浏览器自动恢复逻辑

tests/test_browser_reconnect.py

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+"""浏览器池 driver 断链自动恢复逻辑的单元测试（不启动真实 Chromium）。
+
+覆盖本次修复的核心：
+- is_disconnect_error 对 WriteUnixTransport "the handler is closed" 等断链错误的识别
+- _run_with_reconnect 在断链后重建一次并重试成功
+- _browser_generation 守卫：并发下他人已重建时不重复重建
+"""
+from __future__ import annotations
+
+import pytest
+
+from app.core.config import Settings
+from app.services.browser_pool import BrowserPool
+
+
+class _FakeBrowser:
+    def __init__(self, connected: bool = True):
+        self._connected = connected
+
+    def is_connected(self) -> bool:
+        return self._connected
+
+
+def _make_pool(**overrides) -> BrowserPool:
+    settings = Settings(**overrides)
+    pool = BrowserPool(settings)
+    pool._browser = _FakeBrowser()
+    pool._started = True
+    pool._browser_generation = 1
+    return pool
+
+
+# 复现线上崩溃日志里的真实报错文本
+_HANDLER_CLOSED = (
+    "Stealth.hooked_new_context_async: unable to perform operation on "
+    "<WriteUnixTransport closed=True reading=False 0x7f9a27185a40>; the handler is closed"
+)
+
+
+def test_is_disconnect_error_recognizes_closed_transport():
+    assert BrowserPool.is_disconnect_error(RuntimeError(_HANDLER_CLOSED)) is True
+    assert BrowserPool.is_disconnect_error(Exception("connection closed")) is True
+    # 业务异常不应被误判为断链
+    assert BrowserPool.is_disconnect_error(ValueError("invalid selector")) is False
+
+
+@pytest.mark.asyncio
+async def test_run_with_reconnect_rebuilds_then_retries(monkeypatch):
+    """首次因断链失败 → 重建一次 → 第二次成功。"""
+    pool = _make_pool()
+    rebuilt: list[str] = []
+
+    async def fake_restart(reason, *, observed_generation=None):
+        rebuilt.append(reason)
+        pool._browser_generation += 1  # 模拟 start() 自增代次
+
+    monkeypatch.setattr(pool, "_restart_browser", fake_restart)
+
+    attempts = {"n": 0}
+
+    async def factory():
+        attempts["n"] += 1
+        if attempts["n"] == 1:
+            raise RuntimeError(_HANDLER_CLOSED)
+        return "ok"
+
+    result = await pool._run_with_reconnect(factory, "测试操作")
+
+    assert result == "ok"
+    assert attempts["n"] == 2
+    assert len(rebuilt) == 1
+
+
+@pytest.mark.asyncio
+async def test_run_with_reconnect_gives_up_after_one_retry(monkeypatch):
+    """连续两次断链：只重试一次，第二次仍失败则抛出。"""
+    pool = _make_pool()
+
+    async def fake_restart(reason, *, observed_generation=None):
+        pool._browser_generation += 1
+
+    monkeypatch.setattr(pool, "_restart_browser", fake_restart)
+
+    attempts = {"n": 0}
+
+    async def factory():
+        attempts["n"] += 1
+        raise RuntimeError(_HANDLER_CLOSED)
+
+    with pytest.raises(RuntimeError):
+        await pool._run_with_reconnect(factory, "测试操作")
+
+    assert attempts["n"] == 2  # 初次 + 一次重试
+
+
+@pytest.mark.asyncio
+async def test_run_with_reconnect_passes_through_non_disconnect(monkeypatch):
+    """非断链异常不触发重建，直接抛出。"""
+    pool = _make_pool()
+    rebuilt: list[str] = []
+
+    async def fake_restart(reason, *, observed_generation=None):
+        rebuilt.append(reason)
+
+    monkeypatch.setattr(pool, "_restart_browser", fake_restart)
+
+    async def factory():
+        raise ValueError("业务错误")
+
+    with pytest.raises(ValueError):
+        await pool._run_with_reconnect(factory, "测试操作")
+
+    assert rebuilt == []
+
+
+@pytest.mark.asyncio
+async def test_restart_browser_skips_when_generation_changed():
+    """持锁后代次已变化（他人已重建）→ 直接返回，不重复重建。"""
+    pool = _make_pool()
+
+    closed: list[str] = []
+
+    async def fake_close():
+        closed.append("close")
+
+    pool.close = fake_close  # type: ignore[method-assign]
+
+    # 调用方观察到的是旧代次，而当前代次已被他人推进
+    await pool._restart_browser("stale", observed_generation=pool._browser_generation - 1)
+
+    assert closed == []  # 未触发关闭/重建
+
+
+@pytest.mark.asyncio
+async def test_open_context_and_page_closes_context_on_page_failure(monkeypatch):
+    """页面创建失败时关闭半开上下文，避免泄漏。"""
+    pool = _make_pool()
+
+    class _Ctx:
+        def __init__(self):
+            self.closed = False
+
+        async def new_page(self):
+            raise RuntimeError("new_page boom")
+
+    ctx = _Ctx()
+
+    async def fake_new_context_raw(storage_state):
+        return ctx
+
+    closed: list[object] = []
+
+    async def fake_close_context(c):
+        closed.append(c)
+
+    monkeypatch.setattr(pool, "_new_context_raw", fake_new_context_raw)
+    monkeypatch.setattr(pool, "close_context", fake_close_context)
+
+    with pytest.raises(RuntimeError, match="new_page boom"):
+        await pool._open_context_and_page(None)
+
+    assert closed == [ctx]