Add GitHub container build workflow

.github/workflows/container-image.yml

@@ -0,0 +1,60 @@
+name: Container Image
+
+on:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+    tags:
+      - 'v*'
+  workflow_dispatch:
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to GHCR
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract image metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+            type=sha
+            type=raw,value=latest,enable=${{ github.ref == 'refs/heads/main' }}
+
+      - name: Build and publish image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          platforms: linux/amd64
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

README.md

@@ -182,6 +182,29 @@ podman compose run --rm -e CONTAINER_RUN_MODE=once journey-fm-playlist
 podman compose logs -f journey-fm-playlist
 ```
 
+## GitHub Container Build
+
+GitHub Actions now builds the container on every pull request to `main` and on every push to `main`.
+Pushes to `main` also publish the image to GitHub Container Registry.
+
+Image location:
+
+```text
+ghcr.io/nmemmert/journey-fm-playlist
+```
+
+Pull with Podman:
+
+```bash
+podman pull ghcr.io/nmemmert/journey-fm-playlist:latest
+```
+
+If the package is private, authenticate first:
+
+```bash
+podman login ghcr.io
+```
+
 Notes:
 
 - The container uses Chromium + chromedriver in headless mode.