Source code for heat.engine.translation

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#         http://www.apache.org/licenses/LICENSE-2.0
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#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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import six

from oslo_utils import encodeutils

from heat.common import exception
from heat.common.i18n import _
from heat.engine.cfn import functions as cfn_funcs
from heat.engine import function
from heat.engine.hot import functions as hot_funcs
from heat.engine import properties


[docs]class TranslationRule(object): """Translating mechanism one properties to another. Mechanism uses list of rules, each defines by this class, and can be executed. Working principe: during resource creating after properties defining resource take list of rules, specified by method translation_rules, which should be overloaded for each resource, if it's needed, and execute each rule using translate_properties method. Next operations are allowed: - ADD. This rule allows to add some value to list-type properties. Only list-type values can be added to such properties. Using for other cases is prohibited and will be returned with error. - REPLACE. This rule allows to replace some property value to another. Used for all types of properties. Note, that if property has list type, then value will be replaced for all elements of list, where it needed. If element in such property must be replaced by value of another element of this property, value_name must be defined. - DELETE. This rule allows to delete some property. If property has list type, then deleting affects value in all list elements. - RESOLVE. This rule allows to resolve some property using client and the finder function. Finders may require an additional entity key. """ RULE_KEYS = (ADD, REPLACE, DELETE, RESOLVE) = ('Add', 'Replace', 'Delete', 'Resolve') def __init__(self, properties, rule, translation_path, value=None, value_name=None, value_path=None, client_plugin=None, finder=None, entity=None, custom_value_path=None): """Add new rule for translating mechanism. :param properties: properties of resource :param rule: rule from RULE_KEYS :param translation_path: list with path to property, which value will be affected in rule. :param value: value which will be involved in rule :param value_name: value_name which used for replacing properties inside list-type properties. :param value_path: path to value, which should be used for translation. :param client_plugin: client plugin that would be used to resolve :param finder: finder method of the client plugin :param entity: some generic finders require an entity to resolve ex. neutron finder function. :param custom_value_path: list-type value path to translate property, which has no schema. """ self.properties = properties self.rule = rule self.translation_path = translation_path self.value = value or None self.value_name = value_name self.value_path = value_path self.client_plugin = client_plugin self.finder = finder self.entity = entity self.custom_value_path = custom_value_path self.validate()
[docs] def validate(self): if self.rule not in self.RULE_KEYS: raise ValueError(_('There is no rule %(rule)s. List of allowed ' 'rules is: %(rules)s.') % { 'rule': self.rule, 'rules': ', '.join(self.RULE_KEYS)}) elif not isinstance(self.properties, properties.Properties): raise ValueError(_('Properties must be Properties type. ' 'Found %s.') % type(self.properties)) elif not isinstance(self.translation_path, list): raise ValueError(_('translation_path should be a list with path ' 'instead of %s.') % type(self.translation_path)) elif len(self.translation_path) == 0: raise ValueError(_('translation_path must be non-empty list with ' 'path.')) elif (self.rule == self.ADD and ((self.value is not None) == (self.value_name is not None))): raise ValueError(_('Either value or value_name should be ' 'specified for rule Add.')) elif (self.rule == self.ADD and self.value is not None and not isinstance(self.value, list)): raise ValueError(_('value must be list type when rule is Add.')) elif (self.rule == self.RESOLVE and not (self.client_plugin or self.finder)): raise ValueError(_('client_plugin and finder should be specified ' 'for Resolve rule'))
[docs] def execute_rule(self, client_resolve=True): try: self._prepare_data(self.properties.data, self.translation_path, self.properties.props) if self.value_path: if self.custom_value_path: self.value_path.extend(self.custom_value_path) self._prepare_data(self.properties.data, self.value_path, self.properties.props) (value_key, value_data) = self.translate_property(self.value_path, self.properties.data, return_value=True) value = (value_data[value_key] if value_data and value_data.get(value_key) else self.value) else: (value_key, value_data) = None, None value = self.value except AttributeError: return self.translate_property(self.translation_path, self.properties.data, value=value, value_data=value_data, value_key=value_key, client_resolve=client_resolve)
def _prepare_data(self, data, path, props): def get_props(props, key): props = props.get(key) if props.schema.schema is not None: keys = list(props.schema.schema) schemata = dict((k, props.schema.schema[k]) for k in keys) props = dict((k, properties.Property(s, k)) for k, s in schemata.items()) if set(props.keys()) == set('*'): return get_props(props, '*') return props if not path: return current_key = path[0] if data.get(current_key) is None: if (self.rule in (TranslationRule.DELETE, TranslationRule.RESOLVE) or (self.rule == TranslationRule.REPLACE and self.value_name is not None)): return data_type = props.get(current_key).type() if data_type == properties.Schema.LIST: data[current_key] = [] if data_type == properties.Schema.MAP: data[current_key] = {} return data[current_key] = self._resolve_param(data.get(current_key)) if isinstance(data[current_key], list): for item in data[current_key]: self._prepare_data(item, path[1:], get_props(props, current_key)) elif isinstance(data[current_key], dict): self._prepare_data(data[current_key], path[1:], get_props(props, current_key)) def _exec_action(self, key, data, value=None, value_key=None, value_data=None, client_resolve=True): if self.rule == TranslationRule.ADD: self._exec_add(key, data, value) elif self.rule == TranslationRule.REPLACE: self._exec_replace(key, data, value_key, value_data, value) elif self.rule == TranslationRule.RESOLVE and client_resolve: self._exec_resolve(key, data) elif self.rule == TranslationRule.DELETE: self._exec_delete(key, data) def _resolve_param(self, param): """Check whether given item is param and resolve, if it is.""" if isinstance(param, (hot_funcs.GetParam, cfn_funcs.ParamRef)): try: return function.resolve(param) except exception.UserParameterMissing as ex: # We can't resolve parameter now. Abort translation. err_msg = encodeutils.exception_to_unicode(ex) raise AttributeError( _('Can not resolve parameter ' 'due to: %s') % err_msg) elif isinstance(param, list): return [self._resolve_param(param_item) for param_item in param] else: return param
[docs] def resolve_custom_value_path(self, translation_data, translation_key): new_value = translation_data[self.value_name] for key in self.custom_value_path[:-1]: if isinstance(new_value, (list, six.string_types)): raise ValueError( _('Incorrectly specified custom_value_path - ' 'cannot pull out required value from ' 'data of %s type.') % type(new_value)) if new_value.get(key) is None: return new_value = self._resolve_param(new_value[key]) resolved_value = self._resolve_param( new_value.get(self.custom_value_path[-1])) if resolved_value is None: return if self.rule == self.REPLACE: translation_data[translation_key] = resolved_value del new_value[self.custom_value_path[-1]] elif self.rule == self.ADD: if isinstance(resolved_value, list): translation_data[translation_key].extend(resolved_value) else: translation_data[translation_key].append(resolved_value)
[docs] def translate_property(self, path, data, return_value=False, value=None, value_data=None, value_key=None, client_resolve=True): if isinstance(data, function.Function): if return_value: raise AttributeError('No chance to translate value due to ' 'value is function. Skip translation.') return current_key = path[0] if len(path) <= 1: if return_value: return current_key, data else: self._exec_action(current_key, data, value=value, value_data=value_data, value_key=value_key, client_resolve=client_resolve) return if data.get(current_key) is None: return elif isinstance(data[current_key], list): for item in data[current_key]: if return_value: # Until there's no reasonable solution for cases of using # one list for value and another list for destination, # error would be raised. msg = _('Cannot use value_path for properties inside ' 'list-type properties') raise ValueError(msg) else: self.translate_property(path[1:], item, return_value=return_value, value=value, value_data=value_data, value_key=value_key, client_resolve=client_resolve) else: return self.translate_property(path[1:], data[current_key], return_value=return_value, value=value, value_data=value_data, value_key=value_key, client_resolve=client_resolve)
def _exec_add(self, translation_key, translation_data, value): if not isinstance(translation_data[translation_key], list): raise ValueError(_('Add rule must be used only for ' 'lists.')) if value is not None: translation_data[translation_key].extend(value) elif (self.value_name is not None and translation_data.get(self.value_name) is not None): if self.custom_value_path: self.resolve_custom_value_path(translation_data, translation_key) elif isinstance(translation_data[self.value_name], list): translation_data[translation_key].extend( translation_data[self.value_name]) else: translation_data[translation_key].append( translation_data[self.value_name]) def _exec_replace(self, translation_key, translation_data, value_key, value_data, value): value_ind = None if translation_data and translation_data.get(translation_key): if value_data and value_data.get(value_key): value_ind = value_key elif translation_data.get(self.value_name) is not None: value_ind = self.value_name if self.custom_value_path is not None: data = translation_data.get(self.value_name) for key in self.custom_value_path: data = data.get(key) if data is None: value_ind = None break if value_ind is not None: raise exception.ResourcePropertyConflict(props=[translation_key, value_ind]) if value is not None: translation_data[translation_key] = value elif (self.value_name is not None and translation_data.get(self.value_name) is not None): if self.custom_value_path: self.resolve_custom_value_path(translation_data, translation_key) else: translation_data[ translation_key] = translation_data[self.value_name] del translation_data[self.value_name] # If value defined with value_path, need to delete value_path # property data after it's replacing. if value_data and value_data.get(value_key): del value_data[value_key] def _exec_resolve(self, translation_key, translation_data): def resolve_and_find(translation_value): if isinstance(translation_value, hot_funcs.GetResource): return if isinstance(translation_value, function.Function): translation_value = function.resolve(translation_value) if translation_value: if isinstance(translation_value, list): resolved_value = [] for item in translation_value: resolved_value.append(resolve_and_find(item)) return resolved_value finder = getattr(self.client_plugin, self.finder) if self.entity: value = finder(self.entity, translation_value) else: value = finder(translation_value) return value if isinstance(translation_data, list): for item in translation_data: translation_value = item.get(translation_key) resolved_value = resolve_and_find(translation_value) if resolved_value is not None: item[translation_key] = resolved_value else: translation_value = translation_data.get(translation_key) resolved_value = resolve_and_find(translation_value) if resolved_value is not None: translation_data[translation_key] = resolved_value def _exec_delete(self, translation_key, translation_data): if isinstance(translation_data, list): for item in translation_data: if item.get(translation_key) is not None: del item[translation_key] else: del translation_data[translation_key]

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