docs/mwlogger.txt

   1 MWLoggerFactory implements a PSR-3 [0] compatible message logging system.
   2
   3 Named Psr\Log\LoggerInterface instances can be obtained from the
   4 MWLoggerFactory::getInstance() static method. MWLoggerFactory expects a class
   5 implementing the MWLoggerSpi interface to act as a factory for new
   6 Psr\Log\LoggerInterface instances.
   7
   8 The "Spi" in MWLoggerSpi stands for "service provider interface". A SPI is
   9 an API intended to be implemented or extended by a third party. This software
  10 design pattern is intended to enable framework extension and replaceable
  11 components. It is specifically used in the MWLoggerFactory service to allow
  12 alternate PSR-3 logging implementations to be easily integrated with
  13 MediaWiki.
  14
  15 The MWLoggerFactory::getInstance() static method is the means by which most
  16 code acquires a Psr\Log\LoggerInterface instance. This in turn delegates
  17 creation of Psr\Log\LoggerInterface instances to a class implementing the
  18 MWLoggerSpi service provider interface.
  19
  20 The service provider interface allows the backend logging library to be
  21 implemented in multiple ways. The $wgMWLoggerDefaultSpi global provides the
  22 classname of the default MWLoggerSpi implementation to be loaded at runtime.
  23 This can either be the name of a class implementing the MWLoggerSpi with
  24 a zero argument constructor or a callable that will return an MWLoggerSpi
  25 instance. Alternately the MWLoggerFactory::registerProvider method can be
  26 called to inject an MWLoggerSpi instance into MWLoggerFactory and bypass the
  27 use of this configuration variable.
  28
  29 The MWLoggerLegacySpi class implements a service provider to generate
  30 MWLoggerLegacyLogger instances. The MWLoggerLegacyLogger class implements the
  31 PSR-3 logger interface and provides output and configuration equivalent to the
  32 historic logging output of wfDebug, wfDebugLog, wfLogDBError and wfErrorLog.
  33 The MWLoggerLegacySpi class is the default service provider configured in
  34 DefaultSettings.php. It's usage should be transparent for users who are not
  35 ready or do not wish to switch to a alternate logging platform.
  36
  37 The MWLoggerMonologSpi class implements a service provider to generate
  38 Psr\Log\LoggerInterface instances that use the Monolog [1] logging library.
  39 See the PHP docs (or source) for MWLoggerMonologSpi for details on the
  40 configuration of this provider. The default configuration installs a null
  41 handler that will silently discard all logging events. The documentation
  42 provided by the class describes a more feature rich logging configuration.
  43
  44 == Classes ==
  45 ; MWLoggerFactory
  46 : Factory for Psr\Log\LoggerInterface loggers
  47 ; MWLoggerSpi
  48 : Service provider interface for MWLoggerFactory
  49 ; MWLoggerNullSpi
  50 : MWLoggerSpi for creating instances that discard all log events
  51 ; MWLoggerLegacySpi
  52 : Service provider for creating MWLoggerLegacyLogger instances
  53 ; MWLoggerLegacyLogger
  54 : PSR-3 logger that mimics the historical output and configuration of wfDebug,
  55   wfErrorLog and other global logging functions.
  56 ; MWLoggerMonologSpi
  57 : MWLoggerSpi for creating instances backed by the monolog logging library
  58 ; MwLoggerMonologHandler
  59 : Monolog handler that replicates the udp2log and file logging
  60   functionality of wfErrorLog()
  61 ; MwLoggerMonologProcessor
  62 : Monolog log processer that adds host: wfHostname() and wiki: wfWikiID()
  63   to all records
  64
  65 == Globals ==
  66 ; $wgMWLoggerDefaultSpi
  67 : Specification for creating the default service provider interface to use
  68   with MWLoggerFactory
  69
  70 [0]: https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-3-logger-interface.md
  71 [1]: https://github.com/Seldaek/monolog