fix(wechat): validate timing configuration (#4280)

README.md

@@ -427,7 +427,10 @@ channels:
     ilink_bot_id: $WECHAT_ILINK_BOT_ID
     qrcode_login_enabled: true      # optional: allow first-time QR bootstrap when bot_token is absent
     allowed_users: []               # empty = allow all
-    polling_timeout: 35
+    polling_timeout: 35             # timing values must be positive finite seconds
+    polling_retry_delay: 5
+    qrcode_poll_interval: 2
+    qrcode_poll_timeout: 180
     state_dir: ./.deer-flow/wechat/state
     max_inbound_image_bytes: 20971520
     max_outbound_image_bytes: 20971520

backend/AGENTS.md

@@ -546,6 +546,7 @@ The cached value is reused for both the blocking (`runs.wait`) and streaming (`_
 - Disabled by default. It is a user-binding layer on top of the existing `channels.*` runtime config, not a replacement for provider bot credentials.
 - No public IP, OAuth callback URL, or provider webhook route is required by the current implementation.
 - Telegram uses a deep-link `/start <code>` flow over the existing long-polling worker. Slack, Discord, Feishu/Lark, DingTalk, WeChat, and WeCom use `/connect <code>` over their existing outbound channel workers.
+- WeChat timing settings (`polling_timeout`, `polling_retry_delay`, `qrcode_poll_interval`, `qrcode_poll_timeout`) accept only positive finite seconds; invalid values fall back to their defaults so polling cannot enter a hot loop or sleep forever.
 - Frontend APIs: `GET /api/channels/providers`, `GET /api/channels/connections`, `POST /api/channels/{provider}/connect`, and `DELETE /api/channels/connections/{connection_id}`.
 - Browser APIs remain protected by normal Gateway auth/CSRF. Provider messages arrive through the already-configured channel workers.
 - Provider-level `connection_status` reflects the user's newest connection row. With no binding it is `not_connected`, except in auth-disabled local mode where a configured running channel reports `connected` because all channel messages already route to the default user.

backend/app/channels/wechat.py

@@ -8,6 +8,7 @@ import binascii
 import hashlib
 import json
 import logging
+import math
 import mimetypes
 import secrets
 import tempfile
@@ -1456,9 +1457,10 @@ class WechatChannel(Channel):
     @staticmethod
     def _coerce_float(value: Any, default: float) -> float:
         try:
-            return float(value)
-        except (TypeError, ValueError):
+            parsed = float(value)
+        except (OverflowError, TypeError, ValueError):
             return default
+        return parsed if math.isfinite(parsed) and parsed > 0 else default
 
     @staticmethod
     def _coerce_int(value: Any, default: int) -> int:

backend/tests/test_wechat_channel.py

@@ -84,6 +84,33 @@ class _MockAsyncClient:
         return None
 
 
+def test_timing_config_requires_positive_finite_values():
+    from app.channels.wechat import WechatChannel
+
+    timing_defaults = {
+        "polling_timeout": WechatChannel.DEFAULT_POLLING_TIMEOUT,
+        "polling_retry_delay": WechatChannel.DEFAULT_RETRY_DELAY,
+        "qrcode_poll_interval": WechatChannel.DEFAULT_QRCODE_POLL_INTERVAL,
+        "qrcode_poll_timeout": WechatChannel.DEFAULT_QRCODE_POLL_TIMEOUT,
+    }
+    attributes = {
+        "polling_timeout": "_polling_timeout",
+        "polling_retry_delay": "_retry_delay",
+        "qrcode_poll_interval": "_qrcode_poll_interval",
+        "qrcode_poll_timeout": "_qrcode_poll_timeout",
+    }
+
+    for invalid in (0, -1, float("nan"), float("inf"), float("-inf"), 10**1000):
+        channel = WechatChannel(
+            bus=MessageBus(),
+            config={"bot_token": "test-token", **dict.fromkeys(timing_defaults, invalid)},
+        )
+        assert {key: getattr(channel, attributes[key]) for key in timing_defaults} == timing_defaults
+
+    channel = WechatChannel(bus=MessageBus(), config={"bot_token": "test-token", "polling_retry_delay": "0.25"})
+    assert channel._retry_delay == 0.25
+
+
 def test_handle_update_publishes_private_chat_message():
     from app.channels.wechat import WechatChannel
 

config.example.yaml

@@ -1856,11 +1856,12 @@ run_ownership:
 #     # Optional: sent as SKRouteTag header when provided
 #     route_tag: ""
 #     allowed_users: []               # empty = allow all
-#     # Optional: long-polling timeout in seconds
+#     # Optional: timing values must be positive finite seconds
 #     polling_timeout: 35
-#     # Optional: QR poll interval in seconds when qrcode_login_enabled is true
+#     polling_retry_delay: 5
+#     # QR poll interval when qrcode_login_enabled is true
 #     qrcode_poll_interval: 2
-#     # Optional: QR bootstrap timeout in seconds
+#     # QR bootstrap timeout
 #     qrcode_poll_timeout: 180
 #     # Optional: persist getupdates cursor under the gateway container volume
 #     state_dir: ./.deer-flow/wechat/state