Add multi-architecture image build (#314)

Author: itzg

.github/workflows/ci.yml

@@ -19,20 +19,12 @@ jobs:
     if: github.repository == 'itzg/docker-minecraft-bedrock-server'
 
     steps:
-      - name: Checkout
-        uses: actions/checkout@v3
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v2
 
-      - name: Cache Docker layers
-        uses: actions/cache@v3
-        with:
-          path: /tmp/.buildx-cache
-          key: ${{ runner.os }}-buildx-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-buildx-
-
       - name: Login to DockerHub
         if: github.event_name != 'pull_request'
         uses: docker/login-action@v2
@@ -42,17 +34,18 @@ jobs:
 
       - name: Docker Metadata action
         id: meta
-        uses: docker/metadata-action@v4.3.0
+        uses: docker/metadata-action@v4
         with:
           images: itzg/minecraft-bedrock-server
           flavor: |
-            latest=${{ github.event_name == 'push' && github.ref == 'refs/heads/master' }}
+            latest=${{ github.event_name == 'push' && github.ref_name == 'master' }}
 
       - name: Build and push
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@v4
         with:
-          context: .
           push: ${{ github.event_name != 'pull_request' }}
+          provenance: false
+          platforms: linux/amd64,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}
           labels: |
             ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -1,9 +1,8 @@
 FROM debian
 
-# ARCH is only set to avoid repetition in Dockerfile, use --build-arg ARCH=arm64 for arm cpu
-ARG ARCH=amd64
-
-ARG APT_UPDATE=20210112
+# hook into docker BuildKit --platform support
+# see https://docs.docker.com/engine/reference/builder/#automatic-platform-args-in-the-global-scope
+ARG TARGETARCH
 
 RUN apt-get update && \
   DEBIAN_FRONTEND=noninteractive apt-get install -y \
@@ -14,7 +13,7 @@ RUN apt-get update && \
     && rm -rf /var/lib/apt/lists/*
 
 # Instal box64 on arm
-RUN if [ "$ARCH" = "arm64" ] ; then \
+RUN if [ "$TARGETARCH" = "arm64" ] ; then \
     apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y debian-keyring && \
     curl -L https://ryanfortner.github.io/box64-debs/box64.list -o /etc/apt/sources.list.d/box64.list && \
@@ -34,16 +33,16 @@ WORKDIR /data
 ENTRYPOINT ["/usr/local/bin/entrypoint-demoter", "--match", "/data", "--debug", "--stdin-on-term", "stop", "/opt/bedrock-entry.sh"]
 
 ARG EASY_ADD_VERSION=0.7.0
-ADD https://github.com/itzg/easy-add/releases/download/${EASY_ADD_VERSION}/easy-add_linux_${ARCH} /usr/local/bin/easy-add
+ADD https://github.com/itzg/easy-add/releases/download/${EASY_ADD_VERSION}/easy-add_linux_${TARGETARCH} /usr/local/bin/easy-add
 RUN chmod +x /usr/local/bin/easy-add
 
-RUN easy-add --var version=0.4.0 --var app=entrypoint-demoter --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/v{{.version}}/{{.app}}_{{.version}}_linux_${ARCH}.tar.gz
+RUN easy-add --var version=0.4.0 --var app=entrypoint-demoter --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/v{{.version}}/{{.app}}_{{.version}}_linux_${TARGETARCH}.tar.gz
 
-RUN easy-add --var version=0.1.1 --var app=set-property --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${ARCH}.tar.gz
+RUN easy-add --var version=0.1.1 --var app=set-property --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${TARGETARCH}.tar.gz
 
-RUN easy-add --var version=1.6.1 --var app=restify --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${ARCH}.tar.gz
+RUN easy-add --var version=1.6.1 --var app=restify --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${TARGETARCH}.tar.gz
 
-RUN easy-add --var version=0.5.0 --var app=mc-monitor --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${ARCH}.tar.gz
+RUN easy-add --var version=0.5.0 --var app=mc-monitor --file {{.app}} --from https://github.com/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_linux_${TARGETARCH}.tar.gz
 
 COPY *.sh /opt/