add workflow to publish docker image (#369)

* add workflow to publish docker image

This workflow intended to be triggered manually from the Actions tab.

* Push to trigger docker workflow

* update

* update

* resolve #366

* update

* add release tag to docker image

* publish docker image on release or manual

* echo tag in output

* update

* trigger

* update

* update

* fetch tags

* simplify loop, debug output

* update to checkout@v4

* revert back to checkout@v3, add explicit fetch

* remove shallow

* update

* update

* Update docker.yml

* clean up

* Update docker.yml

.github/workflows/docker.yml

@@ -0,0 +1,55 @@
+name: Build and Publish Docker image to GHCR
+
+on:
+  workflow_dispatch: # allows manual triggers via the GitHub UI
+  release:
+    types:
+      - published
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    # Checkout the repository
+    - name: Checkout repository
+      uses: actions/checkout@v3
+      with:
+        ref: main
+
+    # Fetch all tags
+    - name: Fetch tags
+      run: |
+        git fetch --prune --tags
+    
+    # Set up Docker Buildx for cross-platform builds (optional but recommended)
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v3
+
+    # Log in to the GitHub Container Registry
+    - name: Log in to GHCR
+      uses: docker/login-action@v3
+      with:
+        registry: ghcr.io
+        username: ${{ github.actor }}
+        password: ${{ secrets.GITHUB_TOKEN }}
+
+    # Build and tag the Docker image
+    - name: Build Docker image
+      run: |
+        cd hefquin-docker/
+        docker build -t ghcr.io/liusemweb/hefquin:latest .
+    
+    - name: Tag and push Docker image
+      run: |
+        # Get the tags for the current commit and add to image
+        # Loop tags
+        tags=$(git tag --points-at HEAD)
+        for tag in $tags; do
+          echo "Adding tag: $tag"
+          docker tag ghcr.io/liusemweb/hefquin:latest ghcr.io/liusemweb/hefquin:$tag
+        done
+
+    # Push the Docker image to GitHub Container Registry (GHCR)
+    - name: Push Docker image to GHCR
+      run: |
+        docker push ghcr.io/liusemweb/hefquin --all-tags