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Diffstat (limited to '.venv/lib/python3.12/site-packages/grpc/aio/_metadata.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/grpc/aio/_metadata.py | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/grpc/aio/_metadata.py b/.venv/lib/python3.12/site-packages/grpc/aio/_metadata.py new file mode 100644 index 00000000..6303c175 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/grpc/aio/_metadata.py @@ -0,0 +1,137 @@ +# Copyright 2020 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. +"""Implementation of the metadata abstraction for gRPC Asyncio Python.""" +from collections import OrderedDict +from collections import abc +from typing import Any, Iterator, List, Optional, Tuple, Union + +MetadataKey = str +MetadataValue = Union[str, bytes] + + +class Metadata(abc.Collection): + """Metadata abstraction for the asynchronous calls and interceptors. + + The metadata is a mapping from str -> List[str] + + Traits + * Multiple entries are allowed for the same key + * The order of the values by key is preserved + * Getting by an element by key, retrieves the first mapped value + * Supports an immutable view of the data + * Allows partial mutation on the data without recreating the new object from scratch. + """ + + def __init__(self, *args: Tuple[MetadataKey, MetadataValue]) -> None: + self._metadata = OrderedDict() + for md_key, md_value in args: + self.add(md_key, md_value) + + @classmethod + def from_tuple(cls, raw_metadata: tuple): + if raw_metadata: + return cls(*raw_metadata) + return cls() + + def add(self, key: MetadataKey, value: MetadataValue) -> None: + self._metadata.setdefault(key, []) + self._metadata[key].append(value) + + def __len__(self) -> int: + """Return the total number of elements that there are in the metadata, + including multiple values for the same key. + """ + return sum(map(len, self._metadata.values())) + + def __getitem__(self, key: MetadataKey) -> MetadataValue: + """When calling <metadata>[<key>], the first element of all those + mapped for <key> is returned. + """ + try: + return self._metadata[key][0] + except (ValueError, IndexError) as e: + raise KeyError("{0!r}".format(key)) from e + + def __setitem__(self, key: MetadataKey, value: MetadataValue) -> None: + """Calling metadata[<key>] = <value> + Maps <value> to the first instance of <key>. + """ + if key not in self: + self._metadata[key] = [value] + else: + current_values = self.get_all(key) + self._metadata[key] = [value, *current_values[1:]] + + def __delitem__(self, key: MetadataKey) -> None: + """``del metadata[<key>]`` deletes the first mapping for <key>.""" + current_values = self.get_all(key) + if not current_values: + raise KeyError(repr(key)) + self._metadata[key] = current_values[1:] + + def delete_all(self, key: MetadataKey) -> None: + """Delete all mappings for <key>.""" + del self._metadata[key] + + def __iter__(self) -> Iterator[Tuple[MetadataKey, MetadataValue]]: + for key, values in self._metadata.items(): + for value in values: + yield (key, value) + + def keys(self) -> abc.KeysView: + return abc.KeysView(self) + + def values(self) -> abc.ValuesView: + return abc.ValuesView(self) + + def items(self) -> abc.ItemsView: + return abc.ItemsView(self) + + def get( + self, key: MetadataKey, default: MetadataValue = None + ) -> Optional[MetadataValue]: + try: + return self[key] + except KeyError: + return default + + def get_all(self, key: MetadataKey) -> List[MetadataValue]: + """For compatibility with other Metadata abstraction objects (like in Java), + this would return all items under the desired <key>. + """ + return self._metadata.get(key, []) + + def set_all(self, key: MetadataKey, values: List[MetadataValue]) -> None: + self._metadata[key] = values + + def __contains__(self, key: MetadataKey) -> bool: + return key in self._metadata + + def __eq__(self, other: Any) -> bool: + if isinstance(other, self.__class__): + return self._metadata == other._metadata + if isinstance(other, tuple): + return tuple(self) == other + return NotImplemented # pytype: disable=bad-return-type + + def __add__(self, other: Any) -> "Metadata": + if isinstance(other, self.__class__): + return Metadata(*(tuple(self) + tuple(other))) + if isinstance(other, tuple): + return Metadata(*(tuple(self) + other)) + return NotImplemented # pytype: disable=bad-return-type + + def __repr__(self) -> str: + view = tuple(self) + return "{0}({1!r})".format(self.__class__.__name__, view) |