# coding: utf-8
"""
Contains a generic class for file IO.
"""
from abc import ABCMeta, abstractmethod
from can import Listener
[docs]class BaseIOHandler(object):
"""A generic file handler that can be used for reading and writing.
Can be used as a context manager.
:attr file-like file:
the file-like object that is kept internally, or None if none
was opened
"""
__metaclass__ = ABCMeta
def __init__(self, file, mode='rt'):
"""
:param file: a path-like object to open a file, a file-like object
to be used as a file or `None` to not use a file at all
:param str mode: the mode that should be used to open the file, see
:func:`open`, ignored if *file* is `None`
"""
if file is None or (hasattr(file, 'read') and hasattr(file, 'write')):
# file is None or some file-like object
self.file = file
else:
# file is some path-like object
self.file = open(file, mode)
# for multiple inheritance
super(BaseIOHandler, self).__init__()
def __enter__(self):
return self
def __exit__(self, *args):
self.stop()
def stop(self):
if self.file is not None:
# this also implies a flush()
self.file.close()