Implement explicit methods to save and get OAuth2 token and secrets

flask_discord/_http.py

@@ -55,8 +55,14 @@ def user_id(self) -> typing.Union[int, None]:
         return session.get("DISCORD_USER_ID")
 
     @staticmethod
-    def _token_updater(token):
-        session["DISCORD_OAUTH2_TOKEN"] = token
+    @abc.abstractmethod
+    def save_authorization_token(token: dict):
+        raise NotImplementedError
+
+    @staticmethod
+    @abc.abstractmethod
+    def get_authorization_token() -> dict:
+        raise NotImplementedError
 
     def _fetch_token(self):
         discord = self._make_session(state=session.get("DISCORD_OAUTH2_STATE"))
@@ -87,7 +93,7 @@ def _make_session(self, token: str = None, state: str = None, scope: list = None
         """
         return OAuth2Session(
             client_id=self.client_id,
-            token=token or session.get("DISCORD_OAUTH2_TOKEN"),
+            token=token or self.get_authorization_token(),
             state=state or session.get("DISCORD_OAUTH2_STATE"),
             scope=scope,
             redirect_uri=self.redirect_uri,
@@ -96,7 +102,7 @@ def _make_session(self, token: str = None, state: str = None, scope: list = None
                 'client_secret': self.__client_secret,
             },
             auto_refresh_url=configs.DISCORD_TOKEN_URL,
-            token_updater=self._token_updater)
+            token_updater=self.save_authorization_token)
 
     def request(self, route: str, method="GET", data=None, oauth=True, **kwargs) -> typing.Union[dict, str]:
         """Sends HTTP request to provided route or discord endpoint.

flask_discord/client.py

@@ -82,6 +82,27 @@ def create_session(self, scope: list = None, prompt: bool = True, params: dict =
 
         return redirect(authorization_url)
 
+    @staticmethod
+    def save_authorization_token(token: dict):
+        """A staticmethod which saves a dict containing Discord OAuth2 token and other secrets to the user's cookies.
+        Meaning by default, it uses client side session handling.
+
+        Override this method if you want to handle the user's session server side. If this method is overridden then,
+        you must also override :py:meth:`flask_discord.DiscordOAuth2Session.get_authorization_token`.
+
+        """
+        session["DISCORD_OAUTH2_TOKEN"] = token
+
+    @staticmethod
+    def get_authorization_token() -> dict:
+        """A static method which returns a dict containing Discord OAuth2 token and other secrets which was saved
+        previously by `:py:meth:`flask_discord.DiscordOAuth2Session.save_authorization_token` from user's cookies.
+
+        You must override this method if you are implementing server side session handling.
+
+        """
+        return session.get("DISCORD_OAUTH2_TOKEN")
+
     def callback(self):
         """A method which should be always called after completing authorization code grant process
         usually in callback view.
@@ -92,7 +113,7 @@ def callback(self):
         if request.values.get("error"):
             return request.values["error"]
         token = self._fetch_token()
-        self._token_updater(token)
+        self.save_authorization_token(token)
 
     def revoke(self):
         """This method clears current discord token, state and all session data from flask

flask_discord/models/user.py

@@ -189,7 +189,7 @@ def add_to_guild(self, guild_id) -> dict:
 
         """
         try:
-            data = {"access_token": session["DISCORD_OAUTH2_TOKEN"]["access_token"]}
+            data = {"access_token": current_app.discord.get_authorization_token()["access_token"]}
         except KeyError:
             raise exceptions.Unauthorized
         return self._bot_request(f"/guilds/{guild_id}/members/{self.id}", method="PUT", json=data) or dict()