includes/debug/logger/LegacyLogger.php
<?php
/**
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
namespace MediaWiki\Logger;
use DateTimeZone;
use Error;
use LogicException;
use MediaWiki\Debug\MWDebug;
use MediaWiki\WikiMap\WikiMap;
use MWExceptionHandler;
use Psr\Log\AbstractLogger;
use Psr\Log\LogLevel;
use Throwable;
use UDPTransport;
use Wikimedia\AtEase\AtEase;
/**
* PSR-3 logger that mimics the historic implementation of MediaWiki's former
* wfErrorLog logging implementation.
*
* This logger is configured by the following global configuration variables:
* - `$wgDebugLogFile`
* - `$wgDebugLogGroups`
* - `$wgDBerrorLog`
* - `$wgDBerrorLogTZ`
*
* See docs/Configuration.md for detailed explanations of these settings.
*
* @see \MediaWiki\Logger\LoggerFactory
* @since 1.25
* @ingroup Debug
* @copyright © 2014 Wikimedia Foundation and contributors
*/
class LegacyLogger extends AbstractLogger {
/**
* @var string
*/
protected $channel;
private const LEVEL_DEBUG = 100;
private const LEVEL_INFO = 200;
private const LEVEL_NOTICE = 250;
private const LEVEL_WARNING = 300;
private const LEVEL_ERROR = 400;
private const LEVEL_CRITICAL = 500;
private const LEVEL_ALERT = 550;
private const LEVEL_EMERGENCY = 600;
private const LEVEL_INFINITY = 999;
/**
* Convert \Psr\Log\LogLevel constants into int for sensible comparisons
* These are the same values that Monolog uses
*
* @var array
*/
protected static $levelMapping = [
LogLevel::DEBUG => self::LEVEL_DEBUG,
LogLevel::INFO => self::LEVEL_INFO,
LogLevel::NOTICE => self::LEVEL_NOTICE,
LogLevel::WARNING => self::LEVEL_WARNING,
LogLevel::ERROR => self::LEVEL_ERROR,
LogLevel::CRITICAL => self::LEVEL_CRITICAL,
LogLevel::ALERT => self::LEVEL_ALERT,
LogLevel::EMERGENCY => self::LEVEL_EMERGENCY,
];
/**
* Minimum level. This is just to allow faster discard of debugging
* messages. Not all messages meeting the level will be logged.
*
* @var int
*/
private $minimumLevel;
/**
* Whether the channel is a DB channel
*
* @var bool
*/
private $isDB;
/**
* @param string $channel
*/
public function __construct( $channel ) {
global $wgDebugLogFile, $wgDBerrorLog, $wgDebugLogGroups, $wgDebugToolbar, $wgDebugRawPage, $wgShowDebug;
$this->channel = $channel;
$this->isDB = ( $channel === 'rdbms' );
// Calculate minimum level, duplicating some of the logic from log() and shouldEmit()
if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
$this->minimumLevel = self::LEVEL_WARNING;
} elseif ( $wgDebugLogFile != '' || $wgShowDebug || $wgDebugToolbar ) {
// Log all messages if there is a debug log file or debug toolbar
$this->minimumLevel = self::LEVEL_DEBUG;
} elseif ( isset( $wgDebugLogGroups[$channel] ) ) {
$logConfig = $wgDebugLogGroups[$channel];
// Log messages if the config is set, according to the configured level
if ( is_array( $logConfig ) && isset( $logConfig['level'] ) ) {
$this->minimumLevel = self::$levelMapping[$logConfig['level']];
} else {
$this->minimumLevel = self::LEVEL_DEBUG;
}
} else {
// No other case hit: discard all messages
$this->minimumLevel = self::LEVEL_INFINITY;
}
if ( $this->isDB && $wgDBerrorLog && $this->minimumLevel > self::LEVEL_ERROR ) {
// Log DB errors if there is a DB error log
$this->minimumLevel = self::LEVEL_ERROR;
}
}
/**
* Change an existing Logger singleton to act like NullLogger.
*
* @internal For use by MediaWikiIntegrationTestCase::setNullLogger
* @param null|int $level
* @return int
*/
public function setMinimumForTest( ?int $level ) {
if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
throw new LogicException( 'Not allowed outside tests' );
}
// Set LEVEL_INFINITY if given null, or restore the original level.
$original = $this->minimumLevel;
$this->minimumLevel = $level ?? self::LEVEL_INFINITY;
return $original;
}
/**
* Logs with an arbitrary level.
*
* @param string|int $level
* @param string $message
* @param array $context
*/
public function log( $level, $message, array $context = [] ) {
if ( is_string( $level ) ) {
$level = self::$levelMapping[$level];
}
if ( $level < $this->minimumLevel ) {
return;
}
if ( $this->isDB
&& $level === self::LEVEL_DEBUG
&& isset( $context['sql'] )
) {
// Also give the query information to the MWDebug tools
MWDebug::query(
$context['sql'],
$context['method'],
$context['runtime_ms'] / 1000,
$context['db_server']
);
}
// If this is a DB-related error, and the site has $wgDBerrorLog
// configured, rewrite the channel as wfLogDBError instead.
// Likewise, if the site does not use $wgDBerrorLog, it should
// configurable like any other channel via $wgDebugLogGroups
// or $wgMWLoggerDefaultSpi.
global $wgDBerrorLog;
if ( $this->isDB && $level >= self::LEVEL_ERROR && $wgDBerrorLog ) {
// Format and write DB errors to the legacy locations
$effectiveChannel = 'wfLogDBError';
} else {
$effectiveChannel = $this->channel;
}
if ( self::shouldEmit( $effectiveChannel, $message, $level, $context ) ) {
$text = self::format( $effectiveChannel, $message, $context );
$destination = self::destination( $effectiveChannel, $message, $context );
$this->maybeLogToStderr( $text );
self::emit( $text, $destination );
}
if ( !isset( $context['private'] ) || !$context['private'] ) {
// Add to debug toolbar if not marked as "private"
MWDebug::debugMsg( $message, [ 'channel' => $this->channel ] + $context );
}
}
/**
* Determine if the given message should be emitted or not.
*
* @param string $channel
* @param string $message
* @param string|int $level \Psr\Log\LogEvent constant or Monolog level int
* @param array $context
* @return bool True if message should be sent to disk/network, false
* otherwise
*/
public static function shouldEmit( $channel, $message, $level, $context ) {
global $wgDebugLogFile, $wgDBerrorLog, $wgDebugLogGroups;
if ( is_string( $level ) ) {
$level = self::$levelMapping[$level];
}
if ( $channel === 'wfLogDBError' ) {
// wfLogDBError messages are emitted if a database log location is
// specified.
$shouldEmit = (bool)$wgDBerrorLog;
} elseif ( $channel === 'wfDebug' ) {
// wfDebug messages are emitted if a catch all logging file has
// been specified. Checked explicitly so that 'private' flagged
// messages are not discarded by unset $wgDebugLogGroups channel
// handling below.
$shouldEmit = $wgDebugLogFile != '';
} elseif ( isset( $wgDebugLogGroups[$channel] ) ) {
$logConfig = $wgDebugLogGroups[$channel];
if ( is_array( $logConfig ) ) {
$shouldEmit = true;
if ( isset( $logConfig['sample'] ) ) {
// Emit randomly with a 1 in 'sample' chance for each message.
$shouldEmit = mt_rand( 1, $logConfig['sample'] ) === 1;
}
if ( isset( $logConfig['level'] ) ) {
$shouldEmit = $level >= self::$levelMapping[$logConfig['level']];
}
} else {
// Emit unless the config value is explicitly false.
$shouldEmit = $logConfig !== false;
}
} elseif ( isset( $context['private'] ) && $context['private'] ) {
// Don't emit if the message didn't match previous checks based on
// the channel and the event is marked as private. This check
// discards messages sent via wfDebugLog() with dest == 'private'
// and no explicit wgDebugLogGroups configuration.
$shouldEmit = false;
} else {
// Default return value is the same as the historic wfDebug
// method: emit if $wgDebugLogFile has been set.
$shouldEmit = $wgDebugLogFile != '';
}
return $shouldEmit;
}
/**
* Format a message.
*
* Messages to the 'wfDebug' and 'wfLogDBError' channels receive special formatting to mimic the
* historic output of the functions of the same name. All other channel values are formatted
* based on the historic output of the `wfDebugLog()` global function.
*
* @param string $channel
* @param string $message
* @param array $context
* @return string
*/
public static function format( $channel, $message, $context ) {
global $wgDebugLogGroups, $wgLogExceptionBacktrace;
if ( $channel === 'wfDebug' ) {
$text = self::formatAsWfDebug( $channel, $message, $context );
} elseif ( $channel === 'wfLogDBError' ) {
$text = self::formatAsWfLogDBError( $channel, $message, $context );
} elseif ( !isset( $wgDebugLogGroups[$channel] ) ) {
$text = self::formatAsWfDebug(
$channel, "[{$channel}] {$message}", $context );
} else {
// Default formatting is wfDebugLog's historic style
$text = self::formatAsWfDebugLog( $channel, $message, $context );
}
// Append stacktrace of throwable if available
if ( $wgLogExceptionBacktrace && isset( $context['exception'] ) ) {
$e = $context['exception'];
$backtrace = false;
if ( $e instanceof Throwable ) {
$backtrace = MWExceptionHandler::getRedactedTrace( $e );
} elseif ( is_array( $e ) && isset( $e['trace'] ) ) {
// Throwable has already been unpacked as structured data
$backtrace = $e['trace'];
}
if ( $backtrace ) {
$text .= MWExceptionHandler::prettyPrintTrace( $backtrace ) .
"\n";
}
}
return self::interpolate( $text, $context );
}
/**
* Format a message as `wfDebug()` would have formatted it.
*
* @param string $channel
* @param string $message
* @param array $context
* @return string
*/
protected static function formatAsWfDebug( $channel, $message, $context ) {
$text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $message );
if ( isset( $context['seconds_elapsed'] ) ) {
// Prepend elapsed request time and real memory usage with two
// trailing spaces.
$text = "{$context['seconds_elapsed']} {$context['memory_used']} {$text}";
}
if ( isset( $context['prefix'] ) ) {
$text = "{$context['prefix']}{$text}";
}
return "{$text}\n";
}
/**
* Format a message as `wfLogDBError()` would have formatted it.
*
* @param string $channel
* @param string $message
* @param array $context
* @return string
*/
protected static function formatAsWfLogDBError( $channel, $message, $context ) {
global $wgDBerrorLogTZ;
static $cachedTimezone = null;
if ( !$cachedTimezone ) {
$cachedTimezone = new DateTimeZone( $wgDBerrorLogTZ );
}
$d = date_create( 'now', $cachedTimezone );
$date = $d->format( 'D M j G:i:s T Y' );
$host = wfHostname();
$wiki = WikiMap::getCurrentWikiId();
$text = "{$date}\t{$host}\t{$wiki}\t{$message}\n";
return $text;
}
/**
* Format a message as `wfDebugLog() would have formatted it.
*
* @param string $channel
* @param string $message
* @param array $context
* @return string
*/
protected static function formatAsWfDebugLog( $channel, $message, $context ) {
$time = wfTimestamp( TS_DB );
$wiki = WikiMap::getCurrentWikiId();
$host = wfHostname();
$text = "{$time} {$host} {$wiki}: {$message}\n";
return $text;
}
/**
* Interpolate placeholders in logging message.
*
* @param string $message
* @param array $context
* @return string Interpolated message
*/
public static function interpolate( $message, array $context ) {
if ( str_contains( $message, '{' ) ) {
$replace = [];
foreach ( $context as $key => $val ) {
$replace['{' . $key . '}'] = self::flatten( $val );
}
$message = strtr( $message, $replace );
}
return $message;
}
/**
* Convert a logging context element to a string suitable for
* interpolation.
*
* @param mixed $item
* @return string
*/
protected static function flatten( $item ) {
if ( $item === null ) {
return '[Null]';
}
if ( is_bool( $item ) ) {
return $item ? 'true' : 'false';
}
if ( is_float( $item ) ) {
if ( is_infinite( $item ) ) {
return ( $item > 0 ? '' : '-' ) . 'INF';
}
if ( is_nan( $item ) ) {
return 'NaN';
}
return (string)$item;
}
if ( is_scalar( $item ) ) {
return (string)$item;
}
if ( is_array( $item ) ) {
return '[Array(' . count( $item ) . ')]';
}
if ( $item instanceof \DateTime ) {
return $item->format( 'c' );
}
if ( $item instanceof Throwable ) {
$which = $item instanceof Error ? 'Error' : 'Exception';
return '[' . $which . ' ' . get_class( $item ) . '( ' .
$item->getFile() . ':' . $item->getLine() . ') ' .
$item->getMessage() . ']';
}
if ( is_object( $item ) ) {
if ( method_exists( $item, '__toString' ) ) {
return (string)$item;
}
return '[Object ' . get_class( $item ) . ']';
}
// phpcs:ignore MediaWiki.Usage.ForbiddenFunctions.is_resource
if ( is_resource( $item ) ) {
return '[Resource ' . get_resource_type( $item ) . ']';
}
return '[Unknown ' . gettype( $item ) . ']';
}
/**
* Select the appropriate log output destination for the given log event.
*
* If the event context contains 'destination'
*
* @param string $channel
* @param string $message
* @param array $context
* @return string
*/
protected static function destination( $channel, $message, $context ) {
global $wgDebugLogFile, $wgDBerrorLog, $wgDebugLogGroups;
// Default destination is the debug log file as historically used by
// the wfDebug function.
$destination = $wgDebugLogFile;
if ( isset( $context['destination'] ) ) {
// Use destination explicitly provided in context
$destination = $context['destination'];
} elseif ( $channel === 'wfDebug' ) {
$destination = $wgDebugLogFile;
} elseif ( $channel === 'wfLogDBError' ) {
$destination = $wgDBerrorLog;
} elseif ( isset( $wgDebugLogGroups[$channel] ) ) {
$logConfig = $wgDebugLogGroups[$channel];
if ( is_array( $logConfig ) ) {
$destination = $logConfig['destination'];
} else {
$destination = strval( $logConfig );
}
}
return $destination;
}
/**
* Log to a file without getting "file size exceeded" signals.
*
* Can also log to UDP with the syntax udp://host:port/prefix. This will send
* lines to the specified port, prefixed by the specified prefix and a space.
*
* @param string $text
* @param string $file Filename
*/
public static function emit( $text, $file ) {
if ( str_starts_with( $file, 'udp:' ) ) {
$transport = UDPTransport::newFromString( $file );
$transport->emit( $text );
} else {
AtEase::suppressWarnings();
$exists = file_exists( $file );
$size = $exists ? filesize( $file ) : false;
if ( !$exists ||
( $size !== false && $size + strlen( $text ) < 0x7fffffff )
) {
file_put_contents( $file, $text, FILE_APPEND );
}
AtEase::restoreWarnings();
}
}
/**
* If MW_LOG_STDERR is set (used currently in `composer serve`) then also
* emit to stderr using error_log().
*
* @param string $text
* @return void
*/
private function maybeLogToStderr( string $text ): void {
if ( getenv( 'MW_LOG_STDERR' ) ) {
error_log( trim( $text ) );
}
}
}