JezK
Edit File: url_safe.py
import typing as _t import zlib from ._json import _CompactJSON from .encoding import base64_decode from .encoding import base64_encode from .exc import BadPayload from .serializer import Serializer from .timed import TimedSerializer class URLSafeSerializerMixin(Serializer): """Mixed in with a regular serializer it will attempt to zlib compress the string to make it shorter if necessary. It will also base64 encode the string so that it can safely be placed in a URL. """ default_serializer = _CompactJSON def load_payload( self, payload: bytes, *args: _t.Any, serializer: _t.Optional[_t.Any] = None, **kwargs: _t.Any, ) -> _t.Any: decompress = False if payload.startswith(b"."): payload = payload[1:] decompress = True try: json = base64_decode(payload) except Exception as e: raise BadPayload( "Could not base64 decode the payload because of an exception", original_error=e, ) from e if decompress: try: json = zlib.decompress(json) except Exception as e: raise BadPayload( "Could not zlib decompress the payload before decoding the payload", original_error=e, ) from e return super().load_payload(json, *args, **kwargs) def dump_payload(self, obj: _t.Any) -> bytes: json = super().dump_payload(obj) is_compressed = False compressed = zlib.compress(json) if len(compressed) < (len(json) - 1): json = compressed is_compressed = True base64d = base64_encode(json) if is_compressed: base64d = b"." + base64d return base64d class URLSafeSerializer(URLSafeSerializerMixin, Serializer): """Works like :class:`.Serializer` but dumps and loads into a URL safe string consisting of the upper and lowercase character of the alphabet as well as ``'_'``, ``'-'`` and ``'.'``. """ class URLSafeTimedSerializer(URLSafeSerializerMixin, TimedSerializer): """Works like :class:`.TimedSerializer` but dumps and loads into a URL safe string consisting of the upper and lowercase character of the alphabet as well as ``'_'``, ``'-'`` and ``'.'``. """