Merge pull request #14 from rwth-iat/http_api/improve_base64url_decoding

adapter.http: fix base64 decoding without padding

basyx/aas/adapter/http.py

@@ -376,7 +376,11 @@ def to_url(self, value: model.Identifier) -> str:
  def to_python(self, value: str) -> model.Identifier:
  value = super().to_python(value)
  try:
- decoded = base64.urlsafe_b64decode(super().to_python(value)).decode(self.encoding)
+ # If the requester omits the base64 padding, an exception will be raised.
+ # However, Python doesn't complain about too much padding,
+ # thus we simply always append two padding characters (==).
+ # See also: https://stackoverflow.com/a/49459036/4780052
+ decoded = base64.urlsafe_b64decode(super().to_python(value) + "==").decode(self.encoding)
  except binascii.Error:
  raise BadRequest(f"Encoded identifier {value} is invalid base64url!")
  except UnicodeDecodeError: