fix: retry stale keep-alive requests (#5893)

tests/test_request_utils.py

@@ -0,0 +1,100 @@
+import requests
+
+from app.utils.http import RequestUtils
+
+
+class _FakeSession:
+    """
+    测试用 requests.Session 替身，记录请求次数与连接池关闭行为。
+    """
+
+    def __init__(self, side_effects):
+        """
+        初始化请求结果序列。
+
+        :param side_effects: 每次 request 调用要返回或抛出的对象
+        """
+        self.side_effects = list(side_effects)
+        self.calls = []
+        self.close_count = 0
+
+    def request(self, method, url, **kwargs):
+        """
+        模拟 requests.Session.request。
+        """
+        self.calls.append((method, url, kwargs))
+        effect = self.side_effects.pop(0)
+        if isinstance(effect, Exception):
+            raise effect
+        return effect
+
+    def close(self):
+        """
+        模拟清空 session 连接池。
+        """
+        self.close_count += 1
+
+
+def _make_response(status_code: int = 200) -> requests.Response:
+    response = requests.Response()
+    response.status_code = status_code
+    return response
+
+
+def test_request_utils_retries_idempotent_session_connection_error():
+    """
+    同步幂等请求遇到失效 session 连接时应清理连接池并重试一次。
+    """
+    response = _make_response()
+    session = _FakeSession(
+        [
+            requests.exceptions.ConnectionError("stale keep-alive"),
+            response,
+        ]
+    )
+    request_utils = RequestUtils(session=session)
+
+    result = request_utils.get_res("https://example.com/data")
+
+    assert result is response
+    assert len(session.calls) == 2
+    assert session.close_count == 1
+
+
+def test_request_utils_does_not_retry_non_idempotent_connection_error():
+    """
+    非幂等请求连接异常时不应自动重试，避免重复提交副作用。
+    """
+    session = _FakeSession(
+        [
+            requests.exceptions.ConnectionError("connection failed"),
+            _make_response(),
+        ]
+    )
+    request_utils = RequestUtils(session=session)
+
+    result = request_utils.post_res("https://example.com/data", data={"name": "demo"})
+
+    assert result is None
+    assert len(session.calls) == 1
+    assert session.close_count == 0
+
+
+def test_request_utils_raises_retry_error_when_retry_still_fails():
+    """
+    开启 raise_exception 后，重试仍失败时应抛出重试阶段的异常。
+    """
+    first_error = requests.exceptions.ConnectionError("stale keep-alive")
+    retry_error = requests.exceptions.ConnectionError("proxy still unavailable")
+    session = _FakeSession([first_error, retry_error])
+    request_utils = RequestUtils(session=session)
+
+    try:
+        request_utils.get_res("https://example.com/data", raise_exception=True)
+    except requests.exceptions.ConnectionError as err:
+        assert err is retry_error
+    else:
+        raise AssertionError("请求重试失败时应抛出异常")
+
+    assert len(session.calls) == 2
+    assert session.close_count == 1