deb-heat/heat/engine/resources/template_resource.py
huangtianhua a1336e2527 Move resource inheritance class to engine/resources
Move the resources which inherit from 'Resource'
to engine/resources, such as stack_resource,
stack_user and signal_responder, and move
non-resources to engine/, such as iso_8601.py module.

Change-Id: Ic26c34cc8d34ca03ce674dc8c6ac32c10885b75f
Implements: blueprint reorganize-resources-code-structure
2015-03-10 18:07:46 +08:00

314 lines
12 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 oslo_serialization import jsonutils
from requests import exceptions
import six
from heat.common import exception
from heat.common.i18n import _
from heat.common import template_format
from heat.common import urlfetch
from heat.engine import attributes
from heat.engine import environment
from heat.engine import properties
from heat.engine.resources import stack_resource
from heat.engine import template
def generate_class(name, template_name, env):
data = TemplateResource.get_template_file(template_name, ('file',))
tmpl = template.Template(template_format.parse(data))
props, attrs = TemplateResource.get_schemas(tmpl, env.param_defaults)
cls = type(name, (TemplateResource,),
{'properties_schema': props,
'attributes_schema': attrs})
return cls
class TemplateResource(stack_resource.StackResource):
'''
A resource implemented by a nested stack.
This implementation passes resource properties as parameters to the nested
stack. Outputs of the nested stack are exposed as attributes of this
resource.
'''
def __init__(self, name, json_snippet, stack):
self._parsed_nested = None
self.stack = stack
self.validation_exception = None
tri = stack.env.get_resource_info(
json_snippet['Type'],
resource_name=name,
registry_type=environment.TemplateResourceInfo)
if tri is None:
self.validation_exception = ValueError(_(
'Only Templates with an extension of .yaml or '
'.template are supported'))
else:
self.template_name = tri.template_name
if tri.user_resource:
self.allowed_schemes = ('http', 'https')
else:
self.allowed_schemes = ('http', 'https', 'file')
# run Resource.__init__() so we can call self.nested()
self.properties_schema = {}
self.attributes_schema = {}
super(TemplateResource, self).__init__(name, json_snippet, stack)
self.resource_info = tri
if self.validation_exception is None:
self._generate_schema(self.t)
@staticmethod
def get_template_file(template_name, allowed_schemes):
try:
return urlfetch.get(template_name, allowed_schemes=allowed_schemes)
except (IOError, exceptions.RequestException) as r_exc:
args = {'name': template_name, 'exc': six.text_type(r_exc)}
msg = _('Could not fetch remote template '
'"%(name)s": %(exc)s') % args
raise exception.NotFound(msg_fmt=msg)
@staticmethod
def get_schemas(tmpl, param_defaults):
return ((properties.Properties.schema_from_params(
tmpl.param_schemata(param_defaults))),
(attributes.Attributes.schema_from_outputs(
tmpl[tmpl.OUTPUTS])))
def _generate_schema(self, definition):
self._parsed_nested = None
try:
tmpl = template.Template(self.child_template())
except (exception.NotFound, ValueError) as download_error:
self.validation_exception = download_error
tmpl = template.Template(
{"HeatTemplateFormatVersion": "2012-12-12"})
# re-generate the properties and attributes from the template.
self.properties_schema, self.attributes_schema = self.get_schemas(
tmpl, self.stack.env.param_defaults)
self.properties = definition.properties(self.properties_schema,
self.context)
self.attributes = attributes.Attributes(self.name,
self.attributes_schema,
self._resolve_attribute)
def child_params(self):
'''
:return: parameter values for our nested stack based on our properties
'''
params = {}
for pname, pval in iter(self.properties.props.items()):
if not pval.implemented():
continue
try:
val = self.properties[pname]
except ValueError:
if self.action == self.INIT:
prop = self.properties.props[pname]
val = prop.get_value(None)
else:
raise
if val is not None:
# take a list and create a CommaDelimitedList
if pval.type() == properties.Schema.LIST:
if len(val) == 0:
params[pname] = ''
elif isinstance(val[0], dict):
flattened = []
for (count, item) in enumerate(val):
for (ik, iv) in iter(item.items()):
mem_str = '.member.%d.%s=%s' % (count, ik, iv)
flattened.append(mem_str)
params[pname] = ','.join(flattened)
else:
params[pname] = ','.join(val)
else:
# for MAP, the JSON param takes either a collection or
# string, so just pass it on and let the param validate
# as appropriate
params[pname] = val
return params
def child_template(self):
if not self._parsed_nested:
self._parsed_nested = template_format.parse(self.template_data())
return self._parsed_nested
def implementation_signature(self):
self._generate_schema(self.t)
return super(TemplateResource, self).implementation_signature()
def template_data(self):
# we want to have the latest possible template.
# 1. look in files
# 2. try download
# 3. look in the db
reported_excp = None
t_data = self.stack.t.files.get(self.template_name)
if not t_data and self.template_name.endswith((".yaml", ".template")):
try:
t_data = self.get_template_file(self.template_name,
self.allowed_schemes)
except exception.NotFound as err:
reported_excp = err
if t_data is None:
if self.nested() is not None:
t_data = jsonutils.dumps(self.nested().t.t)
if t_data is not None:
self.stack.t.files[self.template_name] = t_data
return t_data
if reported_excp is None:
reported_excp = ValueError(_('Unknown error retrieving %s') %
self.template_name)
raise reported_excp
def _validate_against_facade(self, facade_cls):
facade_schemata = properties.schemata(facade_cls.properties_schema)
for n, fs in facade_schemata.items():
if fs.required and n not in self.properties_schema:
msg = (_("Required property %(n)s for facade %(type)s "
"missing in provider") % {'n': n, 'type': self.type()})
raise exception.StackValidationFailed(message=msg)
ps = self.properties_schema.get(n)
if (n in self.properties_schema and
(fs.allowed_param_prop_type() != ps.type)):
# Type mismatch
msg = (_("Property %(n)s type mismatch between facade %(type)s"
" (%(fs_type)s) and provider (%(ps_type)s)") % {
'n': n, 'type': self.type(),
'fs_type': fs.type, 'ps_type': ps.type})
raise exception.StackValidationFailed(message=msg)
for n, ps in self.properties_schema.items():
if ps.required and n not in facade_schemata:
# Required property for template not present in facade
msg = (_("Provider requires property %(n)s "
"unknown in facade %(type)s") % {
'n': n, 'type': self.type()})
raise exception.StackValidationFailed(message=msg)
for attr in facade_cls.attributes_schema:
if attr not in self.attributes_schema:
msg = (_("Attribute %(attr)s for facade %(type)s "
"missing in provider") % {
'attr': attr, 'type': self.type()})
raise exception.StackValidationFailed(message=msg)
def validate(self):
if self.validation_exception is not None:
msg = six.text_type(self.validation_exception)
raise exception.StackValidationFailed(message=msg)
try:
self.template_data()
except ValueError as ex:
msg = _("Failed to retrieve template data: %s") % ex
raise exception.StackValidationFailed(message=msg)
cri = self.stack.env.get_resource_info(
self.type(),
resource_name=self.name,
registry_type=environment.ClassResourceInfo)
# If we're using an existing resource type as a facade for this
# template, check for compatibility between the interfaces.
if cri is not None and not isinstance(self, cri.get_class()):
facade_cls = cri.get_class()
self._validate_against_facade(facade_cls)
return super(TemplateResource, self).validate()
def handle_adopt(self, resource_data=None):
return self.create_with_template(self.child_template(),
self.child_params(),
adopt_data=resource_data)
def handle_create(self):
return self.create_with_template(self.child_template(),
self.child_params())
def metadata_update(self, new_metadata=None):
'''
Refresh the metadata if new_metadata is None
'''
if new_metadata is None:
self.metadata_set(self.t.metadata())
def handle_update(self, json_snippet, tmpl_diff, prop_diff):
self._generate_schema(json_snippet)
return self.update_with_template(self.child_template(),
self.child_params())
def handle_delete(self):
return self.delete_nested()
def FnGetRefId(self):
if self.nested() is None:
return six.text_type(self.name)
if 'OS::stack_id' in self.nested().outputs:
return self.nested().output('OS::stack_id')
return self.nested().identifier().arn()
def FnGetAtt(self, key, *path):
stack = self.nested()
if stack is None:
return None
def _get_inner_resource(resource_name):
if self.nested() is not None:
try:
return self.nested()[resource_name]
except KeyError:
raise exception.ResourceNotFound(
resource_name=resource_name,
stack_name=self.nested().name)
def get_rsrc_attr(resource_name, *attr_path):
resource = _get_inner_resource(resource_name)
return resource.FnGetAtt(*attr_path)
def get_rsrc_id(resource_name):
resource = _get_inner_resource(resource_name)
return resource.FnGetRefId()
# first look for explicit resource.x.y
if key.startswith('resource.'):
npath = key.split(".", 2)[1:] + list(path)
if len(npath) > 1:
return get_rsrc_attr(*npath)
else:
return get_rsrc_id(*npath)
# then look for normal outputs
if key in stack.outputs:
return attributes.select_from_attribute(stack.output(key), path)
# otherwise the key must be wrong.
raise exception.InvalidTemplateAttribute(resource=self.name,
key=key)