bareon-allocator/bareon_allocator/parsers/dynamic_schema_parser.py
Evgeniy L 5ed0f74a9c Initial implementation of strategies
There should be a way to declaratively describe each space type
and strategy of its allocation.

Implements blueprint: dynamic-allocation

Change-Id: I66c2f0b90fb94b0496b5d341817688a042161318
2016-04-13 14:31:32 +00:00

92 lines
2.9 KiB
Python

# Copyright 2016 Mirantis, 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.
from oslo_log import log
from bareon_allocator.objects import Disk
from bareon_allocator.objects import Space
from bareon_allocator.parsers import ExpressionsParser
LOG = log.getLogger(__name__)
class DynamicSchemaParser(object):
def __init__(self, hw_info, schema):
self.hw_info = hw_info
self.schema = schema
self.raw_disks = self.hw_info['disks']
self.rendered_spaces = []
self.disks = []
self.spaces = []
# TODO(eli): In the future should be moved into config.
self.strategies = {
'vg': {'strategy': 'container'},
'lv': {'strategy': 'elastic'},
'partitions': {'strategy': 'elastic'}
}
self.parse()
self.post_parse()
def parse(self):
self.render_expressions()
self.disks = [
Disk(**disk)
for disk in self.raw_disks]
for s in self.rendered_spaces:
strategy = self.strategies.get(s['type'], {}).get('strategy')
if strategy == 'elastic':
self.spaces.append(Space(**s))
elif strategy is None:
LOG.warn('There is not strategy for space %s', s)
def post_parse(self):
# Add fake volume Unallocated, in order to be able
# to have only volumes with minimal size, without
# additional space allocation
self.spaces.append(Space(
id='unallocated',
type='unallocated',
none_order=True,
weight=0))
def render_expressions(self):
self.rendered_spaces = self._convert_disks_to_indexes(
ExpressionsParser(self.schema, self.hw_info).parse(),
self.hw_info)
def _convert_disks_to_indexes(self, spaces, hw_info):
"""Convert disks to indexes.
Convert disks which are specified in `best_with_disks`
to a list of indexes in `disks` list.
"""
for i, space in enumerate(spaces):
if space.get('best_with_disks'):
disks_ids = set()
for disk in space['best_with_disks']:
try:
disks_ids.add(disk['id'])
except ValueError as exc:
LOG.warn('Warning: %s', exc)
spaces[i]['best_with_disks'] = disks_ids
return spaces