| # Copyright 2019 The gRPC authors. |
| # |
| # 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. |
| |
| from grpc._cython import cygrpc |
| |
| NoCompression = cygrpc.CompressionAlgorithm.none |
| Deflate = cygrpc.CompressionAlgorithm.deflate |
| Gzip = cygrpc.CompressionAlgorithm.gzip |
| |
| _METADATA_STRING_MAPPING = { |
| NoCompression: 'identity', |
| Deflate: 'deflate', |
| Gzip: 'gzip', |
| } |
| |
| |
| def _compression_algorithm_to_metadata_value(compression): |
| return _METADATA_STRING_MAPPING[compression] |
| |
| |
| def compression_algorithm_to_metadata(compression): |
| return (cygrpc.GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY, |
| _compression_algorithm_to_metadata_value(compression)) |
| |
| |
| def create_channel_option(compression): |
| return ((cygrpc.GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM, |
| int(compression)),) if compression else () |
| |
| |
| def augment_metadata(metadata, compression): |
| if not metadata and not compression: |
| return None |
| base_metadata = tuple(metadata) if metadata else () |
| compression_metadata = ( |
| compression_algorithm_to_metadata(compression),) if compression else () |
| return base_metadata + compression_metadata |
| |
| |
| __all__ = ( |
| "NoCompression", |
| "Deflate", |
| "Gzip", |
| ) |