Multi-environment wp-config

wp-config.php

// Get the host
$host = $_SERVER['HTTP_HOST'];

// Define the site base
$site_base = 'example.com';

// WP subdirectory
$wp_subdirectory = '';

if( $host === 'local.' . $site_base || $host === 'localhost:8888' ){

	// Enable debugging
	error_reporting(E_ALL);
	ini_set('display_errors', '1');

	// Create a variable to identify what the environment is 
	define('WP_ENV', 'local');
	
	// ** MySQL settings - You can get this info from your web host ** //
	/** The name of the database for WordPress */
	define('DB_NAME', '');

	/** MySQL database username */
	define('DB_USER', '');

	/** MySQL database password */
	define('DB_PASSWORD', '');

	/** MySQL hostname */
	define('DB_HOST', '');
	
	// Define the Home URL ( the url of the home page) 
	define('WP_HOME','http://local.' . $site_base);
	
	// Define the Site URL (the url of the WordPress installation)
	define('WP_SITEURL','http://local.' . $site_base . $wp_subdirectory);
	
} elseif( $host === 'dev.' . $site_base ){

	// Enable debugging
	error_reporting(E_ALL);
	ini_set('display_errors', '1');

	// Create a variable to identify what the environment is 
	define('WP_ENV', 'dev');
		
	// ** MySQL settings - You can get this info from your web host ** //
	/** The name of the database for WordPress */
	define('DB_NAME', '');

	/** MySQL database username */
	define('DB_USER', '');

	/** MySQL database password */
	define('DB_PASSWORD', '');
	
	/** MySQL hostname */
	define('DB_HOST', '');
	
	// Define the Home URL ( the url of the home page) 
	define('WP_HOME','http://dev.' . $site_base);
	
	// Define the Site URL (the url of the WordPress installation)
	define('WP_SITEURL','http://dev.' . $site_base . $wp_subdirectory);
	
} elseif( $host === 'staging.' . $site_base ){

	// Enable debugging
	error_reporting(E_ALL);
	ini_set('display_errors', '1');

	// Create a variable to identify what the environment is 
	define('WP_ENV', 'staging');
		
	// ** MySQL settings - You can get this info from your web host ** //
	/** The name of the database for WordPress */
	define('DB_NAME', '');

	/** MySQL database username */
	define('DB_USER', '');

	/** MySQL database password */
	define('DB_PASSWORD', '');
	
	/** MySQL hostname */
	define('DB_HOST', '');
	
	// Define the Home URL ( the url of the home page) 
	define('WP_HOME','http://staging.' . $site_base);
	
	// Define the Site URL (the url of the WordPress installation)
	define('WP_SITEURL','http://staging.' . $site_base . $wp_subdirectory);
	
} elseif( $host === $site_base || $host === 'www.' . $site_base ){
	
	// Create a variable to identify what the environment is 
	define('WP_ENV', 'live');

	// ** MySQL settings - You can get this info from your web host ** //
	/** The name of the database for WordPress */
	define('DB_NAME', '');
	
	/** MySQL database username */
	define('DB_USER', '');
	
	/** MySQL database password */
	define('DB_PASSWORD', '');
	
	/** MySQL hostname */
	define('DB_HOST', '');
	
	// Define the Home URL ( the url of the home page) 
	define('WP_HOME','http://www.' . $site_base);
	
	// Define the Site URL (the url of the WordPress installation)
	define('WP_SITEURL','http://www.' . $site_base . $wp_subdirectory);
	
}