Add GitHub workflow for blog image

Author: AnastaZIuk

.github/workflows/docker-publish.yml

@@ -0,0 +1,104 @@
+name: Build and Publish Blog Image
+
+concurrency:
+  group: blog-build-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  push:
+    branches: [master]
+    tags: ["v*"]
+  pull_request:
+  workflow_dispatch:
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: "www-blog"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Compute image name (lowercase owner/repo)
+        id: img
+        run: |
+          OWNER="$(echo "${GITHUB_REPOSITORY_OWNER}" | tr '[:upper:]' '[:lower:]')"
+          REPO_NAME="${GITHUB_REPOSITORY##*/}"
+          IMAGE_NAME="${IMAGE_NAME:-$REPO_NAME}"
+          IMAGE_NAME="$(echo "${IMAGE_NAME}" | tr '[:upper:]' '[:lower:]')"
+          echo "IMAGE=${REGISTRY}/${OWNER}/${IMAGE_NAME}" >> "$GITHUB_ENV"
+
+      - name: Docker metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.IMAGE }}
+          tags: |
+            type=sha
+            type=ref,event=tag
+            type=ref,event=branch,enable=${{ github.ref == 'refs/heads/master' }}
+            type=raw,value=latest,enable=${{ github.ref == 'refs/heads/master' }}
+
+      - name: Set up Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build image for tests
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          push: false
+          load: true
+          tags: ${{ env.IMAGE }}:ci
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+      - name: Run smoke test (curl /)
+        env:
+          IMAGE_UNDER_TEST: ${{ env.IMAGE }}:ci
+        run: |
+          set -euo pipefail
+          cid=$(docker run -d -p 0:3000 "$IMAGE_UNDER_TEST")
+          trap "docker rm -f $cid >/dev/null 2>&1" EXIT
+          port=$(docker inspect -f '{{ (index (index .NetworkSettings.Ports "3000/tcp") 0).HostPort }}' "$cid")
+          if [ -z "$port" ]; then
+            echo "Failed to resolve mapped port for container $cid" >&2
+            docker logs "$cid" || true
+            exit 1
+          fi
+          for i in {1..20}; do
+            if curl -fsS "http://127.0.0.1:${port}/" > /dev/null; then
+              exit 0
+            fi
+            sleep 1
+          done
+          echo "Service did not respond on / after 20s" >&2
+          docker logs "$cid" || true
+          exit 1
+
+      - name: Log in to GHCR
+        if: github.event_name == 'push' && (startsWith(github.ref, 'refs/heads/master') || startsWith(github.ref, 'refs/tags/'))
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.CR_PAT != '' && secrets.CR_PAT || secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        if: github.event_name == 'push' && (startsWith(github.ref, 'refs/heads/master') || startsWith(github.ref, 'refs/tags/'))
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max