Charmed-Kubernetes/nrpe/mod/charmhelpers/tests/helpers.py

145 lines
4.3 KiB
Python

''' General helper functions for tests '''
from contextlib import contextmanager
from mock import patch, MagicMock
import io
import six
if not six.PY3:
builtin_open = '__builtin__.open'
else:
builtin_open = 'builtins.open'
@contextmanager
def patch_open():
'''Patch open() to allow mocking both open() itself and the file that is
yielded.
Yields the mock for "open" and "file", respectively.'''
mock_open = MagicMock(spec=open)
mock_file = MagicMock(spec=io.FileIO)
@contextmanager
def stub_open(*args, **kwargs):
mock_open(*args, **kwargs)
yield mock_file
with patch(builtin_open, stub_open):
yield mock_open, mock_file
@contextmanager
def mock_open(filename, contents=None):
''' Slightly simpler mock of open to return contents for filename '''
def mock_file(name, mode='r', buffering=-1): # Python 2 signature.
if name == filename:
if (not six.PY3) or 'b' in mode:
return io.BytesIO(contents)
return io.StringIO(contents)
else:
return open(name, mode, buffering)
with patch(builtin_open, mock_file):
yield
class FakeRelation(object):
'''
A fake relation class. Lets tests specify simple relation data
for a default relation + unit (foo:0, foo/0, set in setUp()), eg:
rel = {
'private-address': 'foo',
'password': 'passwd',
}
relation = FakeRelation(rel)
self.relation_get.side_effect = relation.get
passwd = self.relation_get('password')
or more complex relations meant to be addressed by explicit relation id
+ unit id combos:
rel = {
'mysql:0': {
'mysql/0': {
'private-address': 'foo',
'password': 'passwd',
}
}
}
relation = FakeRelation(rel)
self.relation_get.side_affect = relation.get
passwd = self.relation_get('password', rid='mysql:0', unit='mysql/0')
set_relation_context can be used to simulate being in a relation hook
context. This allows omitting a relation id or unit when calling relation
helpers as the related unit is present.
To set the context:
relation = FakeRelation(rel)
relation.set_relation_context('mysql-svc2/0', 'shared-db:12')
To clear it:
relation.clear_relation_context()
'''
def __init__(self, relation_data):
self.relation_data = relation_data
self.remote_unit = None
self.current_relation_id = None
def set_relation_context(self, remote_unit, relation_id):
self.remote_unit = remote_unit
self.current_relation_id = relation_id
def clear_relation_context(self):
self.remote_unit = None
self.current_relation_id = None
def get(self, attribute=None, unit=None, rid=None):
if not rid or rid == 'foo:0':
if self.current_relation_id:
if not unit:
unit = self.remote_unit
udata = self.relation_data[self.current_relation_id][unit]
if attribute:
return udata[attribute]
else:
return udata[unit]
if attribute is None:
return self.relation_data
elif attribute in self.relation_data:
return self.relation_data[attribute]
return None
else:
if rid not in self.relation_data:
return None
try:
relation = self.relation_data[rid][unit]
except KeyError:
return None
if attribute and attribute in relation:
return relation[attribute]
return relation
def relation_id(self):
return self.current_relation_id
def relation_ids(self, reltype=None):
rids = self.relation_data.keys()
if reltype:
return [r for r in rids if r.split(':')[0] == reltype]
return rids
def related_units(self, relid=None):
try:
return self.relation_data[relid].keys()
except KeyError:
return []
def relation_units(self, relation_id):
if relation_id not in self.relation_data:
return None
return self.relation_data[relation_id].keys()