
MODS!
How I integrated mod support into the server (I’m very excited)
1. Why so many hours?
Adding mods would seem a fairly easy task, regarding that I had already built a mod launcher that supports CLI. Most of that time was spent debugging why the server image stopped immediately after starting.
RULE NUMBER 1: Learn from my mistakes, always check if your entrypoint process continues, or if it exits.
Turns out, my CLI app spawned a process… And exited! Which means that no matter what else was running, since the main container process no longer exists, the whole container shuts down.
The solution was to monitor the container’s SIGTERM/SIGINT signals that are handed upon stopping, and only THEN kill the RedeeMOD task. Otherwise, keeping it alive is necessary.
2. How did I actually add modding?
That was simple. I exchanged the executable from base UT99 server binary to RedeeMOD’s CLI and limited Python to disallow exiting early.
RedeeMOD handles everything natively, making me only supply the mod folders and nothing more.
The server runs, there’s just one annoying bug, but I believe it’s an issue in the executable itself. Using open {map_name} through server console instead of servertravel {map_name}?game=BotPack.{game_type} makes the whole server throw a segmentation fault and require a manual restart.
And the web admin panel is quite poor in terms of functionality. Some time in the future I might write an updated web panel and try to get a PR merged to OldUnreal’s upstream, but that’s not a priority for now.
Other than that, I’m feeling confident, and no more major overhauls await. Just the integration of GitHub actions for automated container builds, and some automation stuff (like pre-commit hooks).
@DoMax
on
Unreal Tournament '99 server
4h 40m 6s logged
New adventure of UT99 saga
After the success of RedeeMOD, my other project (a mod launcher for games), I decided I want to make an easier way of running dedicated Unreal Tournament ’99 servers.
The plan
My plan was to create a Docker container, mostly for portability. Since the server itself was already implemented by Epic Games back in 1999, all I have to do it to package it for Docker.
Thankfully, Epic back in the day supported Linux and included official binaries, which are still maintained by a volunteering group called OldUnreal. This meant I didn’t have to think about integrating Wine/Proton into the container!
And while a docker container for UT99 was previously made by someone, lack of updates disappointed me. I decided to make my own because of a couple reasons:
The technologies used
Having experience in UT99 modding, I decided to use Python since I could use RedeeMOD as a source for code templates.
Having coded a modding tool for this game was also trivial while asking AI - my own repos were heavily used as context.
In the near future I’m also planning to bake-in RedeeMOD for mod support for servers, providing great use of something I had already made!
Current stage
Today I have built a strong foundation for the server - it builds, validates and applies environment variables (through .ini patching) and runs the server with provided config. Within its run pipeline also has a place for near-future addition of modding.
Web panel works, LAN discovery too!
It has no CI/CD pipelines yet, but that’s one of the main things I’ll be taking a look at in the next day or so.
