text: #    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 toscaparser.capabilities import Capability
  from toscaparser.common.exception import ExceptionCollector
  from toscaparser.common.exception import MissingRequiredFieldError
  from toscaparser.common.exception import UnknownFieldError
  from toscaparser.common.exception import ValidationError
  from toscaparser.elements.grouptype import GroupType
  from toscaparser.elements.interfaces import InterfacesDef
  from toscaparser.elements.nodetype import NodeType
  from toscaparser.elements.policytype import PolicyType
  from toscaparser.elements.relationshiptype import RelationshipType
  from toscaparser.properties import Property
  from toscaparser.unsupportedtype import UnsupportedType
  from toscaparser.utils.gettextutils import _
  
  
  class EntityTemplate(object):
      '''Base class for TOSCA templates.'''
  
      SECTIONS = (DERIVED_FROM, PROPERTIES, REQUIREMENTS,
                  INTERFACES, CAPABILITIES, TYPE, DESCRIPTION, DIRECTIVES,
                  ATTRIBUTES, ARTIFACTS, NODE_FILTER, COPY) = \
                 ('derived_from', 'properties', 'requirements', 'interfaces',
                  'capabilities', 'type', 'description', 'directives',
                  'attributes', 'artifacts', 'node_filter', 'copy')
      REQUIREMENTS_SECTION = (NODE, CAPABILITY, RELATIONSHIP, OCCURRENCES, NODE_FILTER) = \
                             ('node', 'capability', 'relationship',
                              'occurrences', 'node_filter')
      # Special key names
      SPECIAL_SECTIONS = (METADATA) = ('metadata')
  
      def __init__(self, name, template, entity_name, custom_def=None):
          self.name = name
          self.entity_tpl = template
          self.custom_def = custom_def
          self._validate_field(self.entity_tpl)
          type = self.entity_tpl.get('type')
          UnsupportedType.validate_type(type)
          if entity_name == 'node_type':
              self.type_definition = NodeType(type, custom_def) \
                  if type is not None else None
          if entity_name == 'relationship_type':
              relationship = template.get('relationship')
              type = None
              if relationship and isinstance(relationship, dict):
                  type = relationship.get('type')
              elif isinstance(relationship, str):
                  type = self.entity_tpl['relationship']
              else:
                  type = self.entity_tpl['type']
              UnsupportedType.validate_type(type)
              self.type_definition = RelationshipType(type,
                                                      None, custom_def)
          if entity_name == 'policy_type':
              if not type:
                  msg = (_('Policy definition of "%(pname)s" must have'
                         ' a "type" ''attribute.') % dict(pname=name))
                  ExceptionCollector.appendException(
                      ValidationError(msg))
              self.type_definition = PolicyType(type, custom_def)
          if entity_name == 'group_type':
              self.type_definition = GroupType(type, custom_def) \
                  if type is not None else None
          self._properties = None
          self._interfaces = None
          self._requirements = None
          self._capabilities = None
          self._artifacts = None
  
      @property
      def type(self):
          if self.type_definition:
              return self.type_definition.type
  
      @property
      def parent_type(self):
          if self.type_definition:
              return self.type_definition.parent_type
  
      @property
      def requirements(self):
          if self._requirements is None:
              self._requirements = self.type_definition.get_value(
                  self.REQUIREMENTS,
                  self.entity_tpl) or []
          return self._requirements
  
      def get_properties_objects(self):
          '''Return properties objects for this template.'''
          if self._properties is None:
              self._properties = self._create_properties()
          return self._properties
  
      def get_properties(self):
          '''Return a dictionary of property name-object pairs.'''
          return {prop.name: prop
                  for prop in self.get_properties_objects()}
  
      def get_property_value(self, name):
          '''Return the value of a given property name.'''
          props = self.get_properties()
          if props and name in props.keys():
              return props[name].value
  
      @property
      def interfaces(self):
          if self._interfaces is None:
              self._interfaces = self._create_interfaces()
          return self._interfaces
      
      @property
      def artifacts(self):
          if self._artifacts is None:
              self._artifacts = self._create_artifacts()
          return self._artifacts
  
      def get_capabilities_objects(self):
          '''Return capabilities objects for this template.'''
          if not self._capabilities:
              self._capabilities = self._create_capabilities()
          return self._capabilities
  
      def get_capabilities(self):
          '''Return a dictionary of capability name-object pairs.'''
          return {cap.name: cap
                  for cap in self.get_capabilities_objects()}
  
      def is_derived_from(self, type_str):
          '''Check if object inherits from the given type.
  
          Returns true if this object is derived from 'type_str'.
          False otherwise.
          '''
          if not self.type:
              return False
          elif self.type == type_str:
              return True
          elif self.parent_type:
              return self.parent_type.is_derived_from(type_str)
          else:
              return False
  
      def _create_capabilities(self):
          capability = []
          caps = self.type_definition.get_value(self.CAPABILITIES,
                                                self.entity_tpl, True)
          if caps:
              for name, props in caps.items():
                  capabilities = self.type_definition.get_capabilities()
                  if name in capabilities.keys():
                      c = capabilities[name]
                      properties = {}
                      # first use the definition default value
                      if c.properties:
                          for property_name in c.properties.keys():
                              prop_def = c.properties[property_name]
                              if 'default' in prop_def:
                                  properties[property_name] = prop_def['default']
                      # then update (if available) with the node properties
                      if 'properties' in props and props['properties']:
                          properties.update(props['properties'])
  
                      cap = Capability(name, properties, c, self.custom_def)
                      capability.append(cap)
          return capability
  
      def _validate_properties(self, template, entitytype):
          properties = entitytype.get_value(self.PROPERTIES, template)
          self._common_validate_properties(entitytype, properties)
  
      def _validate_capabilities(self):
          type_capabilities = self.type_definition.get_capabilities()
          allowed_caps = \
              type_capabilities.keys() if type_capabilities else []
          capabilities = self.type_definition.get_value(self.CAPABILITIES,
                                                        self.entity_tpl)
          if capabilities:
              self._common_validate_field(capabilities, allowed_caps,
                                          'capabilities')
              self._validate_capabilities_properties(capabilities)
  
      def _validate_capabilities_properties(self, capabilities):
          for cap, props in capabilities.items():
              capability = self.get_capability(cap)
              if not capability:
                  continue
              capabilitydef = capability.definition
              self._common_validate_properties(capabilitydef,
                                               props[self.PROPERTIES])
  
              # validating capability properties values
              for prop in self.get_capability(cap).get_properties_objects():
                  prop.validate()
  
                  # TODO(srinivas_tadepalli): temporary work around to validate
                  # default_instances until standardized in specification
                  if cap == "scalable" and prop.name == "default_instances":
                      prop_dict = props[self.PROPERTIES]
                      min_instances = prop_dict.get("min_instances")
                      max_instances = prop_dict.get("max_instances")
                      default_instances = prop_dict.get("default_instances")
                      if not (min_instances <= default_instances
                              <= max_instances):
                          err_msg = ('"properties" of template "%s": '
                                     '"default_instances" value is not between '
                                     '"min_instances" and "max_instances".' %
                                     self.name)
                          ExceptionCollector.appendException(
                              ValidationError(message=err_msg))
  
      def _common_validate_properties(self, entitytype, properties):
          allowed_props = []
          required_props = []
          for p in entitytype.get_properties_def_objects():
              allowed_props.append(p.name)
              # If property is 'required' and has no 'default' value then record
              if p.required and p.default is None:
                  required_props.append(p.name)
          # validate all required properties have values
          if properties:
              req_props_no_value_or_default = []
              self._common_validate_field(properties, allowed_props,
                                          'properties')
              # make sure it's not missing any property required by a tosca type
              for r in required_props:
                  if r not in properties.keys():
                      req_props_no_value_or_default.append(r)
              # Required properties found without value or a default value
              if req_props_no_value_or_default:
                  ExceptionCollector.appendException(
                      MissingRequiredFieldError(
                          what='"properties" of template "%s"' % self.name,
                          required=req_props_no_value_or_default))
          else:
              # Required properties in schema, but not in template
              if required_props:
                  ExceptionCollector.appendException(
                      MissingRequiredFieldError(
                          what='"properties" of template "%s"' % self.name,
                          required=required_props))
  
      def _validate_field(self, template):
          if not isinstance(template, dict):
              ExceptionCollector.appendException(
                  MissingRequiredFieldError(
                      what='Template "%s"' % self.name, required=self.TYPE))
          try:
              relationship = template.get('relationship')
              if relationship and not isinstance(relationship, str):
                  relationship[self.TYPE]
              elif isinstance(relationship, str):
                  template['relationship']
              else:
                  template[self.TYPE]
          except KeyError:
              ExceptionCollector.appendException(
                  MissingRequiredFieldError(
                      what='Template "%s"' % self.name, required=self.TYPE))
  
      def _common_validate_field(self, schema, allowedlist, section):
          for name in schema:
              if name not in allowedlist:
                  ExceptionCollector.appendException(
                      UnknownFieldError(
                          what=('"%(section)s" of template "%(nodename)s"'
                                % {'section': section, 'nodename': self.name}),
                          field=name))
  
      def _create_properties(self):
          props = []
          properties = self.type_definition.get_value(self.PROPERTIES,
                                                      self.entity_tpl) or {}
          for name, value in properties.items():
              props_def = self.type_definition.get_properties_def()
              if props_def and name in props_def:
                  prop = Property(name, value,
                                  props_def[name].schema, self.custom_def)
                  props.append(prop)
          for p in self.type_definition.get_properties_def_objects():
              if p.default is not None and p.name not in properties.keys():
                  prop = Property(p.name, p.default, p.schema, self.custom_def)
                  props.append(prop)
          return props
  
      def _create_interfaces(self):
          interfaces = []
          type_interfaces = None
          if isinstance(self.type_definition, RelationshipType):
              if isinstance(self.entity_tpl, dict):
                  if self.INTERFACES in self.entity_tpl:
                      type_interfaces = self.entity_tpl[self.INTERFACES]
                  else:
                      for rel_def, value in self.entity_tpl.items():
                          if rel_def != 'type':
                              rel_def = self.entity_tpl.get(rel_def)
                              rel = None
                              if isinstance(rel_def, dict):
                                  rel = rel_def.get('relationship')
                              if rel:
                                  if self.INTERFACES in rel:
                                      type_interfaces = rel[self.INTERFACES]
                                      break
          else:
              type_interfaces = self.type_definition.get_value(self.INTERFACES,
                                                               self.entity_tpl)
          if type_interfaces:
              for interface_type, value in type_interfaces.items():
                  for op, op_def in value.items():
                      iface = InterfacesDef(self.type_definition,
                                            interfacetype=interface_type,
                                            node_template=self,
                                            name=op,
                                            value=op_def)
                      interfaces.append(iface)
          return interfaces
  
      def _create_artifacts(self):
          artifacts = []
          type_artifacts = None
          if isinstance(self.type_definition, NodeType):
              type_artifacts = self.type_definition.get_value(self.ARTIFACTS,
                                                      self.entity_tpl)
          else:
              return None
          if type_artifacts:
              for artifact_type, value in type_artifacts.items():
                  artifacts.append({ 'name': artifact_type, **value})
                  # TODO: use the same approach of other entities
                  # for op, op_def in value.items():
                  #     iface = InterfacesDef(self.type_definition,
                  #                           interfacetype=artifact_type,
                  #                           node_template=self,
                  #                           name=op,
                  #                           value=op_def)
                  #     artifacts.append(iface)
          return artifacts
  
      def get_capability(self, name):
          """Provide named capability
  
          :param name: name of capability
          :return: capability object if found, None otherwise
          """
          caps = self.get_capabilities()
          if caps and name in caps.keys():
              return caps[name]
  