Python RotatingFileHandler and StreamHandler

flask-logger.py

from flask.globals import _find_app, LocalProxy, partial


def _find_app_attr(name):
    app = _find_app()
    return getattr(app, name)

"""
This can be only used in app context.

app config need LOGGER_HANDLER_POLICY.

dev config:             debug
production config:      production

Use like this:

from app.logging import logger


@app.route('/some'):
def some():
    logger.info()
"""

logger = LocalProxy(partial(_find_app_attr, 'logger'))

log.py

# coding=utf-8

"""
You can use this module to handler log.
Example:
    from app import log as logging

    LOG = logging.getLogger(__name__)

    LOG.debug('Hello')
    LOG.info('Hello')
    LOG.warning('hello')
    LOG.error('hello')
    LOG.critical('hello')
"""

import logging
import os
from logging import config, LoggerAdapter

import six
import yaml

base_dir = os.path.abspath(os.path.dirname(__file__))
LOG_CONF = os.path.join(base_dir, '../logging.yaml')

_loggers = {}

with open(LOG_CONF, 'rb') as f:
    conf = yaml.load(f)
    config.dictConfig(conf)


class ContextAdapter(LoggerAdapter):
    def __init__(self, logger, name):
        self.logger = logger
        self.name = name

    def process(self, msg, kwargs):
        # If msg is not unicode, coerce it into unicode.
        if not isinstance(msg, six.text_type):
            msg = six.text_type(msg)
        return msg, kwargs


def getLogger(name='unknown'):
    if name not in _loggers:
        _loggers[name] = ContextAdapter(logging.getLogger(name), name)
    return _loggers[name]

logging.yaml

---
version: 1
disable_exsiting_loggers: True
formatters:
  default:
    format: '[%(asctime)s] -- %(levelname)s %(name)s %(pathname)s:[%(funcName)s]:(at %(lineno)d) -- %(message)s'
handlers:
  console:
    level: INFO
    class: logging.StreamHandler
    formatter: default
  file:
    level: INFO
    class: logging.handlers.RotatingFileHandler
    formatter: default
    filename: plm.log
    maxBytes: 1024
    backupCount: 3
root:
  handlers: [console, file]
  level: INFO

python-simple-log.py

# coding=utf-8

import logging
from logging.handlers import RotatingFileHandler

def getLogger(name):
    logger = logging.getLogger(name)
    logger.setLevel('INFO')
    formatter = logging.Formatter(
        '%(asctime)s %(levelname)s %(name)s %(message)s '
        '[in %(pathname)s:%(lineno)d]')

    # RotatingFileHandler
    logger_handler = RotatingFileHandler('{}.log'.format(name), maxBytes=10*1024*1024, backupCount=2)
    logger_handler.setLevel('INFO')

    logger_handler.setFormatter(formatter)

    # StreamHandler
    stream_handler = logging.StreamHandler()
    stream_handler.setFormatter(formatter)

    logger.addHandler(logger_handler)
    logger.addHandler(stream_handler)
    return logger