add Dockerfile, docker-compose, dependencies, and documentation

README.md

@@ -0,0 +1,69 @@
+# Minecraft Docker Server
+A docker image and compose build for running and controlling a Minecraft server from inside a Docker container. 
+* Supports any version of Minecraft; you just need a link to the server.jar
+    * tested on 1.21, more to come
+* Server console access via [RCON](https://minecraft.wiki/w/RCON)
+    * uses [Tiiffi/mcrcon](https://github.com/Tiiffi/mcrcon) as a prepackaged RCON client
+* All server files stored in a Docker volume
+* Graceful shutdown handling (SIGTERM / SIGINT)
+
+## Usage
+Requires [Docker](https://docs.docker.com/engine/install/), [Git](https://git-scm.com/install/), and a clone of this repository:
+```sh
+git clone https://gitea.jovan04.com/evan/minecraft-docker && cd minecraft-docker
+```
+
+### Build the Image
+```sh
+docker build -t minecraft_server .
+```
+
+### Run with Docker Compose
+`docker-compose.yml` (included in this repository):
+```sh
+docker compose up -d
+```
+(or `docker-compose` for older versions of Docker Compose)
+
+### First Startup
+On first startup (when the data volume is empty):
+* `server.properties` is created from a template
+* `eula.txt` is generated and automatically accepted
+* A default RCON configuration is written
+* `server.jar` is downloaded from a provided link
+
+On subsequent startups, existing files are reused unchanged and environment variables are unused.
+
+### RCON Access
+Minecraft implements the Remote Console (RCON) protocol, which allows server administrators to remotely execute commands. See more info [here](https://minecraft.wiki/w/RCON) and [here](https://developer.valvesoftware.com/wiki/Source_RCON_Protocol). RCON access is enabled automatically from inside the container. **Do not expose the RCON service to the internet directly!!!** RCON is not encrypted, so exposing this service can give hackers direct access to your server's administrator console.
+
+Log into the container:
+```sh
+docker exec -it minecraft_server bash
+```
+Use the provided wrapper script (located at `/usr/bin/mcrcon`). The script dynamically reads the password from `/minecraft_data/server.properties`. 
+
+Send a single command: 
+```sh
+mcrcon list
+mcrcon stop
+```
+
+For an interactive console (`Ctrl-C` or `Ctrl-D` to quit):
+```sh
+mcrcon
+```
+Use this the same as typing into the actual server console
+
+### Graceful Shutdown Behavior
+When the container receives SIGTERM or SIGINT:
+1. A 10-second warning message is broadcast to the server
+2. All chunks are saved manually
+3. A `stop` command is sent to the Minecraft server
+4. The server shuts down normally
+5. The container waits up to a configurable timeout before force-exiting, in case large worlds take a long time to save or the server hangs
+    * default 120s; configure this by changing the `stop_grace_period` time in `docker-compose.yml`
+
+### Configuration
+All Minecraft configuration is done through `server.properties`. Make any necessary changes before **building the image** to the file in this repository, or manually edit the `server.properties` file in the Minecraft server's Docker volume. More info about Docker volumes can be found [here](https://docs.docker.com/engine/storage/volumes). This container should work fine with a relative path in `docker-compose.yml` instead of a named volume. 
+