heat/heat/engine/environment.py

100 lines
3.6 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# 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.
# The environment should look like this:
# Note: the base_url, urls and files should be handled earlier
# and by the time it gets to the engine they are all just names.
#
# Use case 1: I want to use all the resource types from provider X
#resource_registry:
# "OS::*": "Dreamhost::*"
# # could also use a url like this (assuming they could all be
# # expressed in nested stacks)
# "OS::*": http://dreamhost.com/bla/resources-types/*"
#
# Use case 2: I want to use mostly the default resources except my
# custom one for a particular resource in the template.
#resource_registry:
# resources:
# my_db_server:
# "OS::DBInstance": file://~/all_my_cool_templates/db.yaml
#
# Use case 3: I always want to always map resource type X to Y
#resource_registry:
# "OS::Networking::FloatingIP": "OS::Nova::FloatingIP"
# "OS::Loadbalancer": file://~/all_my_cool_templates/lb.yaml
#
# Use case 4: I use custom resources a lot and want to shorten the
# url/path
#resource_registry:
# base_url: http://bla.foo/long/url/
# resources:
# my_db_server:
# "OS::DBInstance": dbaas.yaml
#
# Use case 5: I want to put some common parameters in the environment
#parameters:
# KeyName: heat_key
# InstanceType: m1.large
# DBUsername: wp_admin
# LinuxDistribution: F17
class Environment(object):
def __init__(self, env=None):
"""Create an Environment from a dict of varing format.
1) old-school flat parameters
2) or newer {resource_registry: bla, parameters: foo}
:param env: the json environment
"""
if env is None:
env = {}
self.resource_registry = env.get('resource_registry', {})
if 'resources' not in self.resource_registry:
self.resource_registry['resources'] = {}
if 'parameters' in env:
self.params = env['parameters']
else:
self.params = dict((k, v) for (k, v) in env.iteritems()
if k != 'resource_registry')
def get_resource_type(self, resource_type, resource_name):
"""Get the specific resource type that the user wants to implement
'resource_type'.
"""
impl = self.resource_registry['resources'].get(resource_name)
if impl and resource_type in impl:
return impl[resource_type]
# handle: "OS::Compute::Server" -> "Rackspace::Compute::Server"
impl = self.resource_registry.get(resource_type)
if impl:
return impl
# handle: "OS::*" -> "Dreamhost::*"
for k, v in iter(self.resource_registry.items()):
if k.endswith('*'):
orig_prefix = k[:-1]
if resource_type.startswith(orig_prefix):
return v[:-1] + resource_type[len(orig_prefix):]
# no special handling, just return what we were given.
return resource_type
def user_env_as_dict(self):
"""Get the environment as a dict, ready for storing in the db."""
return {'resource_registry': self.resource_registry,
'parameters': self.params}