bareon-allocator/bareon_dynamic_allocator/parser.py

83 lines
2.1 KiB
Python

# Copyright 2015 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 then
# License for the specific language governing permissions and limitations
# under the License.
import yaml
import yaql
import six
import re
def seq_iter(obj):
if isinstance(obj, dict):
for k, v in six.iteritems(obj):
yield k, v
elif isinstance(obj, list):
for i in xrange(len(obj)):
yield i, obj[i]
class YAQLParser(object):
engine_options = {
'yaql.limitIterators': 100,
'yaql.treatSetsAsLists': True,
'yaql.memoryQuota': 10000
}
def __init__(self, data, context):
self.factory = yaql.YaqlFactory()
self.parser = self.factory.create(options=self.engine_options)
self.context = context
self.data = data
def parse(self):
return self.parser(self.data).evaluate(self.context)
class NoopParser(object):
def __init__(self, data, _):
self.data = data
def parse(self):
return self.data
class Parser(object):
yaql_re = re.compile(r'^\s*yaql\s*=\s*')
def __init__(self, template, context):
self.template = template
self.context = context
def parse(self):
return self._walk(self.template)
def _walk(self, node):
if isinstance(node, six.string_types):
return self.get_parser(node).parse()
for key, item in seq_iter(node):
node[key] = self._walk(item)
return node
def get_parser(self, node):
if self.yaql_re.match(node):
wo_prefix = self.yaql_re.sub('', node)
return YAQLParser(wo_prefix, self.context)
return NoopParser(node, self.context)