Restore the GraalVM image variants

.github/workflows/build.yml

@@ -30,10 +30,13 @@ jobs:
           - java25
           - java25-alpine
           - java25-jdk
+          - java25-graalvm
           - java21
           - java21-alpine
+          - java21-graalvm
           - java21-jdk
           - java17
+          - java17-graalvm
           - java16
           - java11
           - java8
@@ -54,6 +57,10 @@ jobs:
             baseImage: eclipse-temurin:25
             platforms: linux/amd64,linux/arm64
             mcVersion: latest
+          - variant: java25-graalvm
+            baseImage: container-registry.oracle.com/graalvm/jdk:25-ol10
+            platforms: linux/amd64,linux/arm64
+            mcVersion: latest
         # JAVA 21:
           - variant: java21
             baseImage: eclipse-temurin:21-jre
@@ -67,12 +74,20 @@ jobs:
             baseImage: eclipse-temurin:21-jre-alpine
             platforms: linux/amd64,linux/arm64
             mcVersion: 1.21.11
+          - variant: java21-graalvm
+            baseImage: container-registry.oracle.com/graalvm/jdk:21-ol10
+            platforms: linux/amd64,linux/arm64
+            mcVersion: 1.21.11
         # JAVA 17:
           - variant: java17
             # jammy doesn't work until minecraft updates to https://github.com/netty/netty/issues/12343
             baseImage: eclipse-temurin:17-jre-focal
             platforms: linux/amd64,linux/arm/v7,linux/arm64
             mcVersion: 1.20.4
+          - variant: java17-graalvm
+            baseImage: container-registry.oracle.com/graalvm/jdk:17-ol10
+            platforms: linux/amd64,linux/arm64
+            mcVersion: 1.20.4
         # JAVA 16
           - variant: java16
             baseImage: adoptopenjdk:16-jre-hotspot

.github/workflows/verify-pr.yml

@@ -24,6 +24,7 @@ jobs:
         variant:
           - java25
           - java25-alpine
+          - java25-graalvm
           - java17
           - java8
         include:
@@ -39,6 +40,11 @@ jobs:
             mcVersion: latest
             # For GLIBC_2.34 support (and Alpine)
             knockdRepoOrg: Metalcape/knock
+          - variant: java25-graalvm
+            # stay aligned with build.yml
+            baseImage: container-registry.oracle.com/graalvm/jdk:25-ol10
+            platforms: linux/amd64,linux/arm64
+            mcVersion: latest
         # JAVA 17:
           - variant: java17
             # jammy doesn't work until minecraft updates to https://github.com/netty/netty/issues/12343
@@ -69,6 +75,9 @@ jobs:
       - name: Setup Docker Buildx
         uses: docker/setup-buildx-action@v4
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v4.2.0
+
       - name: Confirm multi-arch build
         uses: docker/build-push-action@v7
         with:

build/ol/install-packages.sh

@@ -66,16 +66,12 @@ fi
 # Clean up DNF when done
 dnf clean all
 
-cat <<EOF > /usr/local/sbin/knockd
-#!/bin/sh
-
-echo "Auto-pause (using knockd) is currently unavailable on graalvm image variants"
-echo "Consider using a different image variant https://docker-minecraft-server.readthedocs.io/en/latest/versions/java/"
-echo "or mc-router's auto scale up/down feature https://github.com/itzg/mc-router#docker-auto-scale-updown"
-exit 2
-EOF
-chmod 755 /usr/local/sbin/knockd
-# TODO restore retrieval from https://github.com/Metalcape/knock when tar's "Cannot open: Invalid argument" is solved
+# Download and install patched knockd
+curl -fsSL -o /tmp/knock.tar.gz https://github.com/Metalcape/knock/releases/download/0.8.1/knock-0.8.1-$TARGET.tar.gz
+tar -xf /tmp/knock.tar.gz -C /usr/local/ && rm /tmp/knock.tar.gz
+ln -s /usr/local/sbin/knockd /usr/sbin/knockd
+ls -l /usr/local/sbin/knockd
+setcap cap_net_raw=ep /usr/local/sbin/knockd
 
 # Set git credentials globally
 cat <<EOF >> /etc/gitconfig

build/ol/setup-user.sh

@@ -1,2 +1,6 @@
+#!/bin/sh
+
+set -e
+
 groupadd --gid 1000 minecraft
 useradd --system --shell /bin/false --uid 1000 -g minecraft --home /data minecraft

docs/versions/java.md

@@ -17,17 +17,22 @@ where `<tag>` refers to the first column of this table:
 | java25        | 25           | Ubuntu | Hotspot     | amd64, arm64, riscv64 |      |
 | java25-alpine | 25           | Alpine | Hotspot     | amd64, arm64          |      |
 | java25-jdk    | 25           | Ubuntu | Hotspot+JDK | amd64, arm64          |      |
+| java25-graalvm | 25          | Oracle | Oracle GraalVM | amd64, arm64       | (2)(3) |
 | java21        | 21           | Ubuntu | Hotspot     | amd64, arm64          |      |
 | java21-jdk    | 21           | Ubuntu | Hotspot+JDK | amd64, arm64          |      |
 | java21-alpine | 21           | Alpine | Hotspot     | amd64, arm64          |      |
+| java21-graalvm | 21          | Oracle | Oracle GraalVM | amd64, arm64       | (2)(3) |
 | java17        | 17           | Ubuntu | Hotspot     | amd64, arm64, armv7   |      |
+| java17-graalvm | 17          | Oracle | Oracle GraalVM | amd64, arm64       | (2)(3) |
 | java16        | 16           | Ubuntu | Hotspot     | amd64, arm64, armv7   | (1)  |
 | java11        | 11           | Ubuntu | Hotspot     | amd64, arm64, armv7   |      |
 | java8         | 8            | Ubuntu | Hotspot     | amd64, arm64, armv7   |      |
 
 Notes
 
 1. This version of Java is [recommended for PaperMC 1.16.5](https://docs.papermc.io/paper/getting-started/#requirements)
+2. Based on the [Oracle GraalVM images](https://blogs.oracle.com/java/post/new-oracle-graalvm-container-images), which as of JDK 17, are now under the [GraalVM Free License](https://blogs.oracle.com/java/post/graalvm-free-license) incorporating what used to be known as the GraalVM Enterprise.
+3. Due to these images using Oracle Linux, (which is based on Red Hat Enterprise Linux) Forge Installer will not work due to its use of zlib-ng. Use other images for initial installation and Forge version upgrade.
 
 !!! example "Example using java8"
 
@@ -121,7 +126,6 @@ Forge also doesn't support openj9 JVM implementation.
 
 The following image tags have been deprecated and are no longer receiving updates:
 
-- java25-graalvm, java21-graalvm, java17-graalvm
 - adopt13
 - adopt14
 - adopt15