Merge "Code style cleanup for ApiQuerySiteinfo.php."

[mediawiki.git] / includes / debug / Debug.php

<?php
/**
 * Debug toolbar related code.
 *
 * 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
 */

/**
 * New debugger system that outputs a toolbar on page view.
 *
 * By default, most methods do nothing ( self::$enabled = false ). You have
 * to explicitly call MWDebug::init() to enabled them.
 *
 * @todo Profiler support
 *
 * @since 1.19
 */
class MWDebug {

        /**
         * Log lines
         *
         * @var array $log
         */
        protected static $log = array();

        /**
         * Debug messages from wfDebug().
         *
         * @var array $debug
         */
        protected static $debug = array();

        /**
         * SQL statements of the databses queries.
         *
         * @var array $query
         */
        protected static $query = array();

        /**
         * Is the debugger enabled?
         *
         * @var bool $enabled
         */
        protected static $enabled = false;

        /**
         * Array of functions that have already been warned, formatted
         * function-caller to prevent a buttload of warnings
         *
         * @var array $deprecationWarnings
         */
        protected static $deprecationWarnings = array();

        /**
         * Enabled the debugger and load resource module.
         * This is called by Setup.php when $wgDebugToolbar is true.
         *
         * @since 1.19
         */
        public static function init() {
                self::$enabled = true;
        }

        /**
         * Add ResourceLoader modules to the OutputPage object if debugging is
         * enabled.
         *
         * @since 1.19
         * @param $out OutputPage
         */
        public static function addModules( OutputPage $out ) {
                if ( self::$enabled ) {
                        $out->addModules( 'mediawiki.debug.init' );
                }
        }

        /**
         * Adds a line to the log
         *
         * @todo Add support for passing objects
         *
         * @since 1.19
         * @param $str string
         */
        public static function log( $str ) {
                if ( !self::$enabled ) {
                        return;
                }

                self::$log[] = array(
                        'msg' => htmlspecialchars( $str ),
                        'type' => 'log',
                        'caller' => wfGetCaller(),
                );
        }

        /**
         * Returns internal log array
         * @since 1.19
         * @return array
         */
        public static function getLog() {
                return self::$log;
        }

        /**
         * Clears internal log array and deprecation tracking
         * @since 1.19
         */
        public static function clearLog() {
                self::$log = array();
                self::$deprecationWarnings = array();
        }

        /**
         * Adds a warning entry to the log
         *
         * @since 1.19
         * @param $msg string
         * @param $callerOffset int
         * @param $level int A PHP error level. See sendWarning()
         * @param $log string: 'production' will always trigger a php error, 'auto'
         *        will trigger an error if $wgDevelopmentWarnings is true, and 'debug'
         *        will only write to the debug log(s).
         *
         * @return mixed
         */
        public static function warning( $msg, $callerOffset = 1, $level = E_USER_NOTICE, $log = 'auto' ) {
                global $wgDevelopmentWarnings;

                if ( $log === 'auto' && !$wgDevelopmentWarnings ) {
                        $log = 'debug';
                }

                if ( $log === 'debug' ) {
                        $level = false;
                }

                $callerDescription = self::getCallerDescription( $callerOffset );

                self::sendWarning( $msg, $callerDescription, $level );

                if ( self::$enabled ) {
                        self::$log[] = array(
                                'msg' => htmlspecialchars( $msg ),
                                'type' => 'warn',
                                'caller' => $callerDescription['func'],
                        );
                }
        }

        /**
         * Show a warning that $function is deprecated.
         * This will send it to the following locations:
         * - Debug toolbar, with one item per function and caller, if $wgDebugToolbar
         *   is set to true.
         * - PHP's error log, with level E_USER_DEPRECATED, if $wgDevelopmentWarnings
         *   is set to true.
         * - MediaWiki's debug log, if $wgDevelopmentWarnings is set to false.
         *
         * @since 1.19
         * @param string $function Function that is deprecated.
         * @param string|bool $version Version in which the function was deprecated.
         * @param string|bool $component Component to which the function belongs.
         *     If false, it is assumbed the function is in MediaWiki core.
         * @param $callerOffset integer: How far up the callstack is the original
         *    caller. 2 = function that called the function that called
         *    MWDebug::deprecated() (Added in 1.20).
         * @return mixed
         */
        public static function deprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
                $callerDescription = self::getCallerDescription( $callerOffset );
                $callerFunc = $callerDescription['func'];

                $sendToLog = true;

                // Check to see if there already was a warning about this function
                if ( isset( self::$deprecationWarnings[$function][$callerFunc] ) ) {
                        return;
                } elseif ( isset( self::$deprecationWarnings[$function] ) ) {
                        if ( self::$enabled ) {
                                $sendToLog = false;
                        } else {
                                return;
                        }
                }

                self::$deprecationWarnings[$function][$callerFunc] = true;

                if ( $version ) {
                        global $wgDeprecationReleaseLimit;
                        if ( $wgDeprecationReleaseLimit && $component === false ) {
                                # Strip -* off the end of $version so that branches can use the
                                # format #.##-branchname to avoid issues if the branch is merged into
                                # a version of MediaWiki later than what it was branched from
                                $comparableVersion = preg_replace( '/-.*$/', '', $version );

                                # If the comparableVersion is larger than our release limit then
                                # skip the warning message for the deprecation
                                if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
                                        $sendToLog = false;
                                }
                        }

                        $component = $component === false ? 'MediaWiki' : $component;
                        $msg = "Use of $function was deprecated in $component $version.";
                } else {
                        $msg = "Use of $function is deprecated.";
                }

                if ( $sendToLog ) {
                        global $wgDevelopmentWarnings; // we could have a more specific $wgDeprecationWarnings setting.
                        self::sendWarning( $msg, $callerDescription, $wgDevelopmentWarnings ? E_USER_DEPRECATED : false );
                }

                if ( self::$enabled ) {
                        $logMsg = htmlspecialchars( $msg ) .
                                Html::rawElement( 'div', array( 'class' => 'mw-debug-backtrace' ),
                                        Html::element( 'span', array(), 'Backtrace:' ) . wfBacktrace()
                                );

                        self::$log[] = array(
                                'msg' => $logMsg,
                                'type' => 'deprecated',
                                'caller' => $callerFunc,
                        );
                }
        }

        /**
         * Get an array describing the calling function at a specified offset.
         *
         * @param $callerOffset integer: How far up the callstack is the original
         *    caller. 0 = function that called getCallerDescription()
         * @return array with two keys: 'file' and 'func'
         */
        private static function getCallerDescription( $callerOffset ) {
                $callers = wfDebugBacktrace();

                if ( isset( $callers[$callerOffset] ) ) {
                        $callerfile = $callers[$callerOffset];
                        if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
                                $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
                        } else {
                                $file = '(internal function)';
                        }
                } else {
                        $file = '(unknown location)';
                }

                if ( isset( $callers[$callerOffset + 1] ) ) {
                        $callerfunc = $callers[$callerOffset + 1];
                        $func = '';
                        if ( isset( $callerfunc['class'] ) ) {
                                $func .= $callerfunc['class'] . '::';
                        }
                        if ( isset( $callerfunc['function'] ) ) {
                                $func .= $callerfunc['function'];
                        }
                } else {
                        $func = 'unknown';
                }

                return array( 'file' => $file, 'func' => $func );
        }

        /**
         * Send a warning to the debug log and optionally also trigger a PHP
         * error, depending on the $level argument.
         *
         * @param $msg string Message to send
         * @param $caller array caller description get from getCallerDescription()
         * @param $level int|bool error level to use; set to false to not trigger an error
         */
        private static function sendWarning( $msg, $caller, $level ) {
                $msg .= ' [Called from ' . $caller['func'] . ' in ' . $caller['file'] . ']';

                if ( $level !== false ) {
                        trigger_error( $msg, $level );
                }

                wfDebug( "$msg\n" );
        }

        /**
         * This is a method to pass messages from wfDebug to the pretty debugger.
         * Do NOT use this method, use MWDebug::log or wfDebug()
         *
         * @since 1.19
         * @param $str string
         */
        public static function debugMsg( $str ) {
                global $wgDebugComments, $wgShowDebug;

                if ( self::$enabled || $wgDebugComments || $wgShowDebug ) {
                        self::$debug[] = rtrim( UtfNormal::cleanUp( $str ) );
                }
        }

        /**
         * Begins profiling on a database query
         *
         * @since 1.19
         * @param $sql string
         * @param $function string
         * @param $isMaster bool
         * @return int ID number of the query to pass to queryTime or -1 if the
         *  debugger is disabled
         */
        public static function query( $sql, $function, $isMaster ) {
                if ( !self::$enabled ) {
                        return -1;
                }

                self::$query[] = array(
                        'sql' => $sql,
                        'function' => $function,
                        'master' => (bool) $isMaster,
                        'time' => 0.0,
                        '_start' => microtime( true ),
                );

                return count( self::$query ) - 1;
        }

        /**
         * Calculates how long a query took.
         *
         * @since 1.19
         * @param $id int
         */
        public static function queryTime( $id ) {
                if ( $id === -1 || !self::$enabled ) {
                        return;
                }

                self::$query[$id]['time'] = microtime( true ) - self::$query[$id]['_start'];
                unset( self::$query[$id]['_start'] );
        }

        /**
         * Returns a list of files included, along with their size
         *
         * @param $context IContextSource
         * @return array
         */
        protected static function getFilesIncluded( IContextSource $context ) {
                $files = get_included_files();
                $fileList = array();
                foreach ( $files as $file ) {
                        $size = filesize( $file );
                        $fileList[] = array(
                                'name' => $file,
                                'size' => $context->getLanguage()->formatSize( $size ),
                        );
                }

                return $fileList;
        }

        /**
         * Returns the HTML to add to the page for the toolbar
         *
         * @since 1.19
         * @param $context IContextSource
         * @return string
         */
        public static function getDebugHTML( IContextSource $context ) {
                global $wgDebugComments;

                $html = '';

                if ( self::$enabled ) {
                        MWDebug::log( 'MWDebug output complete' );
                        $debugInfo = self::getDebugInfo( $context );

                        // Cannot use OutputPage::addJsConfigVars because those are already outputted
                        // by the time this method is called.
                        $html = Html::inlineScript(
                                ResourceLoader::makeLoaderConditionalScript(
                                        ResourceLoader::makeConfigSetScript( array( 'debugInfo' => $debugInfo ) )
                                )
                        );
                }

                if ( $wgDebugComments ) {
                        $html .= "<!-- Debug output:\n" .
                                htmlspecialchars( implode( "\n", self::$debug ) ) .
                                "\n\n-->";
                }

                return $html;
        }

        /**
         * Generate debug log in HTML for displaying at the bottom of the main
         * content area.
         * If $wgShowDebug is false, an empty string is always returned.
         *
         * @since 1.20
         * @return string HTML fragment
         */
        public static function getHTMLDebugLog() {
                global $wgDebugTimestamps, $wgShowDebug;

                if ( !$wgShowDebug ) {
                        return '';
                }

                $curIdent = 0;
                $ret = "\n<hr />\n<strong>Debug data:</strong><ul id=\"mw-debug-html\">\n<li>";

                foreach ( self::$debug as $line ) {
                        $pre = '';
                        if ( $wgDebugTimestamps ) {
                                $matches = array();
                                if ( preg_match( '/^(\d+\.\d+ {1,3}\d+.\dM\s{2})/', $line, $matches ) ) {
                                        $pre = $matches[1];
                                        $line = substr( $line, strlen( $pre ) );
                                }
                        }
                        $display = ltrim( $line );
                        $ident = strlen( $line ) - strlen( $display );
                        $diff = $ident - $curIdent;

                        $display = $pre . $display;
                        if ( $display == '' ) {
                                $display = "\xc2\xa0";
                        }

                        if ( !$ident && $diff < 0 && substr( $display, 0, 9 ) != 'Entering ' && substr( $display, 0, 8 ) != 'Exiting ' ) {
                                $ident = $curIdent;
                                $diff = 0;
                                $display = '<span style="background:yellow;">' . nl2br( htmlspecialchars( $display ) ) . '</span>';
                        } else {
                                $display = nl2br( htmlspecialchars( $display ) );
                        }

                        if ( $diff < 0 ) {
                                $ret .= str_repeat( "</li></ul>\n", -$diff ) . "</li><li>\n";
                        } elseif ( $diff == 0 ) {
                                $ret .= "</li><li>\n";
                        } else {
                                $ret .= str_repeat( "<ul><li>\n", $diff );
                        }
                        $ret .= "<tt>$display</tt>\n";

                        $curIdent = $ident;
                }

                $ret .= str_repeat( '</li></ul>', $curIdent ) . "</li>\n</ul>\n";

                return $ret;
        }

        /**
         * Append the debug info to given ApiResult
         *
         * @param $context IContextSource
         * @param $result ApiResult
         */
        public static function appendDebugInfoToApiResult( IContextSource $context, ApiResult $result ) {
                if ( !self::$enabled ) {
                        return;
                }

                // output errors as debug info, when display_errors is on
                // this is necessary for all non html output of the api, because that clears all errors first
                $obContents = ob_get_contents();
                if ( $obContents ) {
                        $obContentArray = explode( '<br />', $obContents );
                        foreach ( $obContentArray as $obContent ) {
                                if ( trim( $obContent ) ) {
                                        self::debugMsg( Sanitizer::stripAllTags( $obContent ) );
                                }
                        }
                }

                MWDebug::log( 'MWDebug output complete' );
                $debugInfo = self::getDebugInfo( $context );

                $result->setIndexedTagName( $debugInfo, 'debuginfo' );
                $result->setIndexedTagName( $debugInfo['log'], 'line' );
                $result->setIndexedTagName( $debugInfo['debugLog'], 'msg' );
                $result->setIndexedTagName( $debugInfo['queries'], 'query' );
                $result->setIndexedTagName( $debugInfo['includes'], 'queries' );
                $result->addValue( null, 'debuginfo', $debugInfo );
        }

        /**
         * Returns the HTML to add to the page for the toolbar
         *
         * @param $context IContextSource
         * @return array
         */
        public static function getDebugInfo( IContextSource $context ) {
                if ( !self::$enabled ) {
                        return array();
                }

                global $wgVersion, $wgRequestTime;
                $request = $context->getRequest();
                return array(
                        'mwVersion' => $wgVersion,
                        'phpVersion' => PHP_VERSION,
                        'gitRevision' => GitInfo::headSHA1(),
                        'gitBranch' => GitInfo::currentBranch(),
                        'gitViewUrl' => GitInfo::headViewUrl(),
                        'time' => microtime( true ) - $wgRequestTime,
                        'log' => self::$log,
                        'debugLog' => self::$debug,
                        'queries' => self::$query,
                        'request' => array(
                                'method' => $request->getMethod(),
                                'url' => $request->getRequestURL(),
                                'headers' => $request->getAllHeaders(),
                                'params' => $request->getValues(),
                        ),
                        'memory' => $context->getLanguage()->formatSize( memory_get_usage() ),
                        'memoryPeak' => $context->getLanguage()->formatSize( memory_get_peak_usage() ),
                        'includes' => self::getFilesIncluded( $context ),
                );
        }
}