""" Copyright 2015 Rackspace 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 collections import functools import time import types import netaddr def def_method(f, *args, **kwargs): @functools.wraps(f) def new_method(self): return f(self, *args, **kwargs) return new_method def parameterized_class(cls): """A class decorator for running parameterized test cases. Mark your class with @parameterized_class. Mark your test cases with @parameterized. """ test_functions = { k: v for k, v in vars(cls).items() if k.startswith('test') } for name, f in test_functions.items(): if not hasattr(f, '_test_data'): continue # remove the original test function from the class delattr(cls, name) # add a new test function to the class for each entry in f._test_data for tag, args in f._test_data.items(): new_name = "{0}_{1}".format(f.__name__, tag) if hasattr(cls, new_name): raise Exception( "Parameterized test case '{0}.{1}' created from '{0}.{2}' " "already exists".format(cls.__name__, new_name, name)) # Using `def new_method(self): f(self, **args)` is not sufficient # (all new_methods use the same args value due to late binding). # Instead, use this factory function. new_method = def_method(f, **args) # To add a method to a class, available for all instances: # MyClass.method = types.MethodType(f, None, MyClass) setattr(cls, new_name, types.MethodType(new_method, None, cls)) return cls def parameterized(data): """A function decorator for parameterized test cases. Example: @parameterized({ 'zero': dict(val=0), 'one': dict(val=1), }) def test_val(self, val): self.assertEqual(self.get_val(), val) The above will generate two test cases: `test_val_zero` which runs with val=0 `test_val_one` which runs with val=1 :param data: A dictionary that looks like {tag: {arg1: val1, ...}} """ def wrapped(f): f._test_data = data return f return wrapped def wait_for_condition(condition, interval=5, timeout=45): end_time = time.time() + timeout while time.time() < end_time: result = condition() if result: return result time.sleep(interval) raise Exception("Timed out after {0} seconds".format(timeout)) def memoized(func): """A decorator to cache function's return value""" cache = {} @functools.wraps(func) def wrapper(*args): if not isinstance(args, collections.Hashable): # args is not cacheable. just call the function. return func(*args) if args in cache: return cache[args] else: value = func(*args) cache[args] = value return value return wrapper def shorten_ipv6_addrs(addrs): """Shorten ipv6 addresses""" new_addrs = [] for a in addrs: an = netaddr.IPAddress(a, version=6) new_addrs.append(an.format(netaddr.ipv6_compact)) return new_addrs