Add a GitHub workflow to automatically build and push to a public Docker registry

Author: dreglad

.github/workflows/ci.yml

@@ -0,0 +1,53 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+    tags: [v*]
+  pull_request:
+    branches: [main]
+  release:
+    types: [published]
+
+env:
+  REGISTRY: ghcr.io
+  REPOSITORY: ${{ github.repository }}
+
+jobs:
+  docker-image:
+    name: Build and push Docker image
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v1
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.REPOSITORY }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+
+      - name: Build and push ${{ env.REGISTRY }}/${{ env.REPOSITORY }} image
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          push: true