https://github.com/python/cpython/commit/552478bb1086ef371e4f1da0b430b90eba4... commit: 552478bb1086ef371e4f1da0b430b90eba4785d5 branch: 3.7 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: Vinay Sajip <vinay_sajip@yahoo.co.uk> date: 2019-01-23T07:21:32Z summary: bpo-35722: Updated the documentation for the 'disable_existing_loggers' parameter (GH-11525) (GH-11655) (cherry picked from commit f0c743604fc841d35a48822b936ef2e5919e43c1) Co-authored-by: Géry Ogam <gery.ogam@gmail.com> files: M Doc/howto/logging.rst M Doc/library/logging.config.rst diff --git a/Doc/howto/logging.rst b/Doc/howto/logging.rst index 2a2282e9ecf0..c90df4301fa6 100644 --- a/Doc/howto/logging.rst +++ b/Doc/howto/logging.rst @@ -695,15 +695,15 @@ noncoders to easily modify the logging properties. .. warning:: The :func:`fileConfig` function takes a default parameter, ``disable_existing_loggers``, which defaults to ``True`` for reasons of backward compatibility. This may or may not be what you want, since it - will cause any loggers existing before the :func:`fileConfig` call to - be disabled unless they (or an ancestor) are explicitly named in the - configuration. Please refer to the reference documentation for more + will cause any non-root loggers existing before the :func:`fileConfig` + call to be disabled unless they (or an ancestor) are explicitly named in + the configuration. Please refer to the reference documentation for more information, and specify ``False`` for this parameter if you wish. The dictionary passed to :func:`dictConfig` can also specify a Boolean value with key ``disable_existing_loggers``, which if not specified explicitly in the dictionary also defaults to being interpreted as - ``True``. This leads to the logger-disabling behaviour described above, + ``True``. This leads to the logger-disabling behaviour described above, which may not be what you want - in which case, provide the key explicitly with a value of ``False``. @@ -802,7 +802,7 @@ the best default behaviour. If for some reason you *don't* want these messages printed in the absence of any logging configuration, you can attach a do-nothing handler to the top-level logger for your library. This avoids the message being printed, since a handler -will be always be found for the library's events: it just doesn't produce any +will always be found for the library's events: it just doesn't produce any output. If the library user configures logging for application use, presumably that configuration will add some handlers, and if levels are suitably configured then logging calls made in library code will send output to those diff --git a/Doc/library/logging.config.rst b/Doc/library/logging.config.rst index de805eb955df..cd62adb39a36 100644 --- a/Doc/library/logging.config.rst +++ b/Doc/library/logging.config.rst @@ -107,9 +107,9 @@ in :mod:`logging` itself) and defining handlers which are declared either in enabled. The default is ``True`` because this enables old behaviour in a backward-compatible way. This behaviour is to - disable any existing loggers unless they or - their ancestors are explicitly named in the - logging configuration. + disable any existing non-root loggers unless + they or their ancestors are explicitly named + in the logging configuration. .. versionchanged:: 3.4 An instance of a subclass of :class:`~configparser.RawConfigParser` is @@ -308,8 +308,8 @@ otherwise, the context is used to determine what to instantiate. If the specified value is ``True``, the configuration is processed as described in the section on :ref:`logging-config-dict-incremental`. -* *disable_existing_loggers* - whether any existing loggers are to be - disabled. This setting mirrors the parameter of the same name in +* *disable_existing_loggers* - whether any existing non-root loggers are + to be disabled. This setting mirrors the parameter of the same name in :func:`fileConfig`. If absent, this parameter defaults to ``True``. This value is ignored if *incremental* is ``True``.