feat: add postgres telemetry recorder with two-tier degradation

2026-07-21 00:50:33 -04:00
parent 0e22fcf433
commit abb65c2324
5 changed files with 359 additions and 12 deletions
@@ -0,0 +1,159 @@
+"""PostgresRecorder 集成测试(M2 设计 §5;真实实验室 Postgres,polygateway 专用库)。
+
+DSN 走 .env `PGW_TELEMETRY_PG_DSN`,缺则 skip。该实例上有 app/chs_prod 等
+在用库——本测试只允许连 polygateway 专用库(fixture 里守卫)。
+"""
+
+from __future__ import annotations
+
+import asyncio
+import os
+
+import pytest
+from dotenv import dotenv_values
+
+from polygateway.telemetry.postgres import PostgresRecorder
+
+_EXPECTED_COLUMNS = [
+    "call_id",
+    "parent_call_id",
+    "session_id",
+    "model",
+    "provider",
+    "source_name",
+    "messages",
+    "response",
+    "thinking",
+    "prompt_tokens",
+    "completion_tokens",
+    "usage_source",
+    "latency_ms",
+    "ttft_ms",
+    "max_inter_token_ms",
+    "cache_hit",
+    "error",
+    "cost",
+    "created_at",
+]
+
+
+def _dsn() -> str | None:
+    merged = {**dotenv_values(".env"), **os.environ}
+    raw = merged.get("PGW_TELEMETRY_PG_DSN")
+    if not raw:
+        return None
+    scheme, sep, rest = raw.partition("://")
+    return f"{scheme.partition('+')[0]}{sep}{rest}"
+
+
+@pytest.fixture
+async def dsn():
+    value = _dsn()
+    if value is None:
+        pytest.skip("PGW_TELEMETRY_PG_DSN 未配置")
+    # 隔离守卫: 该实例有 app/chs_prod/mimiciv 等在用库,只许打 polygateway 专用库
+    if not value.rstrip("/").endswith("/polygateway"):
+        pytest.fail(f"遥测测试只允许连 polygateway 专用库,当前 DSN 库名不符: {value!r}")
+    import asyncpg
+
+    conn = await asyncpg.connect(value, timeout=10)
+    try:
+        await conn.execute("DROP TABLE IF EXISTS llm_calls")
+    finally:
+        await conn.close()
+    return value
+
+
+async def _record_minimal(recorder: PostgresRecorder, call_id: str = "c1", **overrides) -> None:
+    fields = {
+        "call_id": call_id,
+        "parent_call_id": None,
+        "session_id": "sess-1",
+        "model": "m",
+        "provider": "p",
+        "source_name": "s1",
+        "messages": "[]",
+        "response": "ok",
+        "thinking": "",
+        "prompt_tokens": 1,
+        "completion_tokens": 2,
+        "usage_source": "measured",
+        "latency_ms": 10,
+        "ttft_ms": None,
+        "max_inter_token_ms": None,
+        "cache_hit": False,
+        "error": None,
+        "cost": None,
+    }
+    fields.update(overrides)
+    await recorder.record_llm_call(**fields)
+
+
+async def _fetch(dsn: str, sql: str):
+    import asyncpg
+
+    conn = await asyncpg.connect(dsn, timeout=10)
+    try:
+        return await conn.fetch(sql)
+    finally:
+        await conn.close()
+
+
+class TestSchema:
+    async def test_schema_has_frozen_columns_in_order(self, dsn):
+        recorder = PostgresRecorder(dsn)
+        try:
+            await _record_minimal(recorder)
+            rows = await _fetch(
+                dsn,
+                "SELECT column_name FROM information_schema.columns "
+                "WHERE table_name='llm_calls' ORDER BY ordinal_position",
+            )
+            assert [r["column_name"] for r in rows] == _EXPECTED_COLUMNS
+        finally:
+            await recorder.aclose()
+
+    async def test_call_id_idempotent(self, dsn):
+        recorder = PostgresRecorder(dsn)
+        try:
+            await _record_minimal(recorder, call_id="dup")
+            await _record_minimal(recorder, call_id="dup", response="second")
+            rows = await _fetch(dsn, "SELECT response FROM llm_calls WHERE call_id='dup'")
+            assert [r["response"] for r in rows] == ["ok"]  # ON CONFLICT DO NOTHING
+        finally:
+            await recorder.aclose()
+
+    async def test_concurrent_writes_all_land(self, dsn):
+        recorder = PostgresRecorder(dsn)
+        try:
+            await asyncio.gather(*(_record_minimal(recorder, call_id=f"c{i}") for i in range(50)))
+            rows = await _fetch(dsn, "SELECT count(*) AS n FROM llm_calls")
+            assert rows[0]["n"] == 50
+        finally:
+            await recorder.aclose()
+
+
+class TestDegradation:
+    async def test_unreachable_server_degrades_silently(self):
+        """结构性失败(建池不通)→ warning 一次后永久降级,业务零感知。"""
+        recorder = PostgresRecorder("postgresql://u:p@127.0.0.1:1/x")
+        await _record_minimal(recorder)  # 不抛
+        await _record_minimal(recorder, call_id="c2")  # 已降级短路,同样不抛
+        await recorder.aclose()
+
+    async def test_row_failure_does_not_poison_later_rows(self, dsn):
+        """运行时单条写失败(NUL 字节文本被 PG 拒)→ 丢该行,后续行照常落库。"""
+        recorder = PostgresRecorder(dsn)
+        try:
+            await _record_minimal(recorder, call_id="bad", response="nul\x00byte")
+            await _record_minimal(recorder, call_id="good")
+            rows = await _fetch(dsn, "SELECT call_id FROM llm_calls ORDER BY call_id")
+            assert [r["call_id"] for r in rows] == ["good"]
+        finally:
+            await recorder.aclose()
+
+    async def test_aclose_idempotent(self, dsn):
+        recorder = PostgresRecorder(dsn)
+        await _record_minimal(recorder)
+        await recorder.aclose()
+        await recorder.aclose()