Expose app.add_all_routes_endpoint for flexgen

reflex/app.py

@@ -614,6 +614,8 @@ class App(MiddlewareMixin, LifespanMixin):
             self.api.get(str(constants.Endpoint.AUTH_CODESPACE))(
                 codespaces.auth_codespace
             )
+        if environment.REFLEX_ADD_ALL_ROUTES_ENDPOINT.get():
+            self.add_all_routes_endpoint()
 
     def _add_cors(self):
         """Add CORS middleware to the app."""
@@ -1360,7 +1362,7 @@ class App(MiddlewareMixin, LifespanMixin):
             for output_path, code in compile_results:
                 compiler_utils.write_page(output_path, code)
 
-        # Pickle dynamic states
+        # Write list of routes that create dynamic states for backend to use.
         if self._state is not None:
             stateful_pages_marker = (
                 prerequisites.get_backend_dir() / constants.Dirs.STATEFUL_PAGES
@@ -1369,6 +1371,15 @@ class App(MiddlewareMixin, LifespanMixin):
             with stateful_pages_marker.open("w") as f:
                 json.dump(list(self._stateful_pages), f)
 
+    def add_all_routes_endpoint(self):
+        """Add an endpoint to the app that returns all the routes."""
+        if not self.api:
+            return
+
+        @self.api.get(str(constants.Endpoint.ALL_ROUTES))
+        async def all_routes():
+            return list(self._unevaluated_pages.keys())
+
     @contextlib.asynccontextmanager
     async def modify_state(self, token: str) -> AsyncIterator[BaseState]:
         """Modify the state out of band.

reflex/config.py

@@ -712,6 +712,9 @@ class EnvironmentVariables:
     # Paths to exclude from the hot reload. Takes precedence over include paths. Separated by a colon.
     REFLEX_HOT_RELOAD_EXCLUDE_PATHS: EnvVar[List[Path]] = env_var([])
 
+    # Used by flexgen to enumerate the pages.
+    REFLEX_ADD_ALL_ROUTES_ENDPOINT: EnvVar[bool] = env_var(False)
+
 
 environment = EnvironmentVariables()
 

reflex/constants/event.py

@@ -12,6 +12,7 @@ class Endpoint(Enum):
     UPLOAD = "_upload"
     AUTH_CODESPACE = "auth-codespace"
     HEALTH = "_health"
+    ALL_ROUTES = "_all_routes"
 
     def __str__(self) -> str:
         """Get the string representation of the endpoint.