add polling transport option

Author: adhami3310

reflex/.templates/web/utils/state.js

@@ -854,7 +854,7 @@ export const useEventLoop = (
       await connect(
         socket,
         dispatch,
-        ["websocket"],
+        [env.TRANSPORT],
         setConnectErrors,
         client_storage,
         navigate,

reflex/app.py

@@ -531,20 +531,17 @@ def _setup_state(self) -> None:
         if not self.sio:
             self.sio = AsyncServer(
                 async_mode="asgi",
-                cors_allowed_origins=(
-                    "*"
-                    if config.cors_allowed_origins == ("*",)
-                    else list(config.cors_allowed_origins)
-                ),
-                cors_credentials=True,
+                cors_allowed_origins=[],
+                cors_credentials=False,
                 max_http_buffer_size=environment.REFLEX_SOCKET_MAX_HTTP_BUFFER_SIZE.get(),
                 ping_interval=environment.REFLEX_SOCKET_INTERVAL.get(),
                 ping_timeout=environment.REFLEX_SOCKET_TIMEOUT.get(),
                 json=SimpleNamespace(
                     dumps=staticmethod(format.json_dumps),
                     loads=staticmethod(json.loads),
                 ),
-                transports=["websocket"],
+                allow_upgrades=False,
+                transports=[config.transport],
             )
         elif getattr(self.sio, "async_mode", "") != "asgi":
             msg = f"Custom `sio` must use `async_mode='asgi'`, not '{self.sio.async_mode}'."

reflex/config.py

@@ -10,7 +10,7 @@
 from importlib.util import find_spec
 from pathlib import Path
 from types import ModuleType
-from typing import TYPE_CHECKING, Any, ClassVar
+from typing import TYPE_CHECKING, Any, ClassVar, Literal
 
 from reflex import constants
 from reflex.constants.base import LogLevel
@@ -254,6 +254,9 @@ class BaseConfig:
     # List of fully qualified import paths of plugins to disable in the app (e.g. reflex.plugins.sitemap.SitemapPlugin).
     disable_plugins: list[str] = dataclasses.field(default_factory=list)
 
+    # The transport method for client-server communication.
+    transport: Literal["websocket", "polling"] = "websocket"
+
     # Whether to skip plugin checks.
     _skip_plugins_checks: bool = dataclasses.field(default=False, repr=False)
 

reflex/utils/build.py

@@ -20,6 +20,7 @@ def set_env_json():
         str(prerequisites.get_web_dir() / constants.Dirs.ENV_JSON),
         {
             **{endpoint.name: endpoint.get_url() for endpoint in constants.Endpoint},
+            "TRANSPORT": get_config().transport,
             "TEST_MODE": is_in_app_harness(),
         },
     )