refactor(runtime): tighten resource cleanup and test isolation (#6116)

tests/test_doh_helper.py

@@ -3,6 +3,61 @@ import socket
 from app.helper import doh
 
 
+def test_doh_executor_is_lazy_and_shutdown_restores_socket(monkeypatch):
+    """DoH 线程池按需创建，并在模块关闭时恢复系统 DNS"""
+    original_getaddrinfo = socket.getaddrinfo
+    helper = object.__new__(doh.DohHelper)
+    monkeypatch.setattr(doh.settings, "DOH_DOMAINS", "example.com")
+    monkeypatch.setattr(doh.settings, "DOH_RESOLVERS", "resolver.test")
+    monkeypatch.setattr(doh, "_doh_query", lambda resolver, host: "203.0.113.7")
+    monkeypatch.setattr(doh, "_orig_getaddrinfo", lambda host, *args, **kwargs: [])
+
+    try:
+        helper.shutdown()
+        assert doh._executor is None
+
+        doh.enable_doh(True)
+        socket.getaddrinfo("example.com", None)
+        executor = doh._executor
+        assert executor is not None
+
+        helper.shutdown()
+
+        assert doh._executor is None
+        assert socket.getaddrinfo is doh._orig_getaddrinfo
+        assert getattr(executor, "_shutdown", False)
+    finally:
+        helper.shutdown()
+        socket.getaddrinfo = original_getaddrinfo
+
+
+def test_doh_config_reload_disables_and_closes_executor(monkeypatch):
+    """热更新关闭 DoH 时恢复系统 DNS 并释放已创建的线程池"""
+    original_getaddrinfo = socket.getaddrinfo
+    helper = object.__new__(doh.DohHelper)
+    monkeypatch.setattr(doh.settings, "DOH_DOMAINS", "example.com")
+    monkeypatch.setattr(doh.settings, "DOH_RESOLVERS", "resolver.test")
+    monkeypatch.setattr(doh, "_doh_query", lambda resolver, host: "203.0.113.7")
+    monkeypatch.setattr(doh, "_orig_getaddrinfo", lambda host, *args, **kwargs: [])
+
+    try:
+        helper.shutdown()
+        doh.enable_doh(True)
+        socket.getaddrinfo("example.com", None)
+        executor = doh._executor
+        assert executor is not None
+        monkeypatch.setattr(doh.settings, "DOH_ENABLE", False)
+
+        helper.on_config_changed()
+
+        assert doh._executor is None
+        assert getattr(executor, "_shutdown", False)
+        assert socket.getaddrinfo is doh._orig_getaddrinfo
+    finally:
+        helper.shutdown()
+        socket.getaddrinfo = original_getaddrinfo
+
+
 def test_enable_doh_reuses_cached_host_resolution(monkeypatch):
     """
     同一 DoH 域名第二次解析应命中缓存，避免重复请求远端解析器。
@@ -33,6 +88,7 @@ def test_enable_doh_reuses_cached_host_resolution(monkeypatch):
         socket.getaddrinfo("example.com", None)
         socket.getaddrinfo("example.com", None)
     finally:
+        object.__new__(doh.DohHelper).shutdown()
         socket.getaddrinfo = original_getaddrinfo
         with doh._doh_lock:
             doh._doh_cache.clear()