ci(docker): publish to ghcr

.github/workflows/docker-publish.yml

@@ -0,0 +1,53 @@
+name: Build and Deploy Docker to GHCR
+
+# This workflow runs when any of the following occur:
+# - A push is made to a branch called `main`
+# - A tag starting with "v" is created
+on:
+  push:
+    branches:
+      - main
+    tags:
+      - v*
+env:
+  IMAGE_NAME: stoic_quotes
+#
+jobs:
+  # This pushes the image to GitHub Packages.
+  push:
+    runs-on: ubuntu-latest
+
+    permissions:
+      packages: write
+      contents: read
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Build image
+        run: docker build . --file Dockerfile --tag $IMAGE_NAME --label "runnumber=${GITHUB_RUN_ID}"
+
+      - name: Log in to registry
+        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u $ --password-stdin
+
+      - name: Push image
+        run: |
+          IMAGE_ID=ghcr.io/${{ github.repository_owner }}/$IMAGE_NAME
+
+          # This changes all uppercase characters to lowercase.
+          IMAGE_ID=$(echo $IMAGE_ID | tr '[A-Z]' '[a-z]')
+
+          # This strips the git ref prefix from the version.
+          VERSION=$(echo "${{ github.ref }}" | sed -e 's,.*/\(.*\),\1,')
+
+          # This strips the "v" prefix from the tag name.
+          [[ "${{ github.ref }}" == "refs/tags/"* ]] && VERSION=$(echo $VERSION | sed -e 's/^v//')
+
+          # This uses the Docker `latest` tag convention.
+          [ "$VERSION" == "main" ] && VERSION=latest
+
+          echo IMAGE_ID=$IMAGE_ID
+          echo VERSION=$VERSION
+          docker tag $IMAGE_NAME $IMAGE_ID:$VERSION
+          docker push $IMAGE_ID:$VERSION
+