added bounded close session for curl_cffi/past_prices to pricing model

tests/test_session_close_budget.py

@@ -0,0 +1,135 @@
+"""unit test: a session's close cannot park the caller indefinitely
+
+run from the repo root:
+    uv run pytest tests/test_session_close_budget.py
+
+offline — no network. curl_cffi's close awaits the multi handle with no timeout
+of its own, so a wedged transfer would park whatever closes the session,
+including an `async with` exit. These build a real session and wedge the
+backend's close, asserting the bound lives on the session itself so every call
+site gets it without arranging anything.
+"""
+
+import asyncio
+import logging
+
+from aioproxies import AioProxies
+
+from monitor_utils import sessions
+from monitor_utils.sessions import BoundedCloseSession, get_default_session
+
+
+def _proxies(tmp_path) -> AioProxies:
+    """A one-entry pool in the host:port:user:pass format monitors ship."""
+    proxy_file = tmp_path / "proxies.txt"
+    proxy_file.write_text("proxy.example.io:8080:user:secret\n")
+    return AioProxies.from_file(path=str(proxy_file))
+
+
+async def _wedge_close(session) -> asyncio.Event:
+    """Replace the backend's close with one that never returns.
+
+    Builds the backend session first so TLSSession.close actually reaches the
+    backend rather than short-circuiting on an unbuilt session.
+    """
+
+    session.session  # force lazy construction
+    started = asyncio.Event()
+
+    async def wedged(inner_session):
+        started.set()
+        await asyncio.sleep(3600)
+
+    session.backend.close = wedged
+    return started
+
+
+async def _really_close(session, original_close):
+    """Close for real, so the test does not leak the curl handle it allocated."""
+    session.backend.close = original_close
+    await session.close()
+
+
+def test_close_is_abandoned_when_it_exceeds_the_budget(monkeypatch, caplog, tmp_path):
+    """A close that never returns is abandoned and logged, not awaited forever."""
+
+    monkeypatch.setattr(sessions, "SESSION_CLOSE_TIMEOUT_SECONDS", 0.05)
+    proxies = _proxies(tmp_path)
+
+    async def run():
+        session = get_default_session(proxies, timeout=8)
+        original_close = session.backend.close
+        started = await _wedge_close(session)
+
+        # wait_for is the assertion: an unbounded close never returns here
+        await asyncio.wait_for(session.close(), timeout=5)
+
+        assert started.is_set()
+        await _really_close(session, original_close)
+
+    with caplog.at_level(logging.ERROR, logger="monitor_utils.sessions"):
+        asyncio.run(run())
+
+    assert any(
+        record.message == "session close exceeded budget, abandoning session"
+        for record in caplog.records
+    )
+
+
+def test_async_with_exit_is_bounded(monkeypatch, caplog, tmp_path):
+    """The bound applies through `async with`, which is how monitors close."""
+
+    monkeypatch.setattr(sessions, "SESSION_CLOSE_TIMEOUT_SECONDS", 0.05)
+    proxies = _proxies(tmp_path)
+
+    async def run():
+        session = get_default_session(proxies, timeout=8)
+        original_close = session.backend.close
+        started = await _wedge_close(session)
+
+        async with session:
+            pass
+
+        assert started.is_set()
+        await _really_close(session, original_close)
+
+    with caplog.at_level(logging.ERROR, logger="monitor_utils.sessions"):
+        asyncio.run(asyncio.wait_for(run(), timeout=5))
+
+    assert any(
+        record.message == "session close exceeded budget, abandoning session"
+        for record in caplog.records
+    )
+
+
+def test_healthy_close_completes_and_is_not_logged(caplog, tmp_path):
+    """The normal path closes fully and reports nothing."""
+
+    proxies = _proxies(tmp_path)
+
+    async def run():
+        session = get_default_session(proxies, timeout=8)
+        session.session  # force lazy construction so close has work to do
+        await session.close()
+        return session
+
+    with caplog.at_level(logging.ERROR, logger="monitor_utils.sessions"):
+        session = asyncio.run(run())
+
+    assert session._is_closed()
+    assert not caplog.records
+
+
+def test_get_default_session_returns_a_bounded_session(tmp_path):
+    """The factory hands out the bounded type, not a bare TLSSession."""
+
+    proxies = _proxies(tmp_path)
+
+    async def run():
+        session = get_default_session(proxies, timeout=8)
+        try:
+            return isinstance(session, BoundedCloseSession)
+        finally:
+            await session.close()
+
+    assert asyncio.run(run())