blob: ba2c9f6380633b1b8805cee5496a6b34a8458d5d [file] [log] [blame]
#!/usr/bin/env python
#
# Copyright 2010 Google Inc.
#
# 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.
"""Base operation class."""
__all__ = ['Operation']
class Operation(object):
"""Base class for all mapper operations.
All operations should implement __call__(self, ctx) function, which will be
called upon operation yield.
"""
def __call__(self, ctx):
raise NotImplementedError("__call__() not implemented in %s" %
self.__class__)