adds github action to build and push docker image

.github/workflows/docker-image.yml

@@ -2,17 +2,33 @@ name: Docker Image CI
 
 on:
   push:
-    branches: [ "main" ]
-  pull_request:
-    branches: [ "main" ]
-
+    branches:
+      - main
 jobs:
-
-  build:
-
-    runs-on: python:3-slim
-
+  docker:
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+    runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
-    - name: Build the Docker image
-      run: docker build . --file Dockerfile --tag sungather:$(date +%s)
+      -
+        name: Checkout
+        uses: actions/checkout@v2
+      -
+        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: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          platforms: linux/amd64,linux/arm64,linux/arm/v7
+          push: true
+          tags: ${{ secrets.DOCKERHUB_USERNAME }}/sungather:latest