Argument store added to updateEntityProperties.
This argument determines if an entity should be stored in the data model after its properties are updated.
It may be useful, for example, along with tasks (Task Queue API). One may want to make some modifications to an entity during execution of a task, but the developer is sure that at least one new task, which also wants to modify the entity, will be queued, so he or she can just update the entity without saving the changes to the data model, set the entity in memcache and the following task (which is to be executed very shortly) is to retrive the current entity from the memcache (without any expensive calls to the actual data model).
#!/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.
#
"""A wrapper around the generated Groc parser and lexer."""
import google
import antlr3
import GrocLexer
import GrocParser
class GrocException(Exception):
"""An error occurred while parsing the groc input string."""
class GrocLexerWithErrors(GrocLexer.GrocLexer):
"""An overridden Lexer that raises exceptions."""
def emitErrorMessage(self, msg):
"""Raise an exception if the input fails to parse correctly.
Overriding the default, which normally just prints a message to
stderr.
Arguments:
msg: the error message
Raises:
GrocException: always.
"""
raise GrocException(msg)
class GrocParserWithErrors(GrocParser.GrocParser):
"""An overridden Parser that raises exceptions."""
def emitErrorMessage(self, msg):
"""Raise an exception if the input fails to parse correctly.
Overriding the default, which normally just prints a message to
stderr.
Arguments:
msg: the error message
Raises:
GrocException: always.
"""
raise GrocException(msg)
def CreateParser(parse_string):
"""Creates a Groc Parser."""
input_string = antlr3.ANTLRStringStream(parse_string)
lexer = GrocLexerWithErrors(input_string)
tokens = antlr3.CommonTokenStream(lexer)
parser = GrocParserWithErrors(tokens)
return parser