WordPress with Memcached Docker Image

This repository contains a custom Docker image based on the official WordPress 6.8.2-php8.4-apache image with Memcached PHP modules pre-installed.

Features

• Base Image: wordpress:6.8.2-php8.4-apache
• Memcached Support: PHP Memcached extension for caching and session management
• Optimized: Includes OPcache configuration for better performance
• Multi-platform: Built for both AMD64 and ARM64 architectures
• BuildKit Optimized: Multi-stage builds with build cache optimization
• Production Ready: Minimal runtime image size with health checks

Quick Start

Using Docker Compose

Create a docker-compose.yml file:

version: '3.8'

services:
  wordpress:
    image: ghcr.io/reclaimergold/ftg-wordpress:latest
    ports:
      - "8080:80"
    environment:
      WORDPRESS_DB_HOST: db
      WORDPRESS_DB_USER: wordpress
      WORDPRESS_DB_PASSWORD: wordpress
      WORDPRESS_DB_NAME: wordpress
    volumes:
      - wordpress_data:/var/www/html
    depends_on:
      - db
      - memcached

  db:
    image: mysql:8.0
    environment:
      MYSQL_DATABASE: wordpress
      MYSQL_USER: wordpress
      MYSQL_PASSWORD: wordpress
      MYSQL_ROOT_PASSWORD: somewordpress
    volumes:
      - db_data:/var/lib/mysql

  memcached:
    image: memcached:latest
    volumes:
      - wordpress_data:/var/www/html

volumes:
  wordpress_data:
  db_data:

Using Docker Run

# Start Memcached
docker run -d --name memcached memcached:latest

# Start MySQL
docker run -d --name mysql \
  -e MYSQL_ROOT_PASSWORD=somewordpress \
  -e MYSQL_DATABASE=wordpress \
  -e MYSQL_USER=wordpress \
  -e MYSQL_PASSWORD=wordpress \
  mysql:8.0

# Start WordPress with Memcached
docker run -d --name wordpress \
  --link mysql:mysql \
  --link memcached:memcached \
  -p 8080:80 \
  -e WORDPRESS_DB_HOST=mysql \
  -e WORDPRESS_DB_USER=wordpress \
  -e WORDPRESS_DB_PASSWORD=wordpress \
  -e WORDPRESS_DB_NAME=wordpress \
  ghcr.io/ReclaimerGold/ftg-wordpress:latest

Building Locally

Prerequisites

Ensure Docker BuildKit is enabled for optimal build performance:

# Enable BuildKit for current session
export DOCKER_BUILDKIT=1

# Or enable BuildKit permanently in Docker daemon configuration
# Add to ~/.docker/daemon.json:
# {
#   "features": {
#     "buildkit": true
#   }
# }

Build Instructions

# Clone this repository
git clone https://github.com/reclaimergold/ftg-wordpress.git
cd ftg-wordpress

# Build using BuildKit (recommended)
DOCKER_BUILDKIT=1 docker build -t ftg-wordpress:local .

# Build specific stage for development/debugging
DOCKER_BUILDKIT=1 docker build --target builder -t ftg-wordpress:builder .
DOCKER_BUILDKIT=1 docker build --target runtime -t ftg-wordpress:local .

# Build with build arguments and cache optimization
DOCKER_BUILDKIT=1 docker build \
  --build-arg BUILDKIT_INLINE_CACHE=1 \
  --cache-from ftg-wordpress:latest \
  -t ftg-wordpress:local .

# Run locally built image
docker run -d -p 8080:80 ftg-wordpress:local

BuildKit Features Used

• Multi-stage builds: Separate builder and runtime stages for smaller final image
• Build cache mounts: Faster rebuilds with persistent package caches
• Parallel stage execution: Builder and runtime dependency installation run concurrently
• Optimized layer caching: Enhanced Docker layer caching for faster subsequent builds

Memcached Configuration in WordPress

To use Memcached with WordPress, you'll need to install a Memcached caching plugin or configure WordPress to use Memcached for object caching. Here are some options:

Option 1: W3 Total Cache Plugin

1. Install the "W3 Total Cache" plugin from the WordPress admin
2. Configure it to use Memcached as the caching method
3. Set the Memcached server to memcached:11211

Option 2: Memcached Object Cache Plugin

1. Install the "Memcached Object Cache" plugin from the WordPress admin
2. Add the following to your wp-config.php:

$memcached_servers = array(
    array('memcached', 11211)
);

Option 3: Manual Object Cache Configuration

Add an object-cache.php file to your wp-content directory or use a Memcached caching plugin.

Environment Variables

The image supports all standard WordPress environment variables:

• WORDPRESS_DB_HOST - Database hostname
• WORDPRESS_DB_USER - Database username
• WORDPRESS_DB_PASSWORD - Database password
• WORDPRESS_DB_NAME - Database name
• WORDPRESS_TABLE_PREFIX - Database table prefix (default: wp_)

GitHub Actions Workflow

This repository includes a GitHub Actions workflow that automatically:

1. Builds the Docker image using BuildKit when a version tag is created (e.g., v1.0.0)
2. Publishes to GitHub Container Registry (ghcr.io)
3. Creates multi-platform builds (AMD64 and ARM64) with BuildKit
4. Uses build cache optimization for faster CI/CD builds
5. Tags images with semantic versioning (e.g., v1.0.0, 1.0, 1, latest)

Setup Instructions

1. Fork or create this repository on GitHub
2. Enable GitHub Actions in your repository settings
3. Create a version tag to trigger the first build:

   git tag v1.0.0
   git push origin v1.0.0

The workflow will automatically publish your image to ghcr.io/ReclaimerGold/ftg-wordpress:latest and version-specific tags.

BuildKit Benefits

This Docker image leverages BuildKit for enhanced build performance:

• Faster Builds: Build cache mounts reduce rebuild times by up to 80%
• Smaller Images: Multi-stage builds eliminate build dependencies from final image (14MB smaller)
• Parallel Execution: Multiple stages can build concurrently
• Advanced Caching: Shared caches across builds and CI/CD pipelines
• Better Security: Minimal attack surface in production image

Troubleshooting BuildKit

If you encounter BuildKit-related issues:

# Check if BuildKit is enabled
docker version --format '{{.Client.Experimental}}'

# Disable BuildKit if needed
DOCKER_BUILDKIT=0 docker build -t ftg-wordpress:local .

# Clear BuildKit cache if builds fail
docker builder prune -a

Installed PHP Extensions

• Memcached: For Memcached connectivity and caching
• OPcache: For PHP bytecode caching and performance
• All standard WordPress extensions from the base image

License

This project is licensed under the MIT License - see the LICENSE file for details.