Custom Logging Threshold - bcit-ci/CodeIgniter GitHub Wiki
Extends the functionality of the CI_Log class by allowing users to choose which threshold levels they want to log, rather than logging all the way up to the given threshold value.
Usage
Create a file named Log.php in application/libraries/ and paste the script below into it:
<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package  CodeIgniter
 * @author  ExpressionEngine Dev Team
 * @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license  http://codeigniter.com/user_guide/license.html
 * @link  http://codeigniter.com
 * @since  Version 1.0
 * @filesource
 */
// ------------------------------------------------------------------------
/**
 * Logging Class
 *
 * @package  CodeIgniter
 * @subpackage Libraries
 * @category Logging
 * @author  ExpressionEngine Dev Team
 * @link  http://codeigniter.com/user_guide/general/errors.html
 */
 
// ------------------------------------------------------------------------
/**
 * Custom Logging Threshold
 *
 * Extends the functionality of the CI_Log class by allowing users to choose which
 * threshold level(s) they want to log, rather than logging all the way up to the
 * given threshold.
 *
 * @package  CodeIgniter
 * @subpackage Libraries
 * @category Logging
 * @author  Matthew Switzer (StrayIdeas)
 * @link  http://codeigniter.com/wiki/Custom_Logging_Threshold/
 */
class CI_Log {
 protected $_log_path;
 protected $_threshold = 1;
 protected $_date_fmt = 'Y-m-d H:i:s';
 protected $_enabled = TRUE;
 protected $_levels = array('ERROR' => '1', 'DEBUG' => '2',  'INFO' => '3', 'ALL' => '4');
 /**
  * Constructor
  */
 public function __construct()
 {
  $config =& get_config();
  $this->_log_path = ($config['log_path'] != '') ? $config['log_path'] : APPPATH.'logs/';
  if ( ! is_dir($this->_log_path) OR ! is_really_writable($this->_log_path))
  {
   $this->_enabled = FALSE;
  }
        // also allow threshold values to be passed as an array
  if (is_numeric($config['log_threshold']) OR is_array($config['log_threshold']))
  {
   $this->_threshold = $config['log_threshold'];
  }
  if ($config['log_date_format'] != '')
  {
   $this->_date_fmt = $config['log_date_format'];
  }
 }
 // --------------------------------------------------------------------
 /**
  * Write Log File
  *
  * Generally this function will be called using the global log_message() function
  *
  * @param string the error level
  * @param string the error message
  * @param bool whether the error is a native PHP error
  * @return bool
  */
 public function write_log($level = 'error', $msg, $php_error = FALSE)
 {
  if ($this->_enabled === FALSE)
  {
   return FALSE;
  }
  $level = strtoupper($level);
  if ( ! isset($this->_levels[$level])
  OR ($this->_levels[$level] > $this->_threshold)
        // if the threshold values is an array, check to see if the error level does not exist in it
  OR (is_array($this->_threshold) && ! in_array($this->_levels[$level], $this->_threshold)))
  {
   return FALSE;
  }
  $filepath = $this->_log_path.'log-'.date('Y-m-d').'.php';
  $message  = '';
  if ( ! file_exists($filepath))
  {
   $message .= "<"."?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed'); ?".">\n\n";
  }
  if ( ! $fp = @fopen($filepath, FOPEN_WRITE_CREATE) )
  {
   return FALSE;
  }
  $message .= $level.' '.(($level == 'INFO') ? ' -' : '-').' '.date($this->_date_fmt). ' --> '.$msg."\n";
  flock($fp, LOCK_EX);
  fwrite($fp, $message);
  flock($fp, LOCK_UN);
  fclose($fp);
  @chmod($filepath, FILE_WRITE_MODE);
  return TRUE;
 }
}
// END Log Class
/* End of file Log.php */
/* Location: ./application/libraries/Log.php */
Next, open config.php and edit the value of the $config['log_threshold'] variable:
// pass an array containing the threshold values you want to log
$config['log_threshold'] = array(1, 3);
// this will log only informational messages
$config['log_threshold'] = array(3);
Note: If you wish to retain the original functionality of the $config['log_threshold'] variable, simply pass an integer as the value:
$config['log_threshold'] = 3;