From d928ddfb779e8204270861c64b53bd22f241d1a6 Mon Sep 17 00:00:00 2001
From: Henry Su <henrysu4707@gmail.com>
Date: Sat, 19 Sep 2026 13:42:52 -0500
Subject: [PATCH] fix(realtime): include connection params in WebSocket URL

---
 src/realtime/src/realtime/_async/client.py | 10 +++++----
 src/realtime/tests/test_connection.py      | 25 ++++++++++++++++++++++
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/src/realtime/src/realtime/_async/client.py b/src/realtime/src/realtime/_async/client.py
index a9b98850..da289d62 100644
--- a/src/realtime/src/realtime/_async/client.py
+++ b/src/realtime/src/realtime/_async/client.py
@@ -5,7 +5,7 @@
 import sys
 from functools import wraps
 from typing import Any, Callable, Dict, List, Optional, Union
-from urllib.parse import urlencode, urlparse, urlunparse
+from urllib.parse import parse_qsl, urlencode, urlparse, urlunparse
 from warnings import warn
 
 import websockets
@@ -163,11 +163,12 @@ async def connect(self) -> None:
         retries = 0
         backoff = self.initial_backoff
 
-        logger.debug(f"Attempting to connect to WebSocket at {self.url}")
+        endpoint_url = self.endpoint_url()
+        logger.debug(f"Attempting to connect to WebSocket at {endpoint_url}")
 
         while retries < self.max_retries:
             try:
-                ws = await connect(self.url)
+                ws = await connect(endpoint_url)
                 self._ws_connection = ws
                 logger.debug("WebSocket connection established successfully")
                 return await self._on_connect()
@@ -393,7 +394,8 @@ async def _leave_open_topic(self, topic: str):
 
     def endpoint_url(self) -> str:
         parsed_url = urlparse(self.url)
-        query = urlencode({**self.params, "vsn": VSN}, doseq=True)
+        current_params = dict(parse_qsl(parsed_url.query, keep_blank_values=True))
+        query = urlencode({**self.params, **current_params, "vsn": VSN}, doseq=True)
         return urlunparse(
             (
                 parsed_url.scheme,
diff --git a/src/realtime/tests/test_connection.py b/src/realtime/tests/test_connection.py
index 4d1c6209..a304ca98 100644
--- a/src/realtime/tests/test_connection.py
+++ b/src/realtime/tests/test_connection.py
@@ -1,6 +1,8 @@
 import asyncio
 import datetime
 import os
+from unittest.mock import AsyncMock, patch
+from urllib.parse import parse_qs, urlparse
 
 import aiohttp
 import pytest
@@ -80,6 +82,29 @@ def test_init_client():
     assert client.timeout == DEFAULT_TIMEOUT
 
 
+@pytest.mark.asyncio
+async def test_connect_includes_connection_params() -> None:
+    client = AsyncRealtimeClient(
+        "https://project.supabase.co/realtime/v1",
+        "publishable-key",
+        params={"log_level": "info"},
+    )
+
+    with (
+        patch("realtime._async.client.connect", new_callable=AsyncMock) as connect,
+        patch.object(client, "_on_connect", new_callable=AsyncMock),
+    ):
+        await client.connect()
+
+    assert connect.await_args is not None
+    websocket_url = urlparse(connect.await_args.args[0])
+    assert parse_qs(websocket_url.query) == {
+        "apikey": ["publishable-key"],
+        "log_level": ["info"],
+        "vsn": ["1.0.0"],
+    }
+
+
 @pytest.mark.asyncio
 async def test_broadcast_events(socket: AsyncRealtimeClient):
     await socket.connect()