54 lines
2.3 KiB
Python
54 lines
2.3 KiB
Python
|
# Copyright 2018 Google LLC
|
||
|
|
#
|
||
|
|
# 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
|
||
|
|
#
|
||
|
|
# https://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.
|
||
|
|
|
||
|
|
|
||
|
|
class MessageRule:
|
||
|
|
"""A marshal for converting between a descriptor and proto.Message."""
|
||
|
|
|
||
|
|
def __init__(self, descriptor: type, wrapper: type):
|
||
|
|
self._descriptor = descriptor
|
||
|
|
self._wrapper = wrapper
|
||
|
|
|
||
|
|
def to_python(self, value, *, absent: bool = None):
|
||
|
|
if isinstance(value, self._descriptor):
|
||
|
|
return self._wrapper.wrap(value)
|
||
|
|
return value
|
||
|
|
|
||
|
|
def to_proto(self, value):
|
||
|
|
if isinstance(value, self._wrapper):
|
||
|
|
return self._wrapper.pb(value)
|
||
|
|
if isinstance(value, dict) and not self.is_map:
|
||
|
|
# We need to use the wrapper's marshaling to handle
|
||
|
|
# potentially problematic nested messages.
|
||
|
|
try:
|
||
|
|
# Try the fast path first.
|
||
|
|
return self._descriptor(**value)
|
||
|
|
except (TypeError, ValueError, AttributeError) as ex:
|
||
|
|
# If we have a TypeError, ValueError or AttributeError,
|
||
|
|
# try the slow path in case the error
|
||
|
|
# was:
|
||
|
|
# - an int64/string issue.
|
||
|
|
# - a missing key issue in case a key only exists with a `_` suffix.
|
||
|
|
# See related issue: https://github.com/googleapis/python-api-core/issues/227.
|
||
|
|
# - a missing key issue due to nested struct. See: https://github.com/googleapis/proto-plus-python/issues/424.
|
||
|
|
# - a missing key issue due to nested duration. See: https://github.com/googleapis/google-cloud-python/issues/13350.
|
||
|
|
return self._wrapper(value)._pb
|
||
|
|
return value
|
||
|
|
|
||
|
|
@property
|
||
|
|
def is_map(self):
|
||
|
|
"""Return True if the descriptor is a map entry, False otherwise."""
|
||
|
|
desc = self._descriptor.DESCRIPTOR
|
||
|
|
return desc.has_options and desc.GetOptions().map_entry
|