How to update wordpress on docker

Question

I'm running a php-fpm wordpress container.

The wordpress source files are mounted in a named volume "wordpress" shared with the Nginx container.

Everything is running well except when i need to update wordpress to a new version. The code inside the named volume persists. It is normal for a named volume...

I could manually delete the volume but there must be a better way.

My dockerfile:

FROM wordpress:4.9.5-php5.6-fpm-alpine

My docker-compose.yml

version: '3.1'

services:

  php:
    build: ./docker/php/
    restart: unless-stopped
    volumes:
      - wordpress:/var/www/html
      - ./web/wp-content/:/var/www/html/wp-content/
      - ./web/wp-config.php:/var/www/html/wp-config.php

    environment:
      - DEBUG=${DEBUG:-0}
      - MYSQL_USER=$MYSQL_USER
      - MYSQL_PASSWORD=$MYSQL_PASSWORD
      - MYSQL_DATABASE=$MYSQL_DATABASE

  nginx:
    image: nginx:1-alpine
    restart: unless-stopped
    expose:
      - 80
    volumes:
      - wordpress:/var/www/html
      - ./web/wp-content/:/var/www/html/wp-content/
      - ./docker/nginx/site.conf:/etc/nginx/conf.d/default.conf
      - ./docker/nginx/wordpress.conf:/etc/nginx/wordpress.conf
    environment:
      - VIRTUAL_HOST=localhost

  mysql:
    image: mysql:5.6
    restart: unless-stopped
    environment:
      - MYSQL_ROOT_PASSWORD=$MYSQL_ROOT_PASSWORD
      - MYSQL_USER=$MYSQL_USER
      - MYSQL_PASSWORD=$MYSQL_PASSWORD
      - MYSQL_DATABASE=$MYSQL_DATABASE
    volumes:
      - mysql:/var/lib/mysql

volumes:
  wordpress: {}
  mysql: {}

networks:
  default:
    external:
      name: wordpress

Looking forward to reading your suggestions

Thank you

Answer 1

My answer applied to the official docker wordpress image. So probably off topic but might help someone.

If you are using docker-compose you can pull the latest image using this command.

docker pull wordpress

I believe this will update your core docker image. Any other local project which you docker-compose up -d with this yml image setting as this will use the latest update.

  services:
    wordpress:
      image: wordpress:latest

If you currently running the image will you need to docker-compose down and docker-compose up -d to invoke the update.

Answer 2

Wordpress seems to have addressed this under this issue.

I notice you are using a custom wp-config.php. Most likely, you can use the WORDPRESS_CONFIG_EXTRA for this rather than mounting wp-config.php.

Theoretically (per the link above), updating the image should update the database, but I have not confirmed.

Based on this, my stack.yml/docker-compose.yml looks like this:

    environment:
      WORDPRESS_CONFIG_EXTRA: |
        define( 'AUTOMATIC_UPDATER_DISABLED', true );
    volumes:
      - "./themes:/var/www/html/wp-content/themes/"
      - "./plugins:/var/www/html/wp-content/plugins/"
      - "./uploads:/var/www/html/wp-content/uploads/"