feat: add sqlite telemetry with single-emitter discipline

src/polygateway/middleware/telemetry.py

@@ -0,0 +1,182 @@
+"""TelemetryMW + TelemetryEmitter: 遥测调用点收敛为单一 helper(铁律)。
+
+Emitter 是全库**唯一**调用 `record_llm_call` 的地方(三项目 4 处逐字复制
+15 参调用的教训)。分工: RetryMW 经 Emitter 逐次记录每次尝试;TelemetryMW
+(最外层)只记尝试层看不见的事件——缓存命中、scope 级失败、取消;
+RequestRejected/ResultInvalid 已被尝试层记录,最外层放行不重复记。
+"""
+
+from __future__ import annotations
+
+import asyncio
+import json
+import time
+import uuid
+from typing import TYPE_CHECKING
+
+from loguru import logger
+
+from polygateway.errors import GatewayUnavailableError, GovernanceBackendError
+from polygateway.middleware.cache import digest_messages
+
+if TYPE_CHECKING:
+    from collections.abc import Callable
+
+    from polygateway.ports import CallNext, TelemetryRecorder
+    from polygateway.types import ChatRequest, LLMResponse, SourceConfig
+
+
+class TelemetryEmitter:
+    """从请求与结果组装 18 字段并写入 recorder;一切写失败降级 warning。"""
+
+    def __init__(self, recorder: TelemetryRecorder) -> None:
+        self._recorder = recorder
+
+    async def emit_attempt(
+        self,
+        *,
+        request: ChatRequest,
+        source: SourceConfig,
+        call_id: str,
+        latency_ms: int,
+        response: LLMResponse | None,
+        error: str | None,
+    ) -> None:
+        """逐次尝试记录(RetryMW 调用);失败尝试 usage 按 estimated 记 0。"""
+        await self._record(
+            request=request,
+            call_id=call_id,
+            model=source.model,
+            provider=source.provider,
+            source_name=source.name,
+            response_text=response.content if response else "",
+            thinking=response.thinking if response else "",
+            prompt_tokens=response.prompt_tokens if response else 0,
+            completion_tokens=response.completion_tokens if response else 0,
+            usage_source=response.usage_source if response else "estimated",
+            latency_ms=latency_ms,
+            ttft_ms=response.ttft_ms if response else None,
+            max_inter_token_ms=response.max_inter_token_ms if response else None,
+            cache_hit=False,
+            error=error,
+        )
+
+    async def emit_cache_hit(self, *, request: ChatRequest, response: LLMResponse) -> None:
+        """缓存命中记录: cache_hit=True、latency_ms=0(VT 同款)。"""
+        await self._record(
+            request=request,
+            call_id=response.call_id,
+            model=response.model,
+            provider=response.provider,
+            source_name=response.source_name,
+            response_text=response.content,
+            thinking=response.thinking,
+            prompt_tokens=response.prompt_tokens,
+            completion_tokens=response.completion_tokens,
+            usage_source=response.usage_source,
+            latency_ms=0,
+            ttft_ms=None,
+            max_inter_token_ms=None,
+            cache_hit=True,
+            error=None,
+        )
+
+    async def emit_terminal_failure(
+        self, *, request: ChatRequest, call_id: str, latency_ms: int, error: str
+    ) -> None:
+        """scope 级失败/取消记录: 无具体源,溯源字段置空标记。"""
+        await self._record(
+            request=request,
+            call_id=call_id,
+            model="",
+            provider="",
+            source_name="",
+            response_text="",
+            thinking="",
+            prompt_tokens=0,
+            completion_tokens=0,
+            usage_source="estimated",
+            latency_ms=latency_ms,
+            ttft_ms=None,
+            max_inter_token_ms=None,
+            cache_hit=False,
+            error=error,
+        )
+
+    async def _record(
+        self,
+        *,
+        request: ChatRequest,
+        call_id: str,
+        model: str,
+        provider: str,
+        source_name: str,
+        response_text: str,
+        thinking: str,
+        prompt_tokens: int,
+        completion_tokens: int,
+        usage_source: str,
+        latency_ms: int,
+        ttft_ms: float | None,
+        max_inter_token_ms: float | None,
+        cache_hit: bool,
+        error: str | None,
+    ) -> None:
+        try:
+            # messages 落库前多模态摘要,与缓存 key 共用同一函数(VT R12)
+            messages_json = json.dumps(digest_messages(request.messages), ensure_ascii=False)
+            await self._recorder.record_llm_call(
+                call_id=call_id,
+                parent_call_id=request.parent_call_id,
+                session_id=request.session_id,
+                model=model,
+                provider=provider,
+                source_name=source_name,
+                messages=messages_json,
+                response=response_text,
+                thinking=thinking,
+                prompt_tokens=prompt_tokens,
+                completion_tokens=completion_tokens,
+                usage_source=usage_source,
+                latency_ms=latency_ms,
+                ttft_ms=ttft_ms,
+                max_inter_token_ms=max_inter_token_ms,
+                cache_hit=cache_hit,
+                error=error,
+                cost=None,  # M1 无 pricing;M2 换算后填充
+            )
+        except asyncio.CancelledError:
+            raise
+        except Exception as exc:
+            logger.warning("遥测记录失败(降级不冒泡): {}", exc)
+
+
+class TelemetryMW:
+    """洋葱最外层: 观测尝试层看不见的路径,任何路径都留痕(遥测必录)。"""
+
+    def __init__(
+        self, emitter: TelemetryEmitter, now: Callable[[], float] = time.monotonic
+    ) -> None:
+        self._emitter = emitter
+        self._now = now
+
+    async def __call__(self, request: ChatRequest, call_next: CallNext) -> LLMResponse:
+        started = self._now()
+        try:
+            response = await call_next(request)
+        except (GatewayUnavailableError, GovernanceBackendError) as exc:
+            await self._emitter.emit_terminal_failure(
+                request=request, call_id=str(uuid.uuid4()),
+                latency_ms=int((self._now() - started) * 1000), error=str(exc),
+            )
+            raise
+        except asyncio.CancelledError:
+            # 尽力而为: 取消也留痕(§5.1 约定④);随后立即重抛
+            await self._emitter.emit_terminal_failure(
+                request=request, call_id=str(uuid.uuid4()),
+                latency_ms=int((self._now() - started) * 1000), error="cancelled",
+            )
+            raise
+        if response.cache_hit:
+            await self._emitter.emit_cache_hit(request=request, response=response)
+        return response

src/polygateway/telemetry/sqlite.py

@@ -0,0 +1,93 @@
+"""SQLite 遥测后端(默认): WAL + 单持久连接 + to_thread 桥接。
+
+蓝本 VT `adapters/telemetry.py`: 构造期建连接与表,失败降级为 no-op
+(记录基础设施不得拖垮业务调用);`INSERT OR IGNORE` 幂等(call_id 主键);
+写入经 threading.Lock 串行化后由 `asyncio.to_thread` 执行,不阻塞事件循环。
+"""
+
+from __future__ import annotations
+
+import asyncio
+import sqlite3
+import threading
+from pathlib import Path
+
+from loguru import logger
+
+_DDL = """
+CREATE TABLE IF NOT EXISTS llm_calls (
+    call_id            TEXT PRIMARY KEY,
+    parent_call_id     TEXT,
+    session_id         TEXT,
+    model              TEXT    NOT NULL,
+    provider           TEXT    NOT NULL,
+    source_name        TEXT    NOT NULL,
+    messages           TEXT    NOT NULL,
+    response           TEXT    NOT NULL,
+    thinking           TEXT    NOT NULL DEFAULT '',
+    prompt_tokens      INTEGER NOT NULL,
+    completion_tokens  INTEGER NOT NULL,
+    usage_source       TEXT    NOT NULL,
+    latency_ms         INTEGER NOT NULL,
+    ttft_ms            REAL,
+    max_inter_token_ms REAL,
+    cache_hit          INTEGER NOT NULL DEFAULT 0,
+    error              TEXT,
+    cost               REAL,
+    created_at         TEXT    NOT NULL DEFAULT (datetime('now'))
+);
+"""
+
+_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",
+)
+
+_INSERT = (
+    f"INSERT OR IGNORE INTO llm_calls ({', '.join(_COLUMNS)}) "
+    f"VALUES ({', '.join('?' for _ in _COLUMNS)})"
+)
+
+
+class SQLiteRecorder:
+    """TelemetryRecorder 端口的 SQLite 实现;初始化/写入失败全降级 warning。"""
+
+    def __init__(self, db_path: Path | str) -> None:
+        self._lock = threading.Lock()
+        self._conn: sqlite3.Connection | None = None
+        try:
+            path = Path(db_path)
+            path.parent.mkdir(parents=True, exist_ok=True)
+            conn = sqlite3.connect(path, check_same_thread=False, timeout=10.0)
+            conn.execute("PRAGMA journal_mode=WAL")
+            conn.execute("PRAGMA busy_timeout=5000")
+            conn.execute(_DDL)
+            conn.commit()
+            self._conn = conn
+        except (OSError, sqlite3.Error) as exc:
+            logger.warning("SQLite 遥测初始化失败,后续记录降级为 no-op: {}", exc)
+
+    async def record_llm_call(self, **fields: object) -> None:
+        """写一行遥测;字段集合即 18 字段冻结签名(ports.TelemetryRecorder)。"""
+        if self._conn is None:
+            return
+        row = tuple(fields[col] for col in _COLUMNS)
+        try:
+            await asyncio.to_thread(self._write, row)
+        except (OSError, sqlite3.Error) as exc:
+            logger.warning("SQLite 遥测写入失败(降级不冒泡): {}", exc)
+
+    def _write(self, row: tuple) -> None:
+        assert self._conn is not None  # 内部不变量: 调用方已判空
+        with self._lock:
+            self._conn.execute(_INSERT, row)
+            self._conn.commit()
+
+    def close(self) -> None:
+        """幂等关闭持久连接。"""
+        conn, self._conn = self._conn, None
+        if conn is not None:
+            with self._lock:
+                conn.close()

tests/unit/test_telemetry.py

@@ -0,0 +1,203 @@
+"""遥测子系统测试: SQLiteRecorder(18 列)+ TelemetryEmitter 单一 helper + TelemetryMW。"""
+
+import asyncio
+import sqlite3
+import subprocess
+from pathlib import Path
+
+import pytest
+
+from polygateway.errors import CircuitOpenError, RequestRejectedError
+from polygateway.middleware.telemetry import TelemetryEmitter, TelemetryMW
+from polygateway.telemetry.sqlite import SQLiteRecorder
+from polygateway.types import ChatRequest, LLMResponse, SourceConfig
+
+_REQ = ChatRequest(messages=[{"role": "user", "content": "hi"}], session_id="sess-1")
+
+_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 _resp(**overrides):
+    base = dict(
+        content="ok", thinking="", model="m", provider="p", prompt_tokens=1,
+        completion_tokens=2, latency_ms=30, ttft_ms=None, max_inter_token_ms=None,
+        cache_hit=False, call_id="cid-1", source_name="s1", usage_source="measured",
+    )
+    base.update(overrides)
+    return LLMResponse(**base)
+
+
+def _source():
+    return SourceConfig(
+        name="s1", provider="p", base_url="https://gw.example/v1",
+        api_key="sk", model="m", timeout_s=10.0,
+    )
+
+
+async def _record_minimal(recorder, call_id="c1", **overrides):
+    fields = dict(
+        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)
+
+
+class TestSQLiteRecorder:
+    async def test_schema_has_frozen_columns(self, tmp_path):
+        recorder = SQLiteRecorder(tmp_path / "t.db")
+        await _record_minimal(recorder)
+        recorder.close()
+        cols = [r[1] for r in sqlite3.connect(tmp_path / "t.db").execute(
+            "PRAGMA table_info(llm_calls)"
+        )]
+        assert cols == _EXPECTED_COLUMNS
+
+    async def test_call_id_idempotent(self, tmp_path):
+        recorder = SQLiteRecorder(tmp_path / "t.db")
+        await _record_minimal(recorder, call_id="dup")
+        await _record_minimal(recorder, call_id="dup", response="second")
+        recorder.close()
+        rows = sqlite3.connect(tmp_path / "t.db").execute(
+            "SELECT response FROM llm_calls WHERE call_id='dup'"
+        ).fetchall()
+        assert rows == [("ok",)]  # INSERT OR IGNORE: 第二次静默忽略
+
+    async def test_concurrent_writes_all_land(self, tmp_path):
+        recorder = SQLiteRecorder(tmp_path / "t.db")
+        await asyncio.gather(*(_record_minimal(recorder, call_id=f"c{i}") for i in range(50)))
+        recorder.close()
+        (count,) = sqlite3.connect(tmp_path / "t.db").execute(
+            "SELECT COUNT(*) FROM llm_calls"
+        ).fetchone()
+        assert count == 50
+
+    async def test_unwritable_path_degrades_silently(self):
+        recorder = SQLiteRecorder(Path("/nonexistent-root/deep/t.db"))
+        await _record_minimal(recorder)  # 不抛
+        recorder.close()
+
+
+class _MemoryRecorder:
+    def __init__(self):
+        self.rows = []
+
+    async def record_llm_call(self, **fields):
+        self.rows.append(fields)
+
+
+class TestEmitter:
+    async def test_attempt_success_row(self):
+        rec = _MemoryRecorder()
+        emitter = TelemetryEmitter(rec)
+        await emitter.emit_attempt(
+            request=_REQ, source=_source(), call_id="cid-1", latency_ms=42,
+            response=_resp(), error=None,
+        )
+        row = rec.rows[0]
+        assert row["call_id"] == "cid-1" and row["error"] is None
+        assert row["session_id"] == "sess-1" and row["source_name"] == "s1"
+        assert row["response"] == "ok" and row["cost"] is None
+
+    async def test_attempt_failure_row(self):
+        rec = _MemoryRecorder()
+        emitter = TelemetryEmitter(rec)
+        await emitter.emit_attempt(
+            request=_REQ, source=_source(), call_id="cid-2", latency_ms=7,
+            response=None, error="TransientError: boom",
+        )
+        row = rec.rows[0]
+        assert row["error"].startswith("TransientError")
+        assert row["response"] == "" and row["usage_source"] == "estimated"
+
+    async def test_multimodal_messages_digested_before_storage(self):
+        rec = _MemoryRecorder()
+        emitter = TelemetryEmitter(rec)
+        big = "data:image/png;base64," + "A" * 100_000
+        req = ChatRequest(messages=[{"role": "user", "content": [
+            {"type": "image_url", "image_url": {"url": big}},
+        ]}])
+        await emitter.emit_attempt(
+            request=req, source=_source(), call_id="c", latency_ms=1,
+            response=None, error="x",
+        )
+        assert len(rec.rows[0]["messages"]) < 500  # base64 不整段进库(VT R12)
+
+    async def test_recorder_failure_swallowed(self):
+        class Broken:
+            async def record_llm_call(self, **fields):
+                raise OSError("disk full")
+
+        emitter = TelemetryEmitter(Broken())
+        await emitter.emit_attempt(
+            request=_REQ, source=_source(), call_id="c", latency_ms=1,
+            response=_resp(), error=None,
+        )  # 不抛(降级不冒泡)
+
+
+class TestTelemetryMW:
+    async def test_cache_hit_recorded(self):
+        rec = _MemoryRecorder()
+        mw = TelemetryMW(TelemetryEmitter(rec))
+
+        async def terminal(request):
+            return _resp(cache_hit=True, latency_ms=0, call_id="cache-cid")
+
+        resp = await mw(_REQ, terminal)
+        assert resp.cache_hit
+        assert len(rec.rows) == 1
+        assert rec.rows[0]["cache_hit"] is True and rec.rows[0]["latency_ms"] == 0
+
+    async def test_normal_success_not_double_recorded(self):
+        """成功尝试由 RetryMW 逐次记录;最外层不得重复记。"""
+        rec = _MemoryRecorder()
+        mw = TelemetryMW(TelemetryEmitter(rec))
+
+        async def terminal(request):
+            return _resp(cache_hit=False)
+
+        await mw(_REQ, terminal)
+        assert rec.rows == []
+
+    async def test_scope_level_failure_recorded(self):
+        rec = _MemoryRecorder()
+        mw = TelemetryMW(TelemetryEmitter(rec))
+
+        async def terminal(request):
+            raise CircuitOpenError(scope="llm", retry_after_s=30.0)
+
+        with pytest.raises(CircuitOpenError):
+            await mw(_REQ, terminal)
+        assert len(rec.rows) == 1 and "circuit_open" in rec.rows[0]["error"]
+
+    async def test_attempt_level_failure_not_double_recorded(self):
+        """RequestRejected 已被 RetryMW 逐次记录 → 最外层跳过。"""
+        rec = _MemoryRecorder()
+        mw = TelemetryMW(TelemetryEmitter(rec))
+
+        async def terminal(request):
+            raise RequestRejectedError("400")
+
+        with pytest.raises(RequestRejectedError):
+            await mw(_REQ, terminal)
+        assert rec.rows == []
+
+
+def test_single_emitter_discipline():
+    """铁律执法: record_llm_call 在 src/ 的调用点只允许出现在 telemetry emitter。"""
+    out = subprocess.run(
+        ["grep", "-rln", "record_llm_call(", "src/polygateway"],
+        capture_output=True, text=True, cwd=Path(__file__).resolve().parents[2],
+    ).stdout.splitlines()
+    callers = [
+        p for p in out
+        if not p.endswith(("ports.py", "telemetry/sqlite.py"))
+    ]
+    assert callers == ["src/polygateway/middleware/telemetry.py"]