abbreviate or shorten the logger name to initials with python logging

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I'm trying to achieve a behavior available in log4j, which is described in this SO Q&A

Instead of the logger producing the following output (notice the full module name)

DEBUG    aproject.bpackage.cclass:filename.py:79 log message 1

I'd like to only have the initials of the logger name:

DEBUG    a.b.c:filename.py:79 log message 1

Trying to figure out the correct format string with the manual, but no mention of initials for the logger name

Note that loggers are initialized with the module name as convention:
logger = logging.getLogger(__name__)

1 Answers

There's no out-of-the-box functionality for this, but you can achieve the desired result using something like this:

import logging

class CustomFormatter(logging.Formatter):
    def format(self, record):
        saved_name = record.name  # save and restore for other formatters if desired
        parts = saved_name.split('.')
        # import pdb; pdb.set_trace()
        record.name = '.'.join(p[0] for p in parts)
        result = super().format(record)
        record.name = saved_name
        return result

h = logging.StreamHandler()
f = CustomFormatter('%(name)-6s %(message)s')
h.setFormatter(f)
root = logging.getLogger()
root.addHandler(h)
root.setLevel(logging.DEBUG)
logging.getLogger('alpha.beta.gamma').debug('foo')
logging.getLogger('delta.epsilon.zeta').debug('bar')
logging.getLogger('eta.theta').debug('baz')

When run, the above script outputs

a.b.g  foo
d.e.z  bar
e.t    baz
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