github action and readme update

Author: jphenow

.github/workflows/build-and-push.yml

@@ -0,0 +1,39 @@
+name: Build and Push Docker Image
+
+on:
+  push:
+    branches:
+      - main
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}/mpg-operator-postgres
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

README.md

@@ -13,8 +13,7 @@ This image works with the Percona PostgreSQL Operator architecture:
 1. Patroni is the process manager that starts and manages PostgreSQL
 2. Our wrapper script sets the OOM score adjustment to -1000 for the Patroni process
 3. This adjustment is inherited by PostgreSQL processes, protecting them from OOM killer
-4. Custom PostgreSQL configuration is provided to optimize memory usage
-5. The wrapper script preserves the original entrypoint behavior of the parent image
+4. The wrapper script preserves the original entrypoint behavior of the parent image
 
 ## Usage
 
@@ -25,6 +24,29 @@ docker build -t oom-protected-postgres .
 docker run -d --name postgres oom-protected-postgres
 ```
 
+## Continuous Integration / Deployment
+
+This repository includes a GitHub Action that automatically builds and pushes the Docker image to GitHub Container Registry (ghcr.io) whenever changes are pushed to the main branch.
+
+### Automated Builds
+
+The workflow:
+1. Builds the Docker image
+2. Tags it with both `latest` and the short commit SHA
+3. Pushes it to GitHub Container Registry
+
+### Using the Pre-built Image
+
+Once built, you can pull the image directly:
+
+```bash
+docker pull ghcr.io/[your-username]/mpg-postgres-image/oom-protected-postgres:latest
+```
+
+### GitHub Action Configuration
+
+The GitHub Action configuration is defined in `.github/workflows/build-and-push.yml`. If you fork this repository, you'll need to ensure your repository has permission to push packages. You can configure this in your repository settings under "Actions" > "General" > "Workflow permissions".
+
 ## References
 
 - [PostgreSQL documentation on kernel resources](https://www.postgresql.org/docs/current/kernel-resources.html)