ConfigLoader.php

<?php

/**
 * ConfigLoader class file.
 * 
 * @author Petra Barus <petra.barus@gmail.com>
 * @package application.components
 * @since 2013.02.15
 */

/**
 * ConfigLoader handles hierarchical configuration file from configuration
 * directory.
 * 
 * A configuration directory will look like this.
 * 
 * protected/config/environments
 * +- default
 * |  +- application
 * |  |  +- components.php          //contains default components
 * |  |  +- params.php              //contains default params
 * |  +- application.php            //contains default config, e.g. application name, timezone, language.
 * +- web
 * |  +- application
 * |  |  +- urlManager.php          //contains default url manager or rules for web
 * |  +- application.php
 * +- console
 * |  +- application.php
 * +- test
 * |  +- application
 * |  |  +- components
 * |  |  |  +- db.php               //contains default database for testing
 * |  +- application.php
 * +- development
 * |  +- application
 * |  |  +- components
 * |  |     +- clientScript
 * |  |        +- packages.php      //contains javascript packages for local development
 * |  +- application.php
 * +- production
 * |  +- application
 * |  |  +- components
 * |  |     +- clientScript
 * |  |        +- packages.php      //contains javascript packages for production
 * |  |     +- db.php               //contains default database for production
 * |  |     +- mailer.php           //contains default mailer components
 * |  +- application.php
 * +- console-production            //contains configuration for console production
 *    +- application
 *       +- components
 *          +- request.php          //contains request component configuration.
 *
 * To load configuration use the loadConfiguration() method.
 * e.g. in index.php
 * 
 * $dir = dirname(__FILE__) . '/protected/config/environments';
 * $config = ConfigLoader::loadConfiguration($dir, array('default', 'web', 'test'));
 * Yii::createWebApplication($config)->run();
 * 
 * The ConfigLoader::loadConfiguration() also receive file path and array.
 * e.g.
 * 
 * $dir = dirname(__FILE__) . '/protected/config/environments';
 * $config = ConfigLoader::loadConfiguration($dir, array('default', 'web', 'test', '/usr/local/share/production.php', array('language' => 'en')));
 * Yii::createWebApplication($config)->run();
 * 
 * Since this will load a lot of files, the config can be merged for production 
 * using the config command
 * 
 * $yiic config build --directory=protected/config/environments 
 *   --config=default --config=web --config=production
 *   --config=/user/local/share/production.php > protected/config/production.php
 * 
 * @author Petra Barus <petra.barus@gmail.com>
 * @package application.components
 * @since 2013.02.15
 */
class ConfigLoader
{

    /**
     * Load configuration from a directory.
     * 
     * This load configuration hierarchical. The second parameters can contain 
     * two types: array and string. If it's array then load the configuration 
     * from the array. If it's string then load the configuration from the 
     * directory named by the string. The config will be loaded from the first 
     * loaded element, and the last will override the first.
     * 
     * @param string $configdir the configuration directory.
     * @param array $configs array of configurations.
     * @return array array of configuration.
     * @since 2013.02.15
     */
    public static function loadConfiguration($configdir, $configs = array())
    {
        //$configs = array_merge(array('default'), $configs);
        $configuration = new CMap();
        foreach ($configs as $config) {
            if (is_array($config)) {//additional configuration
                $configuration->mergeWith($config);
            } else if (is_file($config)) {//if the configuration is already a file.
                $configuration->mergeWith(require_once($config));
            } else if (is_string($config)) {//this is a path name
                $configuration->mergeWith(self::loadConfigurationFiles($configdir, $config));
            }
        }
        return $configuration->toArray();
    }

    /**
     * Load configuration from files.
     * 
     * This will load hierarchical configuration files. Since the files are
     * sorted by alphabet, never use a conflicted config in one directory.
     * 
     * @param string $basedir the base directory containing environments of the
     * configurations.
     * @param string $name the sub name of the configurations.
     * @return \CMap
     */
    private static function loadConfigurationFiles($basedir, $name)
    {
        $configuration = new CMap();
        if (file_exists($basedir)) {
            $dir = $basedir . DIRECTORY_SEPARATOR . $name;
            if (is_file($application = $dir . DIRECTORY_SEPARATOR . 'application.php')) {
                $configuration->mergeWith(require_once($application));
            }
            $dir .= DIRECTORY_SEPARATOR . 'application';
            if (is_dir($dir)) {
                $files = CFileHelper::findFiles($dir, array('fileTypes' => array('php')));
                foreach ($files as $file) {
                    $path = str_replace($dir, '', $file);
                    $pathArray = explode(DIRECTORY_SEPARATOR, $path);
                    $subconfig = array();
                    $curconfig = &$subconfig; //pointing while iterating
                    for ($i = 0; $i < count($pathArray); $i++) {
                        $segment = trim($pathArray[$i]);
                        if (!empty($segment)) {
                            if ($i == count($pathArray) - 1) { //the end of segment, which is the filename
                                $segment = str_replace('.php', '', $segment);
                                $curconfig[$segment] = require_once($file);
                            } else {
                                $curconfig[$segment] = array();
                                //descent to sub config
                                $curconfig = &$curconfig[$segment];
                            }
                        }
                    }
                    if (is_array($subconfig)) {
                        $configuration->mergeWith($subconfig);
                    }
                }
            }
        }
        return $configuration;
    }

}