deb-heat/heat/scaling/template.py
Zane Bitter 8998897425 Use add_resource() to build autoscaling templates
Instead of building nested templates for Autoscaling manually, use the
Template.add_resource() method to build them up programmatically.

Change-Id: Ie4d6a869355cf0ddb6fce0edc6c7d49b8a2b7e75
2014-06-05 13:45:14 -04:00

57 lines
2.1 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.
from heat.common import short_id
from heat.engine import template
def resource_templates(old_resources, resource_definition,
num_resources, num_replace):
"""
Create the template for the nested stack of existing and new instances
For rolling update, if launch configuration is different, the
instance definition should come from the existing instance instead
of using the new launch configuration.
"""
old_resources = old_resources[-num_resources:]
num_create = num_resources - len(old_resources)
num_replace -= num_create
for i in range(num_resources):
if i < len(old_resources):
old_name, old_template = old_resources[i]
if old_template != resource_definition and num_replace > 0:
num_replace -= 1
yield old_name, resource_definition
else:
yield old_name, old_template
else:
yield short_id.generate_id(), resource_definition
def make_template(resource_definitions,
version=('heat_template_version', '2013-05-23')):
"""
Return a Template object containing the given resource definitions.
By default, the template will be in the HOT format. A different format
can be specified by passing a (version_type, version_string) tuple matching
any of the available template format plugins.
"""
tmpl = template.Template(dict([version]))
for name, defn in resource_definitions:
tmpl.add_resource(defn, name)
return tmpl