emcniece/wordpress

Github: https://github.com/emcniece/docker-wordpress Docker Hub: https://hub.docker.com/r/emcniece/wordpress/

From WordPress, extended with Nginx Helper and Redis Object Cache support.

Inherits regular setup from the WordPress Docker image.

PHP-FPM only - requires a partner Nginx container to forward traffic to port 9000.

Installing Plugins

The WP_PLUGINS environment variable can be set to preload plugins into the wp-content/plugins/ directory. By default it is set to WP_PLUGINS="nginx-helper redis-cache" as these plugins are core to the operation of this container. Plugins will only be installed the first time the container is run.

To add more plugins, modify the variable at runtime:

docker run -td \
  -v ./html:/var/www/html \
  -e "WP_PLUGINS=nginx-helper redis-cache mailgun my-other-plugin"
  emcniece/wordpress:4-php7.1-fpm-alpine

... or in docker-compose.yml:

  wp-fpm:
    tty: true
    stdin_open: true
    image: emcniece/wordpress:latest
    volumes:
      - wproot:/var/www/html
    environment:
      WORDPRESS_DB_HOST: mysql
      WORDPRESS_DB_USER: wordpress
      WORDPRESS_DB_PASSWORD: wordpress
      WPFPM_WP_REDIS_HOST: redis
      WPFPM_RT_WP_NGINX_HELPER_CACHE_PATH: "/tmp/cache"
      WP_PLUGINS: "nginx-helper redis-cache mailgun my-other-plugin"

Recommended Environment

Recognized environment variables:

ENABLE_HYPERDB: Installs HyperDB config on first run, [true|false]
- eg. ENABLE_HYPERDB=true
WP_PLUGINS: space-separated plugin directory names, to be installed from the WP plugin marketplace
- eg. WP_PLUGINS="nginx-helper redis-cache"
ENABLE_CRON: Enables crond daemon in background (logs to container stdout)
- eg. ENABLE_CRON=true
CRON_CMD: Cron command to be added to crontab on startup
- eg. CRON_CMD="*/10 * * * * /usr/bin/ls -al /root"

Runtime ENV wp-config.php Injection

Any environment variables prefixed with WPFPM_ will be injected into wp-config.php during each container startup. Warning: this means that wp-config.php is regenerated each restart using the provided environment variables.

The provided docker-compose.yml file injects 2 variables into wp-config.php:

WPFPM_WP_REDIS_HOST: redis # Name of the Redis container
WPFPM_RT_WP_NGINX_HELPER_CACHE_PATH: "/tmp/cache" # Set in emcniece/nginx-cache-purge-wp default.conf

HyperDB Configuration

The HyperDB drop-in allows a replica database to be configured alongside the primary database.

When ENABLE_HYPERDB=true the HyperDB config files will be copied into place and will override the database config provided in wp-config.php. The HyperDB replica database can be configured with the following environment variables:

REPLICA_DB_HOST
REPLICA_DB_USER
REPLICA_DB_PASSWORD
REPLICA_DB_NAME

SSL Forwarding

The docker-entrypoint2.sh script also injects the PHP HTTP_X_FORWARDED_PROTO variable to allow for an SSL certificate to be terminated upstream while maintaining data communication into the container. This is useful in infrastructure with load balancers or reverse proxies, eg:

Internet -> Nginx proxy w/ SSL termination -> emcniece/nginx-cache-purge-wp -> emcniece/wordpress

Quick Run

If you want to use the standalone FPM (port 9000) image:

docker run -td \
  -v ./html:/var/www/html \
  emcniece/wordpress:4-php7.1-fpm-alpine

If you want to run a full web-accessible stack (Nginx, WP-FPM, MySQL, Redis):

docker-compose up -d

To Do

Imagick / LibZip PHP Extensions (courtesy of wordpress:5-php7.2-fpm-alpine)
HyperDB config: allow read/write to be set for both primary and replica databases
HyperDB config: replace current ENV vars with WPFPM_ injection pattern