| #!/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. |
| # |
| |
| |
| """Provides a container for DescriptorProtos.""" |
| |
| |
| |
| |
| class Error(Exception): |
| pass |
| |
| |
| class DescriptorDatabaseConflictingDefinitionError(Error): |
| """Raised when a proto is added with the same name & different descriptor.""" |
| |
| |
| class DescriptorDatabase(object): |
| """A container accepting FileDescriptorProtos and maps DescriptorProtos.""" |
| |
| def __init__(self): |
| self._file_desc_protos_by_file = {} |
| self._file_desc_protos_by_symbol = {} |
| |
| def Add(self, file_desc_proto): |
| """Adds the FileDescriptorProto and its types to this database. |
| |
| Args: |
| file_desc_proto: The FileDescriptorProto to add. |
| Raises: |
| DescriptorDatabaseException: if an attempt is made to add a proto |
| with the same name but different definition than an exisiting |
| proto in the database. |
| """ |
| proto_name = file_desc_proto.name |
| if proto_name not in self._file_desc_protos_by_file: |
| self._file_desc_protos_by_file[proto_name] = file_desc_proto |
| elif self._file_desc_protos_by_file[proto_name] != file_desc_proto: |
| raise DescriptorDatabaseConflictingDefinitionError( |
| '%s already added, but with different descriptor.' % proto_name) |
| |
| package = file_desc_proto.package |
| for message in file_desc_proto.message_type: |
| self._file_desc_protos_by_symbol.update( |
| (name, file_desc_proto) for name in _ExtractSymbols(message, package)) |
| for enum in file_desc_proto.enum_type: |
| self._file_desc_protos_by_symbol[ |
| '.'.join((package, enum.name))] = file_desc_proto |
| |
| def FindFileByName(self, name): |
| """Finds the file descriptor proto by file name. |
| |
| Typically the file name is a relative path ending to a .proto file. The |
| proto with the given name will have to have been added to this database |
| using the Add method or else an error will be raised. |
| |
| Args: |
| name: The file name to find. |
| |
| Returns: |
| The file descriptor proto matching the name. |
| |
| Raises: |
| KeyError if no file by the given name was added. |
| """ |
| |
| return self._file_desc_protos_by_file[name] |
| |
| def FindFileContainingSymbol(self, symbol): |
| """Finds the file descriptor proto containing the specified symbol. |
| |
| The symbol should be a fully qualified name including the file descriptor's |
| package and any containing messages. Some examples: |
| |
| 'some.package.name.Message' |
| 'some.package.name.Message.NestedEnum' |
| |
| The file descriptor proto containing the specified symbol must be added to |
| this database using the Add method or else an error will be raised. |
| |
| Args: |
| symbol: The fully qualified symbol name. |
| |
| Returns: |
| The file descriptor proto containing the symbol. |
| |
| Raises: |
| KeyError if no file contains the specified symbol. |
| """ |
| |
| return self._file_desc_protos_by_symbol[symbol] |
| |
| |
| def _ExtractSymbols(desc_proto, package): |
| """Pulls out all the symbols from a descriptor proto. |
| |
| Args: |
| desc_proto: The proto to extract symbols from. |
| package: The package containing the descriptor type. |
| |
| Yields: |
| The fully qualified name found in the descriptor. |
| """ |
| |
| message_name = '.'.join((package, desc_proto.name)) |
| yield message_name |
| for nested_type in desc_proto.nested_type: |
| for symbol in _ExtractSymbols(nested_type, message_name): |
| yield symbol |
| for enum_type in desc_proto.enum_type: |
| yield '.'.join((message_name, enum_type.name)) |