include/lib/KLogger.php
<?php
/**
* Finally, a light, permissions-checking logging class.
*
* Originally written for use with wpSearch
*
* Usage:
* $log = new KLogger('/var/log/', KLogger::INFO);
* $log->logInfo('Returned a million search results'); //Prints to the log file
* $log->logFatal('Oh dear.'); //Prints to the log file
* $log->logDebug('x = 5'); //Prints nothing due to current severity threshhold
*
* @author Kenny Katzgrau <katzgrau@gmail.com>
* @since July 26, 2008 — Last update July 1, 2012
* @link http://codefury.net
* @version 0.2.0
*/
/**
* Class documentation
*/
class KLogger
{
/**
* Error severity, from low to high. From BSD syslog RFC, secion 4.1.1
* @link http://www.faqs.org/rfcs/rfc3164.html
*/
const EMERG = 0; // Emergency: system is unusable
const ALERT = 1; // Alert: action must be taken immediately
const CRIT = 2; // Critical: critical conditions
const ERR = 3; // Error: error conditions
const WARN = 4; // Warning: warning conditions
const NOTICE = 5; // Notice: normal but significant condition
const INFO = 6; // Informational: informational messages
const DEBUG = 7; // Debug: debug messages
//custom logging level
/**
* Log nothing at all
*/
const OFF = 8;
/**
* Alias for CRIT
* @deprecated
*/
const FATAL = 2;
/**
* Internal status codes
*/
const STATUS_LOG_OPEN = 1;
const STATUS_OPEN_FAILED = 2;
const STATUS_LOG_CLOSED = 3;
/**
* We need a default argument value in order to add the ability to easily
* print out objects etc. But we can't use NULL, 0, FALSE, etc, because those
* are often the values the developers will test for. So we'll make one up.
*/
const NO_ARGUMENTS = 'KLogger::NO_ARGUMENTS';
/**
* Current status of the log file
* @var integer
*/
private $_logStatus = self::STATUS_LOG_CLOSED;
/**
* Holds messages generated by the class
* @var array
*/
private $_messageQueue = array();
/**
* Path to the log file
* @var string
*/
private $_logFilePath = null;
/**
* Current minimum logging threshold
* @var integer
*/
private $_severityThreshold = self::INFO;
/**
* This holds the file handle for this instance's log file
* @var resource
*/
private $_fileHandle = null;
/**
* Standard messages produced by the class. Can be modified for il8n
* @var array
*/
private $_messages = array(
//'writefail' => 'The file exists, but could not be opened for writing. Check that appropriate permissions have been set.',
'writefail' => 'The file could not be written to. Check that appropriate permissions have been set.',
'opensuccess' => 'The log file was opened successfully.',
'openfail' => 'The file could not be opened. Check permissions.',
);
/**
* Default severity of log messages, if not specified
* @var integer
*/
private static $_defaultSeverity = self::DEBUG;
/**
* Valid PHP date() format string for log timestamps
* @var string
*/
private static $_dateFormat = 'Y-m-d G:i:s';
/**
* Octal notation for default permissions of the log file
* @var integer
*/
private static $_defaultPermissions = 0777;
/**
* Array of KLogger instances, part of Singleton pattern
* @var array
*/
private static $instances = array();
/**
* Partially implements the Singleton pattern. Each $logDirectory gets one
* instance.
*
* @param string $logDirectory File path to the logging directory
* @param integer $severity One of the pre-defined severity constants
* @return KLogger
*/
public static function instance($logDirectory = false, $severity = false)
{
if ($severity === false) {
$severity = self::$_defaultSeverity;
}
if ($logDirectory === false) {
if (count(self::$instances) > 0) {
return current(self::$instances);
} else {
$logDirectory = dirname(__FILE__);
}
}
if (in_array($logDirectory, self::$instances)) {
return self::$instances[$logDirectory];
}
self::$instances[$logDirectory] = new self($logDirectory, $severity);
return self::$instances[$logDirectory];
}
/**
* Class constructor
*
* @param string $logDirectory File path to the logging directory
* @param integer $severity One of the pre-defined severity constants
* @return void
*/
public function __construct($logDirectory, $severity)
{
$logDirectory = rtrim($logDirectory, '\\/');
if ($severity === self::OFF) {
return;
}
$this->_logFilePath = $logDirectory
. DIRECTORY_SEPARATOR
. 'log_'
. date('Y-m-d')
. '.txt';
$this->_severityThreshold = $severity;
if (!file_exists($logDirectory)) {
mkdir($logDirectory, self::$_defaultPermissions, true);
}
if (file_exists($this->_logFilePath) && !is_writable($this->_logFilePath)) {
$this->_logStatus = self::STATUS_OPEN_FAILED;
$this->_messageQueue[] = $this->_messages['writefail'];
return;
}
if (($this->_fileHandle = fopen($this->_logFilePath, 'a'))) {
$this->_logStatus = self::STATUS_LOG_OPEN;
$this->_messageQueue[] = $this->_messages['opensuccess'];
} else {
$this->_logStatus = self::STATUS_OPEN_FAILED;
$this->_messageQueue[] = $this->_messages['openfail'];
}
}
/**
* Class destructor
*/
public function __destruct()
{
if ($this->_fileHandle) {
fclose($this->_fileHandle);
}
}
/**
* Writes a $line to the log with a severity level of DEBUG
*
* @param string $line Information to log
* @return void
*/
public function logDebug($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::DEBUG);
}
/**
* Returns (and removes) the last message from the queue.
* @return string
*/
public function getMessage()
{
return array_pop($this->_messageQueue);
}
/**
* Returns the entire message queue (leaving it intact)
* @return array
*/
public function getMessages()
{
return $this->_messageQueue;
}
/**
* Empties the message queue
* @return void
*/
public function clearMessages()
{
$this->_messageQueue = array();
}
/**
* Sets the date format used by all instances of KLogger
*
* @param string $dateFormat Valid format string for date()
*/
public static function setDateFormat($dateFormat)
{
self::$_dateFormat = $dateFormat;
}
/**
* Writes a $line to the log with a severity level of INFO. Any information
* can be used here, or it could be used with E_STRICT errors
*
* @param string $line Information to log
* @return void
*/
public function logInfo($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::INFO, $args);
}
/**
* Writes a $line to the log with a severity level of NOTICE. Generally
* corresponds to E_STRICT, E_NOTICE, or E_USER_NOTICE errors
*
* @param string $line Information to log
* @return void
*/
public function logNotice($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::NOTICE, $args);
}
/**
* Writes a $line to the log with a severity level of WARN. Generally
* corresponds to E_WARNING, E_USER_WARNING, E_CORE_WARNING, or
* E_COMPILE_WARNING
*
* @param string $line Information to log
* @return void
*/
public function logWarn($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::WARN, $args);
}
/**
* Writes a $line to the log with a severity level of ERR. Most likely used
* with E_RECOVERABLE_ERROR
*
* @param string $line Information to log
* @return void
*/
public function logError($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::ERR, $args);
}
/**
* Writes a $line to the log with a severity level of FATAL. Generally
* corresponds to E_ERROR, E_USER_ERROR, E_CORE_ERROR, or E_COMPILE_ERROR
*
* @param string $line Information to log
* @return void
* @deprecated Use logCrit
*/
public function logFatal($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::FATAL, $args);
}
/**
* Writes a $line to the log with a severity level of ALERT.
*
* @param string $line Information to log
* @return void
*/
public function logAlert($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::ALERT, $args);
}
/**
* Writes a $line to the log with a severity level of CRIT.
*
* @param string $line Information to log
* @return void
*/
public function logCrit($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::CRIT, $args);
}
/**
* Writes a $line to the log with a severity level of EMERG.
*
* @param string $line Information to log
* @return void
*/
public function logEmerg($line, $args = self::NO_ARGUMENTS)
{
$this->log($line, self::EMERG, $args);
}
/**
* Writes a $line to the log with the given severity
*
* @param string $line Text to add to the log
* @param integer $severity Severity level of log message (use constants)
*/
public function log($line, $severity, $args = self::NO_ARGUMENTS)
{
if ($this->_severityThreshold >= $severity) {
$status = $this->_getTimeLine($severity);
$line = "$status $line";
if($args !== self::NO_ARGUMENTS) {
/* Print the passed object value */
$line = $line . '; ' . var_export($args, true);
}
$this->writeFreeFormLine($line . PHP_EOL);
}
}
/**
* Writes a line to the log without prepending a status or timestamp
*
* @param string $line Line to write to the log
* @return void
*/
public function writeFreeFormLine($line)
{
if ($this->_logStatus == self::STATUS_LOG_OPEN
&& $this->_severityThreshold != self::OFF) {
if (fwrite($this->_fileHandle, $line) === false) {
$this->_messageQueue[] = $this->_messages['writefail'];
}
}
}
private function _getTimeLine($level)
{
$time = date(self::$_dateFormat);
switch ($level) {
case self::EMERG:
return "$time - EMERG -->";
case self::ALERT:
return "$time - ALERT -->";
case self::CRIT:
return "$time - CRIT -->";
case self::FATAL: # FATAL is an alias of CRIT
return "$time - FATAL -->";
case self::NOTICE:
return "$time - NOTICE -->";
case self::INFO:
return "$time - INFO -->";
case self::WARN:
return "$time - WARN -->";
case self::DEBUG:
return "$time - DEBUG -->";
case self::ERR:
return "$time - ERROR -->";
default:
return "$time - LOG -->";
}
}
}