php工具类之【自定义日志记录类】

<?php
if(!defined("DIR_ROOT")){
	define("DIR_ROOT", dirname(dirname(__FILE__)));
}
define('LEVEL_FATAL', 0);
define('LEVEL_ERROR', 1);
define('LEVEL_WARN', 2);
define('LEVEL_INFO', 3);
define('LEVEL_DEBUG', 4);
/**
 * 记录操作过程中的日志信息
 * @version 1.0 20140725
 */
class Logger {
    static $LOG_LEVEL_NAMES = array(
        'FATAL', 'ERROR', 'WARN', 'INFO', 'DEBUG'
    );

    private $level = LEVEL_DEBUG;
    private $rootDir = DIR_ROOT;

    static function getInstance() {
        return new Logger;
    }
    /**
     * 设置最小的log记录级别，小于该级别的log日志输出将被忽略掉
     * @param int $lvl -- 最小的log日志输出级别
     * @throws Exception
     */
    function setLogLevel($lvl) {
        if($lvl >= count(Logger::$LOG_LEVEL_NAMES)  || $lvl < 0) {
            throw new Exception('invalid log level:' . $lvl);
        }
        $this->level = $lvl;
    }
    //###################输出各个级别的日志信息---start==============
    function debug($message, $name = 'root') {
        $this->_log(LEVEL_DEBUG, $message, $name);
    }
    function info($message, $name = 'root') {
        $this->_log(LEVEL_INFO, $message, $name);
    }
    function warn($message, $name = 'root') {
        $this->_log(LEVEL_WARN, $message, $name);
    }
    function error($message, $name = 'root') {
        $this->_log(LEVEL_ERROR, $message, $name);
    }
    function fatal($message, $name = 'root') {
        $this->_log(LEVEL_FATAL, $message, $name);
    }
    //###################输出各个级别的日志信息---end==============
 	/**
 	 * 记录log日志信息
 	 * @param unknown_type $level
 	 * @param unknown_type $message
 	 * @param unknown_type $name
 	 */
 	private function _log($level, $message, $name) {
        if($level > $this->level) {
            return;
        }
    
        $log_file_path = $this->rootDir."/logs/".$name.'.log';
        $log_level_name = Logger::$LOG_LEVEL_NAMES[$this->level];
        $content = date('Y-m-d H:i:s') . ' [' . $log_level_name . '] ' . $message . "\n";
        file_put_contents($log_file_path, $content, FILE_APPEND);
    }
}
//
//$logger = Logger::getInstance();
//$logger->debug('this is my first log', 'test');