Lately, I’ve been trying to Dockerize my WordPress instance using 3 containers, one for nginx, another for mariadb and one for WordPress itself. But I simply can’t get it to work. For starters, every time WordPress has to call any plugin function it throws:

Fatal error: Uncaught Error: Call to undefined function

Besides, I can’t access some pages, for example if I try to access the index.php page I get page not found. However, I can access some pages directly, like wp-login.php.

Here is Nginx container:

Here is my WordPress container:

My docker-compose.yaml

version: '3.8'
services:
  wp_db:
    build: ./db
    container_name: db_wp
    restart: always
    expose:
      - 3306
    environment:
      MYSQL_ROOT_PASSWORD: password
      MYSQL_DATABASE: wpdb
      MYSQL_USER: user
      MYSQL_PASSWORD: password
  
  wp:
    depends_on:
      - wp_db
    image: wordpress:6.2.1-fpm-alpine
    ports:
      - "9000:9000"
    container_name: wordpress
    restart: unless-stopped
    volumes:
      - ./wp:/var/www/html
  webserver:
    depends_on:
      - wp
    image: nginx:1.15.12-alpine
    container_name: webserver
    restart: unless-stopped
    ports:
      - "81:80"
    volumes:
      - ./nginx:/etc/nginx/conf.d
      - ./wp:/var/www/html

Here is my nginx.conf file:

 server {
  listen 80;
  listen [::]:80;
  access_log off;
  root /var/www/html;
  index index.php;
  server_tokens off;
  location / {
    # First attempt to serve request as file, then
    # as directory, then fall back to displaying a 404.
    try_files $uri $uri/ /index.php?$args;
  }
  location /wp-admin {
            # This is cool because no php is touched for static content.
            # include the "?$args" part so non-default permalinks doesn't break when using query string
          try_files $uri $uri/ /wp-admin/index.php?$args;
    }
  # pass the PHP scripts to FastCGI server listening on wordpress:9000
  location ~ .php$ {
    fastcgi_split_path_info ^(.+.php)(/.+)$;
    fastcgi_pass wordpress:9000;
    include fastcgi_params;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    fastcgi_param SCRIPT_NAME $fastcgi_script_name;
  }
}

I tried changing ownership and permissions, but it still doesn’t work.