includes/debug/logger/LoggerFactory.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  */
  20
  21 namespace MediaWiki\Logger;
  22
  23 use ObjectFactory;
  24
  25 /**
  26  * PSR-3 logger instance factory.
  27  *
  28  * Creation of \Psr\Log\LoggerInterface instances is managed via the
  29  * LoggerFactory::getInstance() static method which in turn delegates to the
  30  * currently registered service provider.
  31  *
  32  * A service provider is any class implementing the Spi interface.
  33  * There are two possible methods of registering a service provider. The
  34  * LoggerFactory::registerProvider() static method can be called at any time
  35  * to change the service provider. If LoggerFactory::getInstance() is called
  36  * before any service provider has been registered, it will attempt to use the
  37  * $wgMWLoggerDefaultSpi global to bootstrap Spi registration.
  38  * $wgMWLoggerDefaultSpi is expected to be an array usable by
  39  * ObjectFactory::getObjectFromSpec() to create a class.
  40  *
  41  * @see \MediaWiki\Logger\Spi
  42  * @since 1.25
  43  * @copyright © 2014 Wikimedia Foundation and contributors
  44  */
  45 class LoggerFactory {
  46
  47         /**
  48          * Service provider.
  49          * @var \MediaWiki\Logger\Spi $spi
  50          */
  51         private static $spi;
  52
  53         /**
  54          * Register a service provider to create new \Psr\Log\LoggerInterface
  55          * instances.
  56          *
  57          * @param \MediaWiki\Logger\Spi $provider Provider to register
  58          */
  59         public static function registerProvider( Spi $provider ) {
  60                 self::$spi = $provider;
  61         }
  62
  63         /**
  64          * Get the registered service provider.
  65          *
  66          * If called before any service provider has been registered, it will
  67          * attempt to use the $wgMWLoggerDefaultSpi global to bootstrap
  68          * Spi registration. $wgMWLoggerDefaultSpi is expected to be an
  69          * array usable by ObjectFactory::getObjectFromSpec() to create a class.
  70          *
  71          * @return \MediaWiki\Logger\Spi
  72          * @see registerProvider()
  73          * @see ObjectFactory::getObjectFromSpec()
  74          */
  75         public static function getProvider() {
  76                 if ( self::$spi === null ) {
  77                         global $wgMWLoggerDefaultSpi;
  78                         $provider = ObjectFactory::getObjectFromSpec(
  79                                 $wgMWLoggerDefaultSpi
  80                         );
  81                         self::registerProvider( $provider );
  82                 }
  83                 return self::$spi;
  84         }
  85
  86         /**
  87          * Get a named logger instance from the currently configured logger factory.
  88          *
  89          * @param string $channel Logger channel (name)
  90          * @return \Psr\Log\LoggerInterface
  91          */
  92         public static function getInstance( $channel ) {
  93                 return self::getProvider()->getLogger( $channel );
  94         }
  95
  96         /**
  97          * Construction of utility class is not allowed.
  98          */
  99         private function __construct() {
 100                 // no-op
 101         }
 102 }