Fix express module bookmarking

Author: schloerke

shiny/express/_stub_session.py

@@ -149,8 +149,14 @@ def download(
 
 class BookmarkExpressStub(Bookmark):
 
+    def __init__(self, root_session: ExpressStubSession) -> None:
+        super().__init__(root_session)
+        self._proxy_exclude_fns = []
+
     def _get_bookmark_exclude(self) -> list[str]:
-        raise NotImplementedError("Please call this only from a real session object")
+        raise NotImplementedError(
+            "Please call `._get_bookmark_exclude()` only from a real session object"
+        )
 
     def on_bookmark(
         self,
@@ -159,18 +165,26 @@ def on_bookmark(
             | Callable[[ShinySaveState], Awaitable[None]]
         ),
     ) -> None:
-        raise NotImplementedError("Please call this only from a real session object")
+        raise NotImplementedError(
+            "Please call `.on_bookmark()` only from a real session object"
+        )
 
     def on_bookmarked(
         self,
         callback: Callable[[str], None] | Callable[[str], Awaitable[None]],
     ) -> None:
-        raise NotImplementedError("Please call this only from a real session object")
+        raise NotImplementedError(
+            "Please call `.on_bookmarked()` only from a real session object"
+        )
 
     async def update_query_string(
         self, query_string: str, mode: Literal["replace", "push"] = "replace"
     ) -> None:
-        raise NotImplementedError("Please call this only from a real session object")
+        raise NotImplementedError(
+            "Please call `.update_query_string()` only from a real session object"
+        )
 
     async def do_bookmark(self) -> None:
-        raise NotImplementedError("Please call this only from a real session object")
+        raise NotImplementedError(
+            "Please call `.do_bookmark()` only from a real session object"
+        )

shiny/session/_session.py

@@ -428,7 +428,8 @@ def __init__(self, root_session: Session, ns: ResolvedId):
         async def scoped_on_bookmark(root_state: ShinySaveState) -> None:
             return await self._scoped_on_bookmark(root_state)
 
-        self._root_bookmark.on_bookmark(scoped_on_bookmark)
+        if isinstance(self._root_session, BookmarkApp):
+            self._root_bookmark.on_bookmark(scoped_on_bookmark)
 
         # TODO: Barret - Implement restore scoped state!