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 ``'.'``.
|
"""
|
