Introduce dynamic scope_path regexps
Instead of relying on scope_path's being "one slash deep", we should
instead allow for either:
1. scope_paths that have a pre-defined depth
2. scope_paths that can be arbitrarily deep
We achieve 1 by setting an entities scope_logic to another logic
module. We then recursively call getScopeDepth until we get to the
topmost entity (that is, an unscoped entity).
A little different is the solution to 2, since some entities can have
an arbitrarily deep scope (such as Documents), we need to have some
way of signaling this to getScopePattern. A clean solution is to
return None, rather than a number. If None is returned, the
SCOPE_PATH_ARG_PATTERN is returned as regexp instead, which will
match an arbitrarily deeply nested scope.
The solution for 2 requires that we return None somewhere in the
scope_logic chain, the most straight forward method to do so is to
override getScopeDepth anywhere such a scope is needed and make it
return None. A more elegant solution however, is to set the
scope_logic to that module in all entities that require it.
Patch by: Sverre Rabbelier
#!/usr/bin/env python
#
# Copyright 2007 Google Inc.
#
# 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 Python datastore admin API for managing indices and schemas.
"""
from google.appengine.api import api_base_pb
from google.appengine.api import apiproxy_stub_map
from google.appengine.api import datastore
from google.appengine.api import datastore_errors
from google.appengine.api import datastore_types
from google.appengine.datastore import datastore_index
from google.appengine.datastore import datastore_pb
from google.appengine.runtime import apiproxy_errors
from google.appengine.datastore import entity_pb
_DIRECTION_MAP = {
'asc': entity_pb.Index_Property.ASCENDING,
'ascending': entity_pb.Index_Property.ASCENDING,
'desc': entity_pb.Index_Property.DESCENDING,
'descending': entity_pb.Index_Property.DESCENDING,
}
def GetSchema(_app=None):
"""Infers an app's schema from the entities in the datastore.
Note that the PropertyValue PBs in the returned EntityProtos are empty
placeholders, so they may cause problems if you try to convert them to
python values with e.g. datastore_types. In particular, user values will
throw UserNotFoundError because their email and auth domain fields will be
empty.
Returns:
list of entity_pb.EntityProto, with kind and property names and types
"""
req = api_base_pb.StringProto()
req.set_value(datastore_types.ResolveAppId(_app))
resp = datastore_pb.Schema()
_Call('GetSchema', req, resp)
return resp.kind_list()
def GetIndices(_app=None):
"""Fetches all composite indices in the datastore for this app.
Returns:
list of entity_pb.CompositeIndex
"""
req = api_base_pb.StringProto()
req.set_value(datastore_types.ResolveAppId(_app))
resp = datastore_pb.CompositeIndices()
try:
apiproxy_stub_map.MakeSyncCall('datastore_v3', 'GetIndices', req, resp)
except apiproxy_errors.ApplicationError, err:
raise datastore._ToDatastoreError(err)
return resp.index_list()
def CreateIndex(index):
"""Creates a new composite index in the datastore for this app.
Args:
index: entity_pb.CompositeIndex
Returns:
int, the id allocated to the index
"""
resp = api_base_pb.Integer64Proto()
_Call('CreateIndex', index, resp)
return resp.value()
def UpdateIndex(index):
"""Updates an index's status. The entire index definition must be present.
Args:
index: entity_pb.CompositeIndex
"""
_Call('UpdateIndex', index, api_base_pb.VoidProto())
def DeleteIndex(index):
"""Deletes an index. The entire index definition must be present.
Args:
index: entity_pb.CompositeIndex
"""
_Call('DeleteIndex', index, api_base_pb.VoidProto())
def _Call(call, req, resp):
"""Generic method for making a datastore API call.
Args:
call: string, the name of the RPC call
req: the request PB. if the app_id field is not set, it defaults to the
local app.
resp: the response PB
"""
if hasattr(req, 'app_id'):
req.set_app_id(datastore_types.ResolveAppId(req.app_id(), 'req.app_id()'))
try:
apiproxy_stub_map.MakeSyncCall('datastore_v3', call, req, resp)
except apiproxy_errors.ApplicationError, err:
raise datastore._ToDatastoreError(err)
def IndexDefinitionToProto(app_id, index_definition):
"""Transform individual Index definition to protocol buffer.
Args:
app_id: Application id for new protocol buffer CompositeIndex.
index_definition: datastore_index.Index object to transform.
Returns:
New entity_pb.CompositeIndex with default values set and index
information filled in.
"""
proto = entity_pb.CompositeIndex()
proto.set_app_id(app_id)
proto.set_id(0)
proto.set_state(entity_pb.CompositeIndex.WRITE_ONLY)
definition_proto = proto.mutable_definition()
definition_proto.set_entity_type(index_definition.kind)
definition_proto.set_ancestor(index_definition.ancestor)
if index_definition.properties is not None:
for prop in index_definition.properties:
prop_proto = definition_proto.add_property()
prop_proto.set_name(prop.name)
prop_proto.set_direction(_DIRECTION_MAP[prop.direction])
return proto
def IndexDefinitionsToProtos(app_id, index_definitions):
"""Transform multiple index definitions to composite index records
Args:
app_id: Application id for new protocol buffer CompositeIndex.
index_definition: A list of datastore_index.Index objects to transform.
Returns:
A list of tranformed entity_pb.Compositeindex entities with default values
set and index information filled in.
"""
return [IndexDefinitionToProto(app_id, index)
for index in index_definitions]
def ProtoToIndexDefinition(proto):
"""Transform individual index protocol buffer to index definition.
Args:
proto: An instance of entity_pb.CompositeIndex to transform.
Returns:
A new instance of datastore_index.Index.
"""
properties = []
proto_index = proto.definition()
for prop_proto in proto_index.property_list():
prop_definition = datastore_index.Property(name=prop_proto.name())
if prop_proto.direction() == entity_pb.Index_Property.DESCENDING:
prop_definition.direction = 'descending'
properties.append(prop_definition)
index = datastore_index.Index(kind=proto_index.entity_type(),
properties=properties)
if proto_index.ancestor():
index.ancestor = True
return index
def ProtosToIndexDefinitions(protos):
"""Transform multiple index protocol buffers to index definitions.
Args:
A list of entity_pb.Index records.
"""
return [ProtoToIndexDefinition(definition) for definition in protos]