This is the wp-config.php supplied by Pantheon to allow automagic operation with WordPress

wp-config.php

<?php
/**
 * This config file is yours to hack on. It will work out of the box on Pantheon
 * but you may find there are a lot of neat tricks to be used here.
 *
 * See our documentation for more details:
 *
 * http://helpdesk.getpantheon.com/
 */

/**
 * Local configuration information.
 *
 * If you are working in a local/desktop development environment and want to
 * keep your config separate, we recommend using a 'wp-config-local.php' file,
 * which you should also make sure you .gitignore.
 */
if (dirname(__FILE__) . file_exists('wp-config-local.php') && !isset($_ENV['PANTHEON_ENVIRONMENT'])):
  # IMPORTANT: ensure your local config does not include wp-settings.php
  require_once(dirname(__FILE__) . '/wp-config-local.php');

/**
 * Pantheon platform settings. Everything you need should already be set.
 */
else:
  if (isset($_ENV['PANTHEON_ENVIRONMENT'])):
    // ** MySQL settings - included in the Pantheon Environment ** //
    /** The name of the database for WordPress */
    define('DB_NAME', $_ENV['DB_NAME']);

    /** MySQL database username */
    define('DB_USER', $_ENV['DB_USER']);

    /** MySQL database password */
    define('DB_PASSWORD', $_ENV['DB_PASSWORD']);

    /** MySQL hostname; on Pantheon this includes a specific port number. */
    define('DB_HOST', $_ENV['DB_HOST'] . ':' . $_ENV['DB_PORT']);

    /** Database Charset to use in creating database tables. */
    define('DB_CHARSET', 'utf8');

    /** The Database Collate type. Don't change this if in doubt. */
    define('DB_COLLATE', '');

    /**#@+
     * Authentication Unique Keys and Salts.
     *
     * Change these to different unique phrases!
     * You can generate these using the {@link https://api.wordpress.org/secret-key/1.1/salt/ WordPress.org secret-key service}
     * You can change these at any point in time to invalidate all existing cookies. This will force all users to have to log in again.
     *
     * Pantheon sets these values for you also. If you want to shuffle them you
     * can do so via your dashboard.
     *
     * @since 2.6.0
     */
    define('AUTH_KEY',         $_ENV['AUTH_KEY']);
    define('SECURE_AUTH_KEY',  $_ENV['SECURE_AUTH_KEY']);
    define('LOGGED_IN_KEY',    $_ENV['LOGGED_IN_KEY']);
    define('NONCE_KEY',        $_ENV['NONCE_KEY']);
    define('AUTH_SALT',        $_ENV['AUTH_SALT']);
    define('SECURE_AUTH_SALT', $_ENV['SECURE_AUTH_SALT']);
    define('LOGGED_IN_SALT',   $_ENV['LOGGED_IN_SALT']);
    define('NONCE_SALT',       $_ENV['NONCE_SALT']);
    /**#@-*/

    /** A couple extra tweaks to help things run well on Pantheon. **/
    if (isset($_SERVER['HTTP_HOST'])) {
      define('WP_HOME', 'http://' . $_SERVER['HTTP_HOST']);
      define('WP_SITEURL', 'http://' . $_SERVER['HTTP_HOST']);
    }
    // Don't show deprecations; useful under PHP 5.5
    error_reporting(E_ALL ^ E_DEPRECATED);


  else:
    /**
     * This block will be executed if you have no wp-config-local.php and you are
     * not running on Pantheon. Insert your own config here if necessary.
     *
     * If you are only running on Pantheon, you don't need to edit this at all.
     */
    define('DB_NAME',          'database_name');
    define('DB_USER',          'database_username');
    define('DB_PASSWORD',      'database_password');
    define('DB_HOST',          'database_host');
    define('DB_CHARSET',       'utf8');
    define('DB_COLLATE',       '');
    define('AUTH_KEY',         'put your unique phrase here');
    define('SECURE_AUTH_KEY',  'put your unique phrase here');
    define('LOGGED_IN_KEY',    'put your unique phrase here');
    define('NONCE_KEY',        'put your unique phrase here');
    define('AUTH_SALT',        'put your unique phrase here');
    define('SECURE_AUTH_SALT', 'put your unique phrase here');
    define('LOGGED_IN_SALT',   'put your unique phrase here');
    define('NONCE_SALT',       'put your unique phrase here');
  endif;

  /** Standard wp-config.php stuff from here on down. **/

  /**
   * WordPress Database Table prefix.
   *
   * You can have multiple installations in one database if you give each a unique
   * prefix. Only numbers, letters, and underscores please!
   */
  $table_prefix  = 'wp_';

  /**
   * WordPress Localized Language, defaults to English.
   *
   * Change this to localize WordPress. A corresponding MO file for the chosen
   * language must be installed to wp-content/languages. For example, install
   * de_DE.mo to wp-content/languages and set WPLANG to 'de_DE' to enable German
   * language support.
   */
  define('WPLANG', '');

  /**
   * For developers: WordPress debugging mode.
   *
   * Change this to true to enable the display of notices during development.
   * It is strongly recommended that plugin and theme developers use WP_DEBUG
   * in their development environments.
   *
   * You may want to examine $_ENV['PANTHEON_ENVIRONMENT'] to set this to be
   * "true" in dev, but false in test and live.
   */
  define('WP_DEBUG', false);

  /* That's all, stop editing! Happy blogging. */
endif;



/** Absolute path to the WordPress directory. */
if ( !defined('ABSPATH') )
	define('ABSPATH', dirname(__FILE__) . '/');

/** Sets up WordPress vars and included files. */
require_once(ABSPATH . 'wp-settings.php');