ci: auto build docker image

.github/workflows/build_docker.yml

@@ -0,0 +1,39 @@
+name: build_docker
+
+on:
+  push:
+    branches: [ main ]
+
+jobs:
+  build_docker:
+    name: Docker
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: xhofe/alist
+      - name: Replace release with dev
+        run: |
+          sed -i 's/release/dev/g' Dockerfile
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: xhofe
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Build and push
+        id: docker_build
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          platforms: linux/amd64,linux/arm64,linux/arm/v7,linux/386,linux/arm/v6,linux/s390x