add docker build workflow (#39)

Author: lihebi

.github/workflows/docker-build.yml

@@ -0,0 +1,63 @@
+name: ci
+
+on:
+  release:
+    types: [created, published]
+
+jobs:
+  docker:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - context: ./ui
+            image: ${{ secrets.DOCKER_HUB_USERNAME }}/codepod-ui
+          - context: ./api
+            image: ${{ secrets.DOCKER_HUB_USERNAME }}/codepod-api
+          - context: ./proxy
+            image: ${{ secrets.DOCKER_HUB_USERNAME }}/codepod-proxy
+          - context: ./runtime/kernel
+            image: ${{ secrets.DOCKER_HUB_USERNAME }}/codepod-kernel-python
+          - context: ./runtime
+            image: ${{ secrets.DOCKER_HUB_USERNAME }}/codepod-runtime
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      -
+        name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          # list of Docker images to use as base name for tags
+          images: |
+            ${{ matrix.image }}
+          # generate Docker tags based on the following events/attributes
+          tags: |
+            type=schedule
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+            type=sha
+      -
+        name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+      -
+        name: Login to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      
+      - name: Build and push
+        uses: docker/build-push-action@v3
+        with:
+          context: ${{ matrix.context }}
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}