docker: add and use Openj9 as the latest image.

.github/workflows/docker-build.yml

@@ -8,7 +8,7 @@ on:
       - master
 
 jobs:
-  build-docker:
+  build-docker-hotspot:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
@@ -35,4 +35,32 @@ jobs:
           file: ./Dockerfile
           platforms: linux/amd64,linux/arm64
           push: true
-          tags: 1337kavin/piped:latest
+          tags: 1337kavin/piped:hotspot
+  build-docker-openj9:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+        with:
+          platforms: all
+      - name: Set up Docker Buildx
+        id: buildx
+        uses: docker/setup-buildx-action@v1
+        with:
+          version: latest
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          file: ./Dockerfile.openj9
+          platforms: linux/amd64
+          push: true
+          tags: 1337kavin/piped:latest,1337kavin/piped:openj9

Dockerfile.openj9

@@ -0,0 +1,17 @@
+FROM adoptopenjdk/openjdk11-openj9:slim AS build
+
+WORKDIR /app/
+
+COPY . /app/
+
+RUN chmod +x ./gradlew && ./gradlew shadowJar
+
+FROM adoptopenjdk/openjdk11-openj9:jre
+
+WORKDIR /app/
+
+COPY --from=build /app/build/libs/piped-1.0-all.jar /app/piped.jar
+
+EXPOSE 8080
+
+CMD java -jar /app/piped.jar