osprofiler/osprofiler/cmd/cliutils.py

58 lines
1.7 KiB
Python

# Copyright 2014 Mirantis 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 os
def env(*args, **kwargs):
"""Returns the first environment variable set.
If all are empty, defaults to '' or keyword arg `default`.
"""
for arg in args:
value = os.environ.get(arg)
if value:
return value
return kwargs.get("default", "")
def arg(*args, **kwargs):
"""Decorator for CLI args.
Example:
>>> @arg("name", help="Name of the new entity")
... def entity_create(args):
... pass
"""
def _decorator(func):
add_arg(func, *args, **kwargs)
return func
return _decorator
def add_arg(func, *args, **kwargs):
"""Bind CLI arguments to a shell.py `do_foo` function."""
if not hasattr(func, "arguments"):
func.arguments = []
# NOTE(sirp): avoid dups that can occur when the module is shared across
# tests.
if (args, kwargs) not in func.arguments:
# Because of the semantics of decorator composition if we just append
# to the options list positional options will appear to be backwards.
func.arguments.insert(0, (args, kwargs))