added v3

venv/lib/python3.11/site-packages/nacl/encoding.py

@@ -0,0 +1,105 @@
+# Copyright 2013 Donald Stufft and individual contributors
+#
+# 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.
+import base64
+import binascii
+from abc import ABCMeta, abstractmethod
+from typing import SupportsBytes, Type
+
+
+# TODO: when the minimum supported version of Python is 3.8, we can import
+# Protocol from typing, and replace Encoder with a Protocol instead.
+class _Encoder(metaclass=ABCMeta):
+    @staticmethod
+    @abstractmethod
+    def encode(data: bytes) -> bytes:
+        """Transform raw data to encoded data."""
+
+    @staticmethod
+    @abstractmethod
+    def decode(data: bytes) -> bytes:
+        """Transform encoded data back to raw data.
+
+        Decoding after encoding should be a no-op, i.e. `decode(encode(x)) == x`.
+        """
+
+
+# Functions that use encoders are passed a subclass of _Encoder, not an instance
+# (because the methods are all static). Let's gloss over that detail by defining
+# an alias for Type[_Encoder].
+Encoder = Type[_Encoder]
+
+
+class RawEncoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return data
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return data
+
+
+class HexEncoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return binascii.hexlify(data)
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return binascii.unhexlify(data)
+
+
+class Base16Encoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return base64.b16encode(data)
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return base64.b16decode(data)
+
+
+class Base32Encoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return base64.b32encode(data)
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return base64.b32decode(data)
+
+
+class Base64Encoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return base64.b64encode(data)
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return base64.b64decode(data)
+
+
+class URLSafeBase64Encoder(_Encoder):
+    @staticmethod
+    def encode(data: bytes) -> bytes:
+        return base64.urlsafe_b64encode(data)
+
+    @staticmethod
+    def decode(data: bytes) -> bytes:
+        return base64.urlsafe_b64decode(data)
+
+
+class Encodable:
+    def encode(self: SupportsBytes, encoder: Encoder = RawEncoder) -> bytes:
+        return encoder.encode(bytes(self))