wip: 客服Agent + RAG + 画像收尾（基于 6516ccb）

tests/unit/service/test_model_gateway.py

@@ -73,3 +73,77 @@ async def test_gateway_missing_secret_and_empty_route_fail_closed(monkeypatch) -
             endpoint_code="primary", prompt="hello", timeout_ms=1000)
     with pytest.raises(RecoverableAgentError, match="没有可用"):
         await ModelGenerationService(ModelDispatchService(Gateway())).generate([], "hello")
+
+
+# ---------------------------------------------------------------------------
+# `DatabaseModelEndpointResolver` 按 task_type 过滤能力（补上被漏掉的契约兑现）
+# ---------------------------------------------------------------------------
+
+
+class _FakeScalarSession:
+    """只实现 `scalars()`：解析器只用它取 active 端点列表。"""
+
+    def __init__(self, rows: list[object]) -> None:
+        self._rows = rows
+
+    async def scalars(self, _statement: object) -> list[object]:
+        return self._rows
+
+    async def __aenter__(self) -> "_FakeScalarSession":
+        return self
+
+    async def __aexit__(self, *args: object) -> None:
+        return None
+
+
+def _endpoint(code: str, capabilities: list[str] | None) -> SimpleNamespace:
+    return SimpleNamespace(endpoint_code=code, capabilities=capabilities)
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    ("task_type", "expected"),
+    [
+        # 向量化只能走声明 embedding 的端点：交给 chat 端点会打到 /chat/completions 上。
+        ("embedding", ["embedding-primary"]),
+        # 生成与意图分类都走 chat 端点：交给 embedding 端点会 404。
+        ("chat", ["chat-primary"]),
+        ("intent_classification", ["chat-primary"]),
+        # 未知任务类型无法判断该要哪种能力 → 不过滤（返回全部 active）。
+        ("something_new", ["embedding-primary", "chat-primary"]),
+    ],
+)
+async def test_resolve_filters_endpoints_by_task_type_capability(
+    monkeypatch: pytest.MonkeyPatch, task_type: str, expected: list[str]
+) -> None:
+    """必须按 `task_type` 过滤能力。
+
+    不过滤的后果：`ModelDispatchService` 的 `generate`/`embed` 只取前
+    `max(1, max_attempts)`（默认 2）个端点，错叫一个就吃掉一次尝试机会 ——
+    端点一多会直接耗尽尝试而失败（原实现 `del agent_type, task_type` 即此缺陷）。
+    """
+    from app.service import model_gateway
+
+    rows = [_endpoint("embedding-primary", ["embedding"]), _endpoint("chat-primary", ["chat"])]
+    monkeypatch.setattr(model_gateway, "SessionFactory", lambda: _FakeScalarSession(rows))
+
+    resolved = await model_gateway.DatabaseModelEndpointResolver().resolve(
+        agent_type="customer_service", task_type=task_type
+    )
+    assert [e.endpoint_code for e in resolved] == expected
+
+
+@pytest.mark.asyncio
+async def test_resolve_skips_endpoints_without_declared_capabilities(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """`capabilities` 为 NULL/空 的端点不得被任何筛选选中（不能裸奔到错误的网关方法上）。"""
+    from app.service import model_gateway
+
+    rows = [_endpoint("broken", None), _endpoint("empty", []), _endpoint("chat-primary", ["chat"])]
+    monkeypatch.setattr(model_gateway, "SessionFactory", lambda: _FakeScalarSession(rows))
+
+    resolved = await model_gateway.DatabaseModelEndpointResolver().resolve(
+        agent_type="customer_service", task_type="chat"
+    )
+    assert [e.endpoint_code for e in resolved] == ["chat-primary"]