352 of components: loggers, handlers, filters, and formatters.
355 * Handlers send the log records (created by loggers) to the appropriate
361 Log event information is passed between loggers, handlers, filters and
413 The flow of log event information in loggers and handlers is illustrated in the
425 objects pass along relevant log messages to all interested log handlers.
439   handler objects from the logger object.  Handlers are covered in more detail
483 determine whether the event is passed to the logger's handlers.
485 Child loggers propagate messages up to the handlers associated with their
487 handlers for all the loggers an application uses. It is sufficient to
488 configure handlers for a top-level logger and create child loggers as needed.
495 Handlers  section in Advanced Logging Tutorial
504 email address. This scenario requires three individual handlers where each
509 :ref:`useful-handlers`); the tutorials use mainly :class:`StreamHandler` and
515 custom handlers) are the following configuration methods:
520   determines which severity of messages it will pass to its handlers.  The level
527   configure and deconfigure filter objects on handlers.
531 defines the interface that all handlers should have and establishes some
589 1. Creating loggers, handlers, and formatters explicitly using Python
663     [handlers]
671     handlers=consoleHandler
675     handlers=consoleHandler
724 :class:`~logging.handlers.WatchedFileHandler` (relative to the logging module) or
750     handlers:
759         handlers: [console]
763       handlers: [console]
772 where a logging event needs to be output, but no handlers can be found to
782   'No handlers could be found for logger X.Y.Z' is printed once.
815 that configuration will add some handlers, and if levels are suitably
817 handlers, as normal.
834 .. note:: It is strongly advised that you *do not add any handlers other
836    because the configuration of handlers is the prerogative of the application
838    target audience and what handlers are most appropriate for their
839    application: if you add handlers 'under the hood', you might well interfere
881 :dfn:`handlers`, which are instances of subclasses of the :class:`Handler`
882 class. Handlers are responsible for ensuring that a logged message (in the form
885 support desk staff, system administrators, developers). Handlers are passed
887 can have zero, one or more handlers associated with it (via the
889 handlers directly associated with a logger, *all handlers associated with all
892 passing to ancestor handlers stops).
894 Just as for loggers, handlers can have levels associated with them. A handler's
915 .. _useful-handlers:
917 Useful Handlers
928 #. :class:`~handlers.BaseRotatingHandler` is the base class for handlers that
930    directly. Instead, use :class:`~handlers.RotatingFileHandler` or
931    :class:`~handlers.TimedRotatingFileHandler`.
933 #. :class:`~handlers.RotatingFileHandler` instances send messages to disk
936 #. :class:`~handlers.TimedRotatingFileHandler` instances send messages to
939 #. :class:`~handlers.SocketHandler` instances send messages to TCP/IP
942 #. :class:`~handlers.DatagramHandler` instances send messages to UDP
945 #. :class:`~handlers.SMTPHandler` instances send messages to a designated
948 #. :class:`~handlers.SysLogHandler` instances send messages to a Unix
951 #. :class:`~handlers.NTEventLogHandler` instances send messages to a
954 #. :class:`~handlers.MemoryHandler` instances send messages to a buffer
957 #. :class:`~handlers.HTTPHandler` instances send messages to an HTTP
960 #. :class:`~handlers.WatchedFileHandler` instances watch the file they are
965 #. :class:`~handlers.QueueHandler` instances send messages to a queue, such as
970    handlers could be found for logger XXX' message which can be displayed if
978    The :class:`~handlers.QueueHandler` class.
981 classes are defined in the core logging package. The other handlers are
982 defined in a sub-module, :mod:`logging.handlers`. (There is also another
990 :class:`~handlers.BufferingFormatter` can be used. In addition to the format
997 Before deciding to process a message further, both loggers and handlers consult
1044 :class:`~handlers.SocketHandler` emits an event by pickling it and sending it
1097 Also note that the core logging module only includes the basic handlers. If
1098 you don't import :mod:`logging.handlers` and :mod:`logging.config`, they won't
1109    Module :mod:`logging.handlers`
1110       Useful handlers included with the logging module.