Optimize PR CI with custom Docker image and pre-installed dependencies

Author: google-labs-jules[bot]

.ci/container/Dockerfile

@@ -0,0 +1,42 @@
+FROM ubuntu:24.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install common tools and dependencies
+RUN apt-get update && apt-get install -y \
+    curl \
+    wget \
+    unzip \
+    zip \
+    git \
+    python3 \
+    xvfb \
+    ant \
+    maven \
+    libncurses6 \
+    sudo \
+    openjdk-17-jdk \
+    openjdk-21-jdk \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Java 8 (Zulu FX)
+RUN mkdir -p /usr/lib/jvm
+# Using a specific version of Zulu 8 with FX
+RUN wget -q https://cdn.azul.com/zulu/bin/zulu8.82.0.21-ca-fx-jdk8.0.432-linux_x64.tar.gz -O /tmp/java8.tar.gz \
+    && tar -xzf /tmp/java8.tar.gz -C /usr/lib/jvm \
+    && mv /usr/lib/jvm/zulu8.82.0.21-ca-fx-jdk8.0.432-linux_x64 /usr/lib/jvm/java-8-zulu-fx \
+    && rm /tmp/java8.tar.gz
+
+# Download cn1-binaries
+# We download it to /opt/cn1-binaries so it can be reused
+RUN wget -q https://github.com/codenameone/cn1-binaries/archive/refs/heads/master.zip -O /tmp/cn1-binaries.zip \
+    && unzip -q /tmp/cn1-binaries.zip -d /opt \
+    && mv /opt/cn1-binaries-master /opt/cn1-binaries \
+    && rm /tmp/cn1-binaries.zip
+
+# Set convenient env vars
+ENV JAVA_HOME_8=/usr/lib/jvm/java-8-zulu-fx
+ENV JAVA_HOME_17=/usr/lib/jvm/java-17-openjdk-amd64
+ENV JAVA_HOME_21=/usr/lib/jvm/java-21-openjdk-amd64
+
+ENV CN1_BINARIES=/opt/cn1-binaries

.github/workflows/build-container.yml

@@ -0,0 +1,32 @@
+name: Build Container
+
+on:
+  push:
+    paths:
+      - '.ci/container/Dockerfile'
+      - '.github/workflows/build-container.yml'
+  workflow_dispatch:
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v4
+        with:
+          context: .ci/container
+          push: true
+          tags: ghcr.io/${{ github.repository }}/pr-ci-container:latest

.github/workflows/pr.yml

@@ -32,26 +32,36 @@ permissions:
   contents: write
   pull-requests: write
   issues: write
+  packages: read
 
 jobs:
   build-test:
 
     runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/${{ github.repository }}/pr-ci-container:latest
+      options: --privileged
     strategy:
       fail-fast: false
       matrix:
         java-version: [8, 17, 21, 25]
 
     steps:
     - uses: actions/checkout@v1
-    - name: Set up JDK 8
-      if: matrix.java-version == 8
-      uses: actions/setup-java@v1
-      with:
-        java-version: 1.8
-        java-package: jdk+fx
-    - name: Set up JDK
-      if: matrix.java-version != 8
+    - name: Configure Java
+      run: |
+        if [ "${{ matrix.java-version }}" == "8" ]; then
+          echo "JAVA_HOME=$JAVA_HOME_8" >> $GITHUB_ENV
+          echo "$JAVA_HOME_8/bin" >> $GITHUB_PATH
+        elif [ "${{ matrix.java-version }}" == "17" ]; then
+          echo "JAVA_HOME=$JAVA_HOME_17" >> $GITHUB_ENV
+          echo "$JAVA_HOME_17/bin" >> $GITHUB_PATH
+        elif [ "${{ matrix.java-version }}" == "21" ]; then
+          echo "JAVA_HOME=$JAVA_HOME_21" >> $GITHUB_ENV
+          echo "$JAVA_HOME_21/bin" >> $GITHUB_PATH
+        fi
+    - name: Set up JDK (Fallback/Java 25)
+      if: matrix.java-version == 25
       uses: actions/setup-java@v4
       with:
         distribution: 'zulu'
@@ -76,7 +86,12 @@ jobs:
       run: |
         set -euo pipefail
         rm -rf maven/target/cn1-binaries
-        git clone --depth=1 --filter=blob:none https://github.com/codenameone/cn1-binaries maven/target/cn1-binaries
+        mkdir -p maven/target
+        if [ -d "$CN1_BINARIES" ]; then
+           ln -s "$CN1_BINARIES" maven/target/cn1-binaries
+        else
+           git clone --depth=1 --filter=blob:none https://github.com/codenameone/cn1-binaries maven/target/cn1-binaries
+        fi
     - name: Run Maven plugin tests
       working-directory: maven
       env:
@@ -228,10 +243,15 @@ jobs:
           await publishQualityComment({ github, context, core });
     - name: Install dependencies
       run: |
-        sudo apt-get update && sudo apt-get install xvfb
-        wget https://github.com/codenameone/cn1-binaries/archive/refs/heads/master.zip
-        unzip master.zip -d ..
-        mv ../cn1-binaries-master ../cn1-binaries
+        if [ -d "$CN1_BINARIES" ]; then
+          echo "Using pre-installed cn1-binaries"
+          ln -s "$CN1_BINARIES" ../cn1-binaries
+        else
+          sudo apt-get update && sudo apt-get install xvfb
+          wget https://github.com/codenameone/cn1-binaries/archive/refs/heads/master.zip
+          unzip master.zip -d ..
+          mv ../cn1-binaries-master ../cn1-binaries
+        fi
     - name: Build CLDC11 JAR
       run: |
         ANT_OPTS_ARGS=""