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                # Licensed to the StackStorm, Inc ('StackStorm') under one or more | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # contributor license agreements.  See the NOTICE file distributed with  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # this work for additional information regarding copyright ownership.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # The ASF licenses this file to You under the Apache License, Version 2.0  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # (the "License"); you may not use this file except in compliance with  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    6
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                # the License.  You may obtain a copy of the License at  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                #  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                #     http://www.apache.org/licenses/LICENSE-2.0  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                #  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # Unless required by applicable law or agreed to in writing, software  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # distributed under the License is distributed on an "AS IS" BASIS,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # See the License for the specific language governing permissions and  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                # limitations under the License.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                from __future__ import absolute_import  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                import sys  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    19
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                import logging  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    20
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                import logging.config  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                import logging.handlers  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                import traceback  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    23
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                from functools import wraps  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    24
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                    25
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                import six  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    26
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                from oslo_config import cfg  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    27
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                    28
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                from st2common.logging.filters import ExclusionFilter  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    29
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                    30
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                # Those are here for backward compatibility reasons  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    31
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                from st2common.logging.handlers import FormatNamedFileHandler  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                from st2common.logging.handlers import ConfigurableSyslogHandler  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    33
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                from st2common.util.misc import prefix_dict_keys  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    34
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                    35
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                __all__ = [  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    36
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                    'getLogger',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    37
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                    'setup',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    38
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                    39
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                    'FormatNamedFileHandler',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    40
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                    'ConfigurableSyslogHandler',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    41
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                    42
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                    'LoggingStream'  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    43
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                ]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    44
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                    45
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                logging.AUDIT = logging.CRITICAL + 10  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    46
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                logging.addLevelName(logging.AUDIT, 'AUDIT')  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    48
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                LOGGER_KEYS = [  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    49
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                    'debug',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    50
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                    'info',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    51
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                    'warning',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    52
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                    'error',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    53
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                    'critical',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    54
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                    'exception',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    55
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                    'log',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    56
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                    57
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                    'audit'  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    58
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                ]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    59
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                    60
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                    61
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                def decorate_log_method(func):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    62
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                    @wraps(func)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    63
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                    def func_wrapper(*args, **kwargs):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    64
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                        # Prefix extra keys with underscore  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    65
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                        if 'extra' in kwargs:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    66
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                            kwargs['extra'] = prefix_dict_keys(dictionary=kwargs['extra'], prefix='_')  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    67
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                        try:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return func(*args, **kwargs)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    70
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                        except TypeError as e:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            # In some version of Python 2.7, logger.exception doesn't take any kwargs so we need  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    72
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                            # this hack :/  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    73
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                            # See:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    74
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                            # - https://docs.python.org/release/2.7.3/library/logging.html#logging.Logger.exception  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            # - https://docs.python.org/release/2.7.7/library/logging.html#logging.Logger.exception  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    76
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                            if 'got an unexpected keyword argument \'extra\'' in str(e):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                kwargs.pop('extra', None) | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                return func(*args, **kwargs)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            raise e  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    80
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                    return func_wrapper  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    81
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                    82
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                    83
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                def decorate_logger_methods(logger):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    84
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                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    85
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                    Decorate all the logger methods so all the keys in the extra dictionary are  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    86
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                    automatically prefixed with an underscore to avoid clashes with standard log  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    87
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                    record attributes.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    88
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                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    89
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                    for key in LOGGER_KEYS:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    90
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                        log_method = getattr(logger, key)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        log_method = decorate_log_method(log_method)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    92
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                        setattr(logger, key, log_method)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    93
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                    94
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                    return logger  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    95
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                    96
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                    97
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                def getLogger(name):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    98
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                    logger_name = 'st2.{}'.format(name) | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    logger = logging.getLogger(logger_name)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    100
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                    logger = decorate_logger_methods(logger=logger)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    101
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                    return logger  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    102
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                    103
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                    104
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                class LoggingStream(object):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    105
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                    106
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                    def __init__(self, name, level=logging.ERROR):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    107
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                        self._logger = getLogger(name)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    108
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                        self._level = level  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    109
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                    110
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                    def write(self, message):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    111
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                 | 
                        self._logger._log(self._level, message, None)  | 
            
                            
                    | 
                        
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                     | 
                     | 
                    
                                                                                                    
                        
                         
                                                                                        
                                                                                     
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                    112
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                    113
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                    114
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                def _audit(logger, msg, *args, **kwargs):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    115
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                    if logger.isEnabledFor(logging.AUDIT):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    116
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                        logger._log(logging.AUDIT, msg, args, **kwargs)  | 
            
                            
                    | 
                        
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                     | 
                     | 
                    
                                                                                                    
                        
                         
                                                                                        
                                                                                     
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                    117
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                    118
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                logging.Logger.audit = _audit  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    119
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                    120
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                | 
                    121
                 | 
                                    
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                def _add_exclusion_filters(handlers):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    122
                 | 
                                    
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                 | 
                    for h in handlers:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    123
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                 | 
                        h.addFilter(ExclusionFilter(cfg.CONF.log.excludes))  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    124
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                    125
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                | 
                    126
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                def _redirect_stderr():  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    127
                 | 
                                    
                                                     | 
                
                 | 
                    # It is ok to redirect stderr as none of the st2 handlers write to stderr.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    128
                 | 
                                    
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                    if cfg.CONF.log.redirect_stderr:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    129
                 | 
                                    
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                 | 
                        sys.stderr = LoggingStream('STDERR') | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    130
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                    131
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                 | 
            
            
                                                        
            
                                    
            
            
                | 
                    132
                 | 
                                    
                                                     | 
                
                 | 
                def setup(config_file, disable_existing_loggers=False):  | 
            
            
                                                        
            
                                    
            
            
                | 
                    133
                 | 
                                    
                                                     | 
                
                 | 
                    """  | 
            
            
                                                        
            
                                    
            
            
                | 
                    134
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                                                     | 
                
                 | 
                    Configure logging from file.  | 
            
            
                                                        
            
                                    
            
            
                | 
                    135
                 | 
                                    
                                                     | 
                
                 | 
                    """  | 
            
            
                                                        
            
                                    
            
            
                | 
                    136
                 | 
                                    
                                                     | 
                
                 | 
                    try:  | 
            
            
                                                        
            
                                    
            
            
                | 
                    137
                 | 
                                    
                                                     | 
                
                 | 
                        logging.config.fileConfig(config_file,  | 
            
            
                                                        
            
                                    
            
            
                | 
                    138
                 | 
                                    
                                                     | 
                
                 | 
                                                  defaults=None,  | 
            
            
                                                        
            
                                    
            
            
                | 
                    139
                 | 
                                    
                                                     | 
                
                 | 
                                                  disable_existing_loggers=disable_existing_loggers)  | 
            
            
                                                        
            
                                    
            
            
                | 
                    140
                 | 
                                    
                                                     | 
                
                 | 
                        handlers = logging.getLoggerClass().manager.root.handlers  | 
            
            
                                                        
            
                                    
            
            
                | 
                    141
                 | 
                                    
                                                     | 
                
                 | 
                        _add_exclusion_filters(handlers)  | 
            
            
                                                        
            
                                    
            
            
                | 
                    142
                 | 
                                    
                                                     | 
                
                 | 
                        _redirect_stderr()  | 
            
            
                                                        
            
                                    
            
            
                | 
                    143
                 | 
                                    
                                                     | 
                
                 | 
                    except Exception as exc:  | 
            
            
                                                        
            
                                    
            
            
                | 
                    144
                 | 
                                    
                                                     | 
                
                 | 
                        # revert stderr redirection since there is no logger in place.  | 
            
            
                                                        
            
                                    
            
            
                | 
                    145
                 | 
                                    
                                                     | 
                
                 | 
                        sys.stderr = sys.__stderr__  | 
            
            
                                                        
            
                                    
            
            
                | 
                    146
                 | 
                                    
                                                     | 
                
                 | 
                        # No logger yet therefore write to stderr  | 
            
            
                                                        
            
                                    
            
            
                | 
                    147
                 | 
                                    
                                                     | 
                
                 | 
                        sys.stderr.write('ERROR: %s' % traceback.format_exc()) | 
            
            
                                                        
            
                                    
            
            
                | 
                    148
                 | 
                                    
                                                     | 
                
                 | 
                        raise Exception(six.text_type(exc))  | 
            
            
                                                        
            
                                    
            
            
                | 
                    149
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                        
Prefixing a member variable
_is usually regarded as the equivalent of declaring it with protected visibility that exists in other languages. Consequentially, such a member should only be accessed from the same class or a child class: