add workflow to build & push to container registry

.github/workflows/build-push.yaml

@@ -0,0 +1,39 @@
+#
+name: Create and publish a Docker image
+
+on:
+  push:
+    branches: ['main']
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-and-push-image:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+      - name: Build and push Docker image
+        uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -1,15 +1,9 @@
-# small is beautiful
 FROM alpine:3.14
 
 LABEL maintainer="Nico Duldhardt <nico@duldhardt.com>"
 
-# The container listens on port 80, map as needed
 EXPOSE 80
 
-# This is where the repositories will be stored
-VOLUME ["/git"]
-
-# Install required packages
 RUN apk add --no-cache nginx git git-daemon fcgiwrap spawn-fcgi
 
 COPY nginx.conf /etc/nginx/nginx.conf