Files
deb-python-taskflow/taskflow/logbook.py
2013-05-13 14:11:51 -07:00

71 lines
2.1 KiB
Python

# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright (C) 2012 Yahoo! Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import abc
from datetime import datetime
class Entry(object):
"""A logbook entry has the bare minimum of these fields."""
def __init__(self, name, metadata=None):
self.created_on = datetime.utcnow()
self.name = name
self.metadata = metadata
class LogBook(object):
"""Base class for what a logbook (distributed or local or in-between)
should provide"""
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def add(self, entry):
"""Atomically adds a new entry to the given logbook."""
raise NotImplementedError()
def search_by_name(self, name):
"""Yields entries with the given name. The order will be in the same
order that they were added."""
for e in self:
if e.name == name:
yield e
@abc.abstractmethod
def __contains__(self, name):
"""Determines if any entry with the given name exists in this
logbook."""
raise NotImplementedError()
@abc.abstractmethod
def __iter__(self):
"""Iterates over all entries. The order will be in the same order that
they were added."""
raise NotImplementedError()
@abc.abstractmethod
def erase(self, name):
"""Erases any entries with given name."""
raise NotImplementedError()
def close(self):
"""Allows the logbook to free any resources that it has."""
pass