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-rw-r--r--Doc/howto/logging-cookbook.rst34
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diff --git a/Doc/howto/logging-cookbook.rst b/Doc/howto/logging-cookbook.rst
index e113564..efd8c1c 100644
--- a/Doc/howto/logging-cookbook.rst
+++ b/Doc/howto/logging-cookbook.rst
@@ -1094,6 +1094,40 @@ parentheses go around the format string and the arguments, not just the format
string. That's because the __ notation is just syntax sugar for a constructor
call to one of the XXXMessage classes.
+If you prefer, you can use a :class:`LoggerAdapter` to achieve a similar effect
+to the above, as in the following example::
+
+ import logging
+
+ class Message(object):
+ def __init__(self, fmt, args):
+ self.fmt = fmt
+ self.args = args
+
+ def __str__(self):
+ return self.fmt.format(*self.args)
+
+ class StyleAdapter(logging.LoggerAdapter):
+ def __init__(self, logger, extra=None):
+ super(StyleAdapter, self).__init__(logger, extra or {})
+
+ def log(self, level, msg, *args, **kwargs):
+ if self.isEnabledFor(level):
+ msg, kwargs = self.process(msg, kwargs)
+ self.logger._log(level, Message(msg, args), (), **kwargs)
+
+ logger = StyleAdapter(logging.getLogger(__name__))
+
+ def main():
+ logger.debug('Hello, {}', 'world!')
+
+ if __name__ == '__main__':
+ logging.basicConfig(level=logging.DEBUG)
+ main()
+
+The above script should log the message ``Hello, world!`` when run with
+Python 3.2 or later.
+
.. currentmodule:: logging