xtekky/gpt4free · error · RuntimeError

curl_cffi WebSocket is not available on this platform

Error message

curl_cffi WebSocket is not available on this platform

What it means

Constructor of the stub WebSocket class in g4f/requests/curl_cffi.py, defined for the case where curl_cffi is missing or lacks WebSocket support (has_curl_ws false). Instantiation raises RuntimeError('curl_cffi WebSocket is not available on this platform'). curl_cffi's WebSocket API is relatively new, so a present-but-old curl_cffi still lands in this branch.

Source

Thrown at g4f/requests/curl_cffi.py:204

        async def receive_str(self, **kwargs) -> str:
            method = (
                self.inner.arecv if hasattr(self.inner, "arecv") else self.inner.recv
            )
            bytes, _ = await method()
            return bytes.decode(errors="ignore")

        async def send_str(self, data: str):
            method = (
                self.inner.asend if hasattr(self.inner, "asend") else self.inner.send
            )
            await method(data.encode(), CurlWsFlag.TEXT)

else:

    class WebSocket:
        def __init__(self, *args, **kwargs) -> None:
            raise RuntimeError("curl_cffi WebSocket is not available on this platform")

View on GitHub (pinned to 973504e177)

Solutions

pip install -U curl_cffi so both the WebSocket API and CurlWsFlag exist.
Verify the import chain: python -c "from curl_cffi import CurlWsFlag" — failure confirms the version is too old.
If upgrading is impossible, use aiohttp's ws_connect for plain WebSocket needs (losing TLS impersonation).

Defensive patterns

Strategy: validation

Validate before calling

from g4f.requests.curl_cffi import has_curl_cffi, has_curl_ws

ws_ok = has_curl_cffi and has_curl_ws

Try / catch

try:
    ws = WebSocket(session, url)
except RuntimeError as e:
    if "WebSocket" in str(e):
        ws = await session.ws_connect(url)  # aiohttp websocket fallback
    else:
        raise

Prevention

Verify `from curl_cffi import CurlWsFlag` after upgrades; WebSocket support requires a recent version.
Detect has_curl_ws before opening impersonated websockets.
Keep an aiohttp ws_connect fallback path for environments without modern curl_cffi.

When it happens

Trigger: Constructing WebSocket(session, url) from this module when curl_cffi is absent, or when the installed version predates the CurlWsFlag/websocket API used by the real wrapper. The failure happens at construction, before any connection attempt.

Common situations: Old curl_cffi pinned in requirements (websocket support arrived in newer releases); providers that tunnel through websockets with browser TLS fingerprints on such environments; partially upgraded environments.

Related errors

AI-assisted analysis of xtekky/gpt4free@973504e177 (2026-08-14). Data as JSON: /api/errors/c349660a41eb2d7b. Report an issue: GitHub.