title: How to configure YAML to create fresh log files instead of appending them?
body: <p>In a python logger implementation given below, each time I run my program, the logs are <em>appended</em> each time to the existing log files. How do I ensure that each time I run my application code, they are written to the fresh log file? </p>
  
  <p>Is it happening because I have set the RotatingFileHandler with backup count as 20 with each file size of 10MB? Should I convert it to simple file handler? </p>
  
  <p>I am using following yaml based log configuration in my python logger. </p>
  
  <pre><code>  1 version: 1
    2
    3 formatters:
    4   simple:
    5     format: '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
    6
    7 handlers:
    8   console:
    9     class: logging.StreamHandler
   10     level: DEBUG
   11     formatter: simple
   12     stream: ext://sys.stdout
   13
   14   info_handler:
   15     class: logging.handlers.RotatingFileHandler
   16     level: INFO
   17     formatter: simple
   18     filename: info.log
   19     maxBytes: 10485760 # 10MB
   20     backupCount: 20
   21     encoding: utf8
   22
   23   error_handler:
   24     class: logging.handlers.RotatingFileHandler
   25     level: ERROR
   26     formatter: simple
   27     filename: errors.log
   28     maxBytes: 10485760 # 10MB
   29     backupCount: 20
   30     encoding: utf8
   31
   32 loggers:
   33   my_module:
   34     level: ERROR
   35     handlers: [console]
   36     propagate: no
   37
   38 root:
   39   level: DEBUG
   40   handlers: [info_handler, info_handler]
  </code></pre>
  
  <p>I am using the following python logger initializer code to initialize my logger. </p>
  
  <pre><code>  1 import os
    2 import logging.config
    3 import yaml
    4
    5 """Setup logging configuration """
    6 default_path='logging.yaml'
    7 default_level=logging.INFO
    8 env_key='LOG_CFG'
    9
   10 class MyLogger():
   11
   12     def __init__(self):
   13         path = default_path
   14         value = os.getenv(env_key, None)
   15         if value:
   16             path = value
   17         if os.path.exists(path):
   18             with open(path, 'rt') as f:
   19                 config = yaml.safe_load(f.read())
   20             logging.config.dictConfig(config)
   21         else:
   22             logging.basicConfig(filemode='w', level=default_level)
  </code></pre>