wp-config.php

<?php
    define('DB_USER',          getenv('WORDPRESS_DB_USER')        ?: 'wordpress');
    define('DB_NAME',          getenv('WORDPRESS_DB_NAME')        ?: 'wordpress');
    define('DB_PASSWORD',      getenv('WORDPRESS_DB_PASSWORD')    ?: 'wordpress');
    define('DB_HOST',          getenv('WORDPRESS_DB_HOST')        ?: 'mysql');
    define('DB_CHARSET',       getenv('WORDPRESS_DB_CHARSET')     ?: 'utf8');
    define('DB_COLLATE',       getenv('WORDPRESS_DB_COLLATE')     ?: '');

    define('AUTH_KEY',         getenv('WORDPRESS_AUTH_KEY'));
    define('SECURE_AUTH_KEY',  getenv('WORDPRESS_SECURE_AUTH_KEY'));
    define('LOGGED_IN_KEY',    getenv('WORDPRESS_LOGGED_IN_KEY'));
    define('NONCE_KEY',        getenv('WORDPRESS_NONCE_KEY'));
    define('AUTH_SALT',        getenv('WORDPRESS_AUTH_SALT'));
    define('SECURE_AUTH_SALT', getenv('WORDPRESS_SECURE_AUTH_SALT'));
    define('LOGGED_IN_SALT',   getenv('WORDPRESS_LOGGED_IN_SALT'));
    define('NONCE_SALT',       getenv('WORDPRESS_NONCE_SALT'));

    define('FS_METHOD',        getenv('WORDPRESS_FS_METHOD')      ?: 'direct');

    $table_prefix  =           getenv('WORDPRESS_TABLE_PREFIX')   ?: 'wp_';
    define('WP_DEBUG',         getenv('WORDPRESS_DEBUG')         === 'true');
    define('WP_DEBUG_LOG',     getenv('WORDPRESS_DEBUG_LOG')     === 'true');
    define('WP_DEBUG_DISPLAY', getenv('WORDPRESS_DEBUG_DISPLAY') === 'true');

    define('WP_ALLOW_MULTISITE', getenv('WORDPRESS_MULTISITE') === 'true');

    if(getenv('WORDPRESS_MULTISITE_INSTALLED') === 'true')
    {
        define('MULTISITE', true);
        define('SUBDOMAIN_INSTALL', true);
        define('DOMAIN_CURRENT_SITE', getenv('WORDPRESS_BASEURL') ?: 'example.com');
        define('PATH_CURRENT_SITE', '/');
        define('SITE_ID_CURRENT_SITE', 1);
        define('BLOG_ID_CURRENT_SITE', 1);
        /**
          *      Redirect to page below when user try to access
          *      a subdomain that doesn't exist.
          */
        define('NOBLOGREDIRECT', getenv('WORDPRESS_NOBLOGREDIRECT') ?: getenv('WORDPRESS_BASEURL') ?: 'example.com');

        if(@file_exists('wp-content/sunrise.php') || ( defined('ABSPATH') && @file_exists('ABSPATH'.'wp-content/sunrise.php') ) define( 'SUNRISE', 'on' );
    }
    
    if ( !WP_DEBUG_LOG ) {
        ini_set('log_errors', 1);
        ini_set('error_log', 'php://stderr');
    }

    if ( !defined('ABSPATH') ) {
        define('ABSPATH', dirname(__FILE__) . '/');
    }

    if(getenv('HTTPS') === 'on') {
        $_SERVER['HTTPS'] = 'on';
    }

    if (isset($_SERVER['HTTP_X_FORWARDED_PROTO'])
        && strpos($_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false) {
      $_SERVER['HTTPS'] = 'on';
    }

    foreach(glob(ABSPATH . 'wp-config.d/*.php') as $config) {
        include($config);
    }

    require_once(ABSPATH . 'wp-settings.php');