diff --git a/heat/engine/attributes.py b/heat/engine/attributes.py index 4721cec534..d719a80b99 100644 --- a/heat/engine/attributes.py +++ b/heat/engine/attributes.py @@ -237,6 +237,34 @@ class Attributes(collections.Mapping): '\n\t'.join(six.itervalues(self))) +class DynamicSchemeAttributes(Attributes): + """The collection of attributes for resources without static attr scheme. + + The class defines collection of attributes for such entities as Resource + Group, Software Deployment and so on that doesn't have static attribute + scheme. The attribute scheme for such kind of resources can contain + attribute from attribute scheme (like other resources) and dynamic + attributes (nested stack attrs or API response attrs). + """ + + def __getitem__(self, key): + try: + # check if the value can be resolved with attributes + # in attributes schema (static attributes) + return super(DynamicSchemeAttributes, self).__getitem__(key) + except KeyError: + # ok, the attribute is not present in attribute scheme + # try to check the attributes dynamically + if key in self._resolved_values: + return self._resolved_values[key] + + value = self._resolver(key) + if value is not None: + self._resolved_values[key] = value + + return value + + def select_from_attribute(attribute_value, path): ''' Select an element from an attribute value. diff --git a/heat/engine/resource.py b/heat/engine/resource.py index 047ce883c9..c905a4d56e 100644 --- a/heat/engine/resource.py +++ b/heat/engine/resource.py @@ -182,6 +182,18 @@ class Resource(object): return super(Resource, cls).__new__(ResourceClass) + def _init_attributes(self): + """The method that defines attribute initialization for a resource. + + Some resource requires different initialization of resource attributes. + So they must override this method and return the initialized + attributes to the resource. + :return: resource attributes + """ + return attributes.Attributes(self.name, + self.attributes_schema, + self._resolve_all_attributes) + def __init__(self, name, definition, stack): def _validate_name(res_name): @@ -196,9 +208,7 @@ class Resource(object): self.t = definition self.reparse() self.attributes_schema.update(self.base_attributes_schema) - self.attributes = attributes.Attributes(self.name, - self.attributes_schema, - self._resolve_all_attributes) + self.attributes = self._init_attributes() self.abandon_in_progress = False diff --git a/heat/tests/common.py b/heat/tests/common.py index 99472022d2..5145a983fa 100644 --- a/heat/tests/common.py +++ b/heat/tests/common.py @@ -161,6 +161,8 @@ class HeatTestCase(testscenarios.WithScenarios, generic_rsrc.StackResourceType) resource._register_class('ResourceWithRestoreType', generic_rsrc.ResourceWithRestoreType) + resource._register_class('DynamicSchemaResource', + generic_rsrc.DynamicSchemaResource) def patchobject(self, obj, attr, **kwargs): mockfixture = self.useFixture(mockpatch.PatchObject(obj, attr, diff --git a/heat/tests/generic_resource.py b/heat/tests/generic_resource.py index ce0e0d0c2d..254b809044 100644 --- a/heat/tests/generic_resource.py +++ b/heat/tests/generic_resource.py @@ -263,3 +263,27 @@ class ResourceWithRestoreType(ResWithComplexPropsAndAttrs): value = data['resource_data']['a_string'] props['a_string'] = value return defn.freeze(properties=props) + + +class DynamicSchemaResource(resource.Resource): + """Resource with an attribute not registered in the attribute schema.""" + properties_schema = {} + + attributes_schema = { + 'stat_attr': attributes.Schema('A generic static attribute', + type=attributes.Schema.STRING), + } + + def _init_attributes(self): + # software deployment scheme is not static + # so return dynamic attributes for it + return attributes.DynamicSchemeAttributes( + self.name, self.attributes_schema, self._resolve_attribute) + + def _resolve_attribute(self, name): + if name == 'stat_attr': + return "static_attribute" + elif name == 'dynamic_attr': + return "dynamic_attribute" + else: + raise KeyError() diff --git a/heat/tests/test_attributes.py b/heat/tests/test_attributes.py index c32526016b..bf4d76a58a 100644 --- a/heat/tests/test_attributes.py +++ b/heat/tests/test_attributes.py @@ -16,8 +16,13 @@ import six from heat.engine import attributes from heat.engine import resources +from heat.engine import rsrc_defn +from heat.engine import stack from heat.engine import support +from heat.engine import template from heat.tests import common +from heat.tests import generic_resource +from heat.tests import utils class AttributeSchemaTest(common.HeatTestCase): @@ -243,3 +248,25 @@ class AttributesTypeTest(common.HeatTestCase): self.assertNotIn(msg, self.LOG.output) attribs._validate_type(attr, self.invalid_value) self.assertIn(msg, self.LOG.output) + + +class DynamicSchemeAttributeTest(common.HeatTestCase): + def setUp(self): + super(DynamicSchemeAttributeTest, self).setUp() + test_stack = stack.Stack( + utils.dummy_context(), 'test_stack', + template.Template.create_empty_template()) + snippet = rsrc_defn.ResourceDefinition('test_resource', + 'DynamicSchemaResource') + test_res = generic_resource.DynamicSchemaResource( + 'aresource', snippet, test_stack) + self.attrs = test_res.attributes + + def test_get_static_attribute(self): + self.assertEqual("static_attribute", self.attrs["stat_attr"]) + + def test_get_dynamic_attribute(self): + self.assertEqual("dynamic_attribute", self.attrs["dynamic_attr"]) + + def test_get_non_existing_attribute(self): + self.assertRaises(KeyError, self.attrs.__getitem__, "non_existing")