Enable JS 2.0 (authenticated) extensions to work with classic notebook servers

jupyter_server/auth/identity.py

@@ -236,7 +236,8 @@ async def _get_user(self, handler: JupyterHandler) -> User | None:
  _token_user: User | None | Awaitable[User | None] = self.get_user_token(handler)
  if isinstance(_token_user, Awaitable):
  _token_user = await _token_user
- token_user: User | None = _token_user # need second variable name to collapse type
+ # need second variable name to collapse type
+ token_user: User | None = _token_user
  _cookie_user = self.get_user_cookie(handler)
  if isinstance(_cookie_user, Awaitable):
  _cookie_user = await _cookie_user

jupyter_server/base/handlers.py

@@ -251,9 +251,28 @@ def identity_provider(self):
  )
  from jupyter_server.auth import IdentityProvider
 
- # no identity provider set, load default
+ non_alphanum = re.compile(r"[^A-Za-z0-9]")
+ default_cookie_name = non_alphanum.sub("-", f"username-{self.request.host}")
+
+ # If there is no identity provider set, load the default. If using
+ # a classic notebook server, adding extensions that inherit
+ # from JupyterHandler will use a mix of new+old authentication log.
+ # Here, we construct an identity provider that works side-by-side
+ # and consistently with the old way that we handled auth in
+ # the classic server.
  self.settings["identity_provider"] = IdentityProvider(
- config=self.settings.get("config", None)
+ config=self.settings.get("config", None),
+ # For backwards compatibility, pass the token
+ # from the webapp settings.
+ token=self.settings.get("token", "<generated>"),
+ # Prefix the cookie name with "model-" to avoid colliding with
+ # the cookie set by the classic server.
+ # NOTE: This creates two cookies to authenticate the user
+ # (1) the token cookie and (2) the user model cookie.
+ cookie_name="model-" + self.settings.get("cookie_name", default_cookie_name),
+ cookie_options=self.settings.get("cookie_options", {}),
+ secure_cookie=self.settings.get("secure_cookie", None),
+ get_secure_cookie_kwargs=self.settings.get("get_secure_cookie_kwargs", {}),
  )
  return self.settings["identity_provider"]