placement/placement/lib.py

54 lines
2.5 KiB
Python

# 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.
"""Symbols intended to be imported by both placement code and placement API
consumers. When placement is separated out, this module should be part of a
common library that both placement and its consumers can require."""
class RequestGroup(object):
def __init__(self, use_same_provider=True, resources=None,
required_traits=None, forbidden_traits=None, member_of=None):
"""Create a grouping of resource and trait requests.
:param use_same_provider:
If True, (the default) this RequestGroup represents requests for
resources and traits which must be satisfied by a single resource
provider. If False, represents a request for resources and traits
in any resource provider in the same tree, or a sharing provider.
:param resources: A dict of { resource_class: amount, ... }
:param required_traits: A set of { trait_name, ... }
:param forbidden_traits: A set of { trait_name, ... }
:param member_of: A list of [ [aggregate_UUID],
[aggregate_UUID, aggregate_UUID] ... ]
"""
self.use_same_provider = use_same_provider
self.resources = resources or {}
self.required_traits = required_traits or set()
self.forbidden_traits = forbidden_traits or set()
self.member_of = member_of or []
def __str__(self):
ret = 'RequestGroup(use_same_provider=%s' % str(self.use_same_provider)
ret += ', resources={%s}' % ', '.join(
'%s:%d' % (rc, amount)
for rc, amount in sorted(list(self.resources.items())))
ret += ', traits=[%s]' % ', '.join(
sorted(self.required_traits) +
['!%s' % ft for ft in self.forbidden_traits])
ret += ', aggregates=[%s]' % ', '.join(
sorted('[%s]' % ', '.join(agglist)
for agglist in sorted(self.member_of)))
ret += ')'
return ret