Extend PDO to connect via an object, array, or ini file. Adds methods to backup/restore database

pdo_connect.php

<?php
	/**
	 * Wrapper for standard PDO class.
	 *
	 * This class is meant only to be extended and
	 * not used directly. It offers only a protected
	 * __construct method and a public escape.
	 *
	 * @author Chris Zuber <shgysk8zer0@gmail.com>
	 * @copyright 2014, Chris Zuber
	 * @license http://opensource.org/licenses/GPL-3.0 GNU General Public License, version 3 (GPL-3.0)
	 * @package core_shared
	 * @version 2014-08-27
	*/

	class pdo_connect extends PDO {
		private $connect;
		private static $instances = [];
		public $connected;

		public function load($con = 'connect') {
			/**
			 * Static class load method
			 *
			 * Creates a new instance and returns it if one does not exist,
			 * otherwise returns the existing instance
			 *
			 * @param mixed $con
			 * @return pdo_connect
			 */

			if(!array_key_exists($con, self::$instances)) {
				self::$instances[$con] = new self($con);
			}
			return self::$instances[$con];
		}

		public function __construct($con = 'connect') {
			/**
			 * @method __construct
			 * @desc
			 * Gets database connection info from /connect.ini (using parse_ini_file)
			 * The default ini file to use is connect, but can be passed another
			 * in the $con argument.
			 *
			 * Uses that data to create a new PHP Data Object
			 *
			 * @param mixed $con (.ini file to use for database credentials)
			 * @return void
			 * @example parent::__construct($con)
			 */


			$this->connected = false;

			if(is_string($con)) {
				$this->connect = (object)parse_ini_file("{$con}.ini");
			}
			elseif(is_object($con)) {
				$this->connect = $con;
			}
			elseif(is_array($con)) {
				$this->connect = (object)$con;
			}

			try{
				if(!(isset($this->connect->user) and isset($this->connect->password))) throw new Exception('Missing credentials to connect to database');
				$connect_string = (isset($this->connect->type)) ? "{$this->connect->type}:" : 'mysql:';
				$connect_string .= (isset($this->connect->database)) ?  "dbname={$this->connect->database}" : "dbname={$this->connect->user}";
				if(isset($this->connect->server)) $connect_string .= ";host={$this->connect->server}";
				if(isset($this->connect->port) and $this->connect->server !== 'localhost') $connect_string .= ";port={$this->connect->port}";
				parent::__construct($connect_string, $this->connect->user, $this->connect->password);
				$this->connected = true;
			}
			catch(Exception $e) {
				if(!isset($connect_string)) {
					$connect_string = 'Connect String not set';
				}
				$this->log(__METHOD__, __LINE__, $connect_string . PHP_EOL . $e->getMessage());
			}
		}

		private function log($method = null, $line = null, $message = '') {
			/**
			 * Writes errors to a log file
			 *
			 * @param string $method
			 * @param int $line
			 * @param string $message
			 * @return void
			 */

			file_put_contents(BASE . '/' . __CLASS__ . '.log', "Error in $method in line $line: $message" . PHP_EOL, FILE_APPEND | LOCK_EX);
		}

		public function restore($fname = null) {
			/**
			 * Restores a MySQL database from file $fname
			 *
			 * @param string $fname
			 * @return self
			 */

			if(is_null($fname)) {
				$fname = BASE . DIRECTORY_SEPERATOR . $this->connect->database;
			}

			$sql = file_get_contents("{$fname}.sql");
			if(is_string($sql)) {
				return $this->query($sql);
			}
			else {
				return false;
			}
		}

		public function dump($filename = null) {
			/**
			 * Does a mysqldump if permissions allow
			 *
			 * Return value is based on whether or not permissions
			 * allow file to be written, not whether or not it was.
			 *
			 * Default filename is the name of the database
			 * from connection
			 *
			 * @param string $filename
			 * @return boolean
			 */

			if(is_null($filename)) {
				$filename = BASE . '/' . $this->connect->database;
			}

			if((file_exists("{$filename}.sql") and is_writable("{$filename}.sql")) or (!file_exists("{$filename}.sql") and is_writable(BASE))) {
				$command = "mysqldump -u {$this->connect->user} -p" . escapeshellcmd($this->connect->password);

				if(isset($this->connect->server) and $this->connect->server !== 'localhost') {
					$command .= " -h {$this->connect->server}";
				}

				$command .= " {$this->connect->database} > {$filename}.sql";

				exec($command);
				return true;
			}
			else {
				return false;
			}
		}
	}
?>