<?php
/*
* Copyright 2014 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
if (!class_exists('Google_Client')) {
require_once dirname(__FILE__) . '/../autoload.php';
}
/**
* Abstract logging class based on the PSR-3 standard.
*
* NOTE: We don't implement `Psr\Log\LoggerInterface` because we need to
* maintain PHP 5.2 support.
*
* @see https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-3-logger-interface.md
*/
abstract class Google_Logger_Abstract
{
/**
* Default log format
*/
const DEFAULT_LOG_FORMAT = "[%datetime%] %level%: %message% %context%\n";
/**
* Default date format
*
* Example: 16/Nov/2014:03:26:16 -0500
*/
const DEFAULT_DATE_FORMAT = 'd/M/Y:H:i:s O';
/**
* System is unusable
*/
const EMERGENCY = 'emergency';
/**
* Action must be taken immediately
*
* Example: Entire website down, database unavailable, etc. This should
* trigger the SMS alerts and wake you up.
*/
const ALERT = 'alert';
/**
* Critical conditions
*
* Example: Application component unavailable, unexpected exception.
*/
const CRITICAL = 'critical';
/**
* Runtime errors that do not require immediate action but should typically
* be logged and monitored.
*/
const ERROR = 'error';
/**
* Exceptional occurrences that are not errors.
*
* Example: Use of deprecated APIs, poor use of an API, undesirable things
* that are not necessarily wrong.
*/
const WARNING = 'warning';
/**
* Normal but significant events.
*/
const NOTICE = 'notice';
/**
* Interesting events.
*
* Example: User logs in, SQL logs.
*/
const INFO = 'info';
/**
* Detailed debug information.
*/
const DEBUG = 'debug';
/**
* @var array $levels Logging levels
*/
protected static $levels = array(
self::EMERGENCY => 600,
self::ALERT => 550,
self::CRITICAL => 500,
self::ERROR => 400,
self::WARNING => 300,
self::NOTICE => 250,
self::INFO => 200,
self::DEBUG => 100,
);
/**
* @var integer $level The minimum logging level
*/
protected $level = self::DEBUG;
/**
* @var string $logFormat The current log format
*/
protected $logFormat = self::DEFAULT_LOG_FORMAT;
/**
* @var string $dateFormat The current date format
*/
protected $dateFormat = self::DEFAULT_DATE_FORMAT;
/**
* @var boolean $allowNewLines If newlines are allowed
*/
protected $allowNewLines = false;
/**
* @param Google_Client $client The current Google client
*/
public function __construct(Google_Client $client)
{
$this->setLevel(
$client->getClassConfig('Google_Logger_Abstract', 'level')
);
$format = $client->getClassConfig('Google_Logger_Abstract', 'log_format');
$this->logFormat = $format ? $format : self::DEFAULT_LOG_FORMAT;
$format = $client->getClassConfig('Google_Logger_Abstract', 'date_format');
$this->dateFormat = $format ? $format : self::DEFAULT_DATE_FORMAT;
$this->allowNewLines = (bool) $client->getClassConfig(
'Google_Logger_Abstract',
'allow_newlines'
);
}
/**
* Sets the minimum logging level that this logger handles.
*
* @param integer $level
*/
public function setLevel($level)
{
$this->level = $this->normalizeLevel($level);
}
/**
* Checks if the logger should handle messages at the provided level.
*
* @param integer $level
* @return boolean
*/
public function shouldHandle($level)
{
return $this->normalizeLevel($level) >= $this->level;
}
/**
* System is unusable.
*
* @param string $message The log message
* @param array $context The log context
*/
public function emergency($message, array $context = array())
{
$this->log(self::EMERGENCY, $message, $context);
}
/**
* Action must be taken immediately.
*
* Example: Entire website down, database unavailable, etc. This should
* trigger the SMS alerts and wake you up.
*
* @param string $message The log message
* @param array $context The log context
*/
public function alert($message, array $context = array())
{
$this->log(self::ALERT, $message, $context);
}
/**
* Critical conditions.
*
* Example: Application component unavailable, unexpected exception.
*
* @param string $message The log message
* @param array $context The log context
*/
public function critical($message, array $context = array())
{
$this->log(self::CRITICAL, $message, $context);
}
/**
* Runtime errors that do not require immediate action but should typically
* be logged and monitored.
*
* @param string $message The log message
* @param array $context The log context
*/
public function error($message, array $context = array())
{
$this->log(self::ERROR, $message, $context);
}
/**
* Exceptional occurrences that are not errors.
*
* Example: Use of deprecated APIs, poor use of an API, undesirable things
* that are not necessarily wrong.
*
* @param string $message The log message
* @param array $context The log context
*/
public function warning($message, array $context = array())
{
$this->log(self::WARNING, $message, $context);
}
/**
* Normal but significant events.
*
* @param string $message The log message
* @param array $context The log context
*/
public function notice($message, array $context = array())
{
$this->log(self::NOTICE, $message, $context);
}
/**
* Interesting events.
*
* Example: User logs in, SQL logs.
*
* @param string $message The log message
* @param array $context The log context
*/
public function info($message, array $context = array())
{
$this->log(self::INFO, $message, $context);
}
/**
* Detailed debug information.
*
* @param string $message The log message
* @param array $context The log context
*/
public function debug($message, array $context = array())
{
$this->log(self::DEBUG, $message, $context);
}
/**
* Logs with an arbitrary level.
*
* @param mixed $level The log level
* @param string $message The log message
* @param array $context The log context
*/
public function log($level, $message, array $context = array())
{
if (!$this->shouldHandle($level)) {
return false;
}
$levelName = is_int($level) ? array_search($level, self::$levels) : $level;
$message = $this->interpolate(
array(
'message' => $message,
'context' => $context,
'level' => strtoupper($levelName),
'datetime' => new DateTime(),
)
);
$this->write($message);
}
/**
* Interpolates log variables into the defined log format.
*
* @param array $variables The log variables.
* @return string
*/
protected function interpolate(array $variables = array())
{
$template = $this->logFormat;
if (!$variables['context']) {
$template = str_replace('%context%', '', $template);
unset($variables['context']);
} else {
$this->reverseJsonInContext($variables['context']);
}
foreach ($variables as $key => $value) {
if (strpos($template, '%'. $key .'%') !== false) {
$template = str_replace(
'%' . $key . '%',
$this->export($value),
$template
);
}
}
return $template;
}
/**
* Reverses JSON encoded PHP arrays and objects so that they log better.
*
* @param array $context The log context
*/
protected function reverseJsonInContext(array &$context)
{
if (!$context) {
return;
}
foreach ($context as $key => $val) {
if (!$val || !is_string($val) || !($val[0] == '{' || $val[0] == '[')) {
continue;
}
$json = @json_decode($val);
if (is_object($json) || is_array($json)) {
$context[$key] = $json;
}
}
}
/**
* Exports a PHP value for logging to a string.
*
* @param mixed $value The value to
*/
protected function export($value)
{
if (is_string($value)) {
if ($this->allowNewLines) {
return $value;
}
return preg_replace('/[\r\n]+/', ' ', $value);
}
if (is_resource($value)) {
return sprintf(
'resource(%d) of type (%s)',
$value,
get_resource_type($value)
);
}
if ($value instanceof DateTime) {
return $value->format($this->dateFormat);
}
if (version_compare(PHP_VERSION, '5.4.0', '>=')) {
$options = JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE;
if ($this->allowNewLines) {
$options |= JSON_PRETTY_PRINT;
}
return @json_encode($value, $options);
}
return str_replace('\\/', '/', @json_encode($value));
}
/**
* Converts a given log level to the integer form.
*
* @param mixed $level The logging level
* @return integer $level The normalized level
* @throws Google_Logger_Exception If $level is invalid
*/
protected function normalizeLevel($level)
{
if (is_int($level) && array_search($level, self::$levels) !== false) {
return $level;
}
if (is_string($level) && isset(self::$levels[$level])) {
return self::$levels[$level];
}
throw new Google_Logger_Exception(
sprintf("Unknown LogLevel: '%s'", $level)
);
}
/**
* Writes a message to the current log implementation.
*
* @param string $message The message
*/
abstract protected function write($message);
}