From 2bf551757e0a7e3cc6ce2ebed2178b82438ac6b5 Mon Sep 17 00:00:00 2001 From: Vinay Sajip Date: Tue, 7 Dec 2021 11:15:44 +0000 Subject: [PATCH] bpo-35821: Add an example to Logger.propagate documentation. (GH-29841) --- Doc/library/logging.rst | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst index 3f3a8534f54..e7c64e5ba40 100644 --- a/Doc/library/logging.rst +++ b/Doc/library/logging.rst @@ -80,6 +80,15 @@ is the module's name in the Python package namespace. If this evaluates to false, logging messages are not passed to the handlers of ancestor loggers. + Spelling it out with an example: If the propagate attribute of the logger named + `A.B.C` evaluates to true, any event logged to `A.B.C` via a method call such as + `logging.getLogger('A.B.C').error(...)` will [subject to passing that logger's + level and filter settings] be passed in turn to any handlers attached to loggers + named `A.B`, `A` and the root logger, after first being passed to any handlers + attached to `A.B.C`. If any logger in the chain `A.B.C`, `A.B`, `A` has its + `propagate` attribute set to false, then that is the last logger whose handlers + are offered the event to handle, and propagation stops at that point. + The constructor sets this attribute to ``True``. .. note:: If you attach a handler to a logger *and* one or more of its