mitogen/ansible_mitogen/logging.py

# Copyright 2017, David Wilson
#
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# modification, are permitted provided that the following conditions are met:
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# 1. Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
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# this list of conditions and the following disclaimer in the documentation
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from __future__ import absolute_import
import logging
import os
import sys

import mitogen.core
import mitogen.utils


class Handler(logging.Handler):
    """
    Use Mitogen's log format, but send the result to a Display method.
    """
    def __init__(self, display, normal_method):
        super(Handler, self).__init__()
        self.formatter = mitogen.utils.log_get_formatter(usec=True)
        self.display = display
        self.normal_method = normal_method

    def emit(self, record):
        if getattr(record, 'mitogen_name', '') == 'stderr':
            record.levelno = logging.ERROR

        s = '[pid %d] %s' % (os.getpid(), self.format(record))
        if record.levelno >= logging.ERROR:
            self.display.error(s, wrap_text=False)
        elif record.levelno >= logging.WARNING:
            self.display.warning(s, formatted=True)
        else:
            self.normal_method(s)


def find_display():
    """
    Find the CLI tool's display variable somewhere up the stack. Why god why,
    right? Because it's the the simplest way to get access to the verbosity
    configured on the command line.
    """
    f = sys._getframe()
    while f:
        if 'display' in f.f_locals:
            return f.f_locals['display']
        f = f.f_back


def setup():
    """
    Install a handler for Mitogen's logger to redirect it into the Ansible
    display framework, and prevent propagation to the root logger.
    """
    display = find_display()

    logging.getLogger('ansible_mitogen').handlers = [Handler(display, display.vvv)]
    mitogen.core.LOG.handlers = [Handler(display, display.vvv)]
    mitogen.core.IOLOG.handlers = [Handler(display, display.vvvv)]
    mitogen.core.IOLOG.propagate = False

    if display.verbosity > 2:
        logging.getLogger('ansible_mitogen').setLevel(logging.DEBUG)
        mitogen.core.LOG.setLevel(logging.DEBUG)

    if display.verbosity > 3:
        mitogen.core.IOLOG.setLevel(logging.DEBUG)