add workflow for docker on github registry

.github/workflows/docker-publish.yml

@@ -0,0 +1,109 @@
+name: Build and Publish Docker Image
+
+on:
+  push:
+    branches:
+      - main
+      - feature/docker-github-registry
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Image tag (default: latest)'
+        required: false
+        default: 'latest'
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: aihpi/ragsst
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build Docker image (test)
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: false
+          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:test
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+
+  publish:
+    needs: build-and-test
+    runs-on: ubuntu-latest
+    # Only publish from main branch or manual workflow dispatch
+    if: github.ref == 'refs/heads/main' || github.event_name == 'workflow_dispatch'
+
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=raw,value=latest,enable={{is_default_branch}}
+            type=raw,value=${{ github.event.inputs.tag || 'latest' }}
+            type=sha,prefix={{branch}}-
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+          build-args: |
+            BUILD_DATE=${{ github.event.head_commit.timestamp }}
+            VCS_REF=${{ github.sha }}
+            VERSION=${{ github.event.inputs.tag || 'latest' }}
+
+      - name: Generate image summary
+        run: |
+          echo "### Docker Image Published! 🐳" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "**Registry:** \`${{ env.REGISTRY }}\`" >> $GITHUB_STEP_SUMMARY
+          echo "**Image:** \`${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}\`" >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "**Tags:**" >> $GITHUB_STEP_SUMMARY
+          echo "${{ steps.meta.outputs.tags }}" | sed 's/^/- /' >> $GITHUB_STEP_SUMMARY
+          echo "" >> $GITHUB_STEP_SUMMARY
+          echo "**Platforms:** linux/amd64, linux/arm64" >> $GITHUB_STEP_SUMMARY

Dockerfile

@@ -20,6 +20,12 @@ RUN pip install --no-cache-dir uv && \
 COPY app.py ./
 COPY ragsst ./ragsst
 
+# Add metadata labels for GitHub Container Registry
+LABEL org.opencontainers.image.source="https://github.com/aihpi/ragsst"
+LABEL org.opencontainers.image.description="RAGSST - Retrieval Augmented Generation and Semantic-Search Tool"
+LABEL org.opencontainers.image.licenses="GPL-3.0"
+LABEL org.opencontainers.image.documentation="https://github.com/aihpi/ragsst/blob/main/README.md"
+
 # Expose port
 EXPOSE 7860
 

docker-compose.yml

@@ -10,10 +10,13 @@ services:
 
   # RAGSST App
   ragsst-app:
+      # Use pre-built image from GitHub Container Registry (for workshop participants)
+      image: ghcr.io/aihpi/ragsst:latest
+      # Uncomment the lines below to build locally instead of using pre-built image
+      # build:
+      #   context: ./
+      #   dockerfile: Dockerfile
       container_name: ragsst-app
-      build:
-        context: ./
-        dockerfile: Dockerfile
       ports:
         - "7860:7860"
       volumes: