migrate to custom RCON client

CHANGELOG.md

@@ -1,3 +1,7 @@
+## v0.2.0
+- Migrate to custom RCON client: https://gitea.jovan04.com/evan/WiRCON
+- Upgrade base image to Java 25
+
 ## v0.1.0
 - Initial release
 - Graceful shutdown via SIGTERM / SIGINT

Dockerfile

@@ -1,20 +1,24 @@
-# extract mcrcon
-FROM debian:bookworm-slim AS builder
-
-ADD https://github.com/Tiiffi/mcrcon/releases/download/v0.7.2/mcrcon-0.7.2-linux-x86-64-static.zip /usr/bin/mcrcon.zip
-RUN apt-get update && apt-get install -y unzip 
-
-RUN unzip -j /usr/bin/mcrcon.zip -d /usr/bin/mc-rcon && chmod a+x /usr/bin/mc-rcon/mcrcon
-
-
 # actual image
-FROM eclipse-temurin:21
+FROM eclipse-temurin:25
+
+RUN apt-get update 
+RUN apt-get install -y wget ca-certificates
+RUN apt-get install -y git
+RUN apt-get install -y python3
+RUN apt-get install -y build-essential
+
+RUN ln -s /usr/bin/python3 /usr/bin/python
+
+# build the RCON client
+RUN git clone https://gitea.jovan04.com/evan/WiRCON && cd WiRCON && make build && mv wircon.pyz /usr/bin/wircon.pyz && cp scripts/restart.py /usr/bin/restart.py
 
-COPY --from=builder /usr/bin/mc-rcon /usr/bin/mc-rcon
 COPY scripts/start-server.sh /usr/bin/start-server.sh
 RUN chmod a+x /usr/bin/start-server.sh
-COPY scripts/mcrcon /usr/bin/mcrcon
-RUN chmod a+x /usr/bin/mcrcon
+
+COPY scripts/rcon /usr/bin/rcon
+RUN chmod a+x /usr/bin/rcon
+
+# default minecraft server files
 COPY template/ /defaults/
 
 WORKDIR /minecraft_data

README.md

@@ -16,7 +16,7 @@ git clone https://gitea.jovan04.com/evan/minecraft-docker && cd minecraft-docker
 
 ### Build the Image
 ```sh
-docker build -t minecraft_server .
+docker build --pull -t minecraft_server .
 ```
 
 ### Run with Docker Compose
@@ -36,7 +36,29 @@ On first startup (when the data volume is empty):
 * 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.
+On subsequent startups, existing files are reused unchanged and environment variables are unused. To reset the server or create a new one, change the name in `volumes:  data:  name:  new_volume_name` in the `docker-compose.yml` file. 
+
+### Upgrading Java Version
+Occasionally, Minecraft will update the Java version they compile their class files with. Because the Java runtime is pre-bundled with the Docker container, an update from Minecraft requires an update and rebuild of the Docker container. 
+
+You can tell this is required if there are errors like the following when trying to start the server:
+```
+minecraft_server  | Error: LinkageError occurred while loading main class net.minecraft.bundler.Main
+minecraft_server  | 	java.lang.UnsupportedClassVersionError: net/minecraft/bundler/Main has been compiled by a more recent version of the Java Runtime (class file version 69.0), this version of the Java Runtime only recognizes class file versions up to 65.0
+minecraft_server exited with code 1 (restarting)
+```
+
+To upgrade, change the base eclipse-temurin image's version to one supported by the latest Minecraft version. In `./Dockerfile`:
+```
+# previously, eclipse-temurin:21
+FROM eclipse-temurin:25
+```
+
+Then, rebuild the container and start as normal:
+```sh
+docker build --pull -t minecraft_server .
+docker compose up -d
+```
 
 ### 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 only. **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.
@@ -45,19 +67,18 @@ 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`. 
+Use the provided wrapper script (located at `/usr/bin/rcon`). The script dynamically reads the password from `/minecraft_data/server.properties`. 
 
 Send a single command: 
 ```sh
-mcrcon list
-mcrcon stop
+rcon -e list
 ```
 
-For an interactive console (`Ctrl-C` or `Ctrl-D` to quit):
+For an interactive console (`Ctrl-D` to quit):
 ```sh
-mcrcon
+rcon
 ```
-Use this the same as typing into the actual server console
+Use this the same as typing into the actual server console.
 
 ### Graceful Shutdown Behavior
 When the container receives SIGTERM or SIGINT:

scripts/rcon

@@ -1,4 +1,4 @@
 #!/bin/bash
-exec /usr/bin/mc-rcon/mcrcon -p "$(
+exec /usr/bin/wircon.pyz -H localhost -p "$(
   grep '^rcon.password=' /minecraft_data/server.properties | cut -d= -f2-
 )" "$@"

scripts/start-server.sh

@@ -7,7 +7,7 @@ if ! test -f /minecraft_data/server.jar; then
         echo "ERROR: SERVER_JAR_DOWNLOAD_URL not set for initial volume creation"
         exit 1
     fi
-    wget -O /minecraft_data/server.jar "${SERVER_JAR_DOWNLOAD_URL}"
+    wget --no-verbose -O /minecraft_data/server.jar "${SERVER_JAR_DOWNLOAD_URL}"
 fi
 
 # server.properties
@@ -24,12 +24,13 @@ if ! test -f /minecraft_data/eula.txt; then
     cp /defaults/eula.txt /minecraft_data/eula.txt
 fi
 
+
 export MCRCON_PASS=$(grep "^rcon.password=" /minecraft_data/server.properties | cut -d '=' -f 2- | head -n 1)
 
 # shutdown process
 function shutdown {
     echo "stopping Minecraft server..."
-    /usr/bin/mc-rcon/mcrcon -p ${MCRCON_PASS} -w 5 "say Server is restarting!" save-all stop
+    /usr/bin/wircon.pyz -H localhost -p ${MCRCON_PASS} -E /usr/bin/restart.py
     wait $SERVER_PID
 }