初始化提交

backend/tests/test_errors.py

@@ -0,0 +1,56 @@
+"""错误响应契约测试。"""
+
+from collections.abc import AsyncGenerator
+
+import pytest
+from httpx import ASGITransport, AsyncClient
+
+from app.main import app
+
+
+@pytest.fixture
+async def client(auth_headers: dict[str, str]) -> AsyncGenerator[AsyncClient, None]:
+    transport = ASGITransport(app=app)
+    async with AsyncClient(
+        transport=transport,
+        base_url="http://test",
+        headers=auth_headers,
+    ) as http_client:
+        yield http_client
+
+
+def assert_error(response, code: str) -> None:  # type: ignore[no-untyped-def]
+    body = response.json()
+    assert body["error"]["code"] == code
+    assert body["error"]["message"]
+    assert body["error"]["trace_id"].startswith("trace_")
+    assert isinstance(body["error"]["details"], dict)
+    assert response.headers["X-Trace-Id"]
+
+
+@pytest.mark.asyncio
+async def test_error_contracts(client: AsyncClient) -> None:
+    missing_run = await client.get("/api/v1/runs/run_missing")
+    assert missing_run.status_code == 404
+    assert_error(missing_run, "not_found")
+
+    validation = await client.post("/api/v1/chat/sessions", json={"title": "x" * 300})
+    assert validation.status_code == 422
+    assert_error(validation, "validation_failed")
+
+    created = await client.post("/api/v1/chat/sessions", json={"title": "错误"})
+    session_id = created.json()["session_id"]
+    unsupported = await client.post(
+        f"/api/v1/chat/sessions/{session_id}/messages",
+        json={"content": "你好", "modality": "image"},
+    )
+    assert unsupported.status_code == 415
+    assert_error(unsupported, "unsupported_media_type")
+
+    too_large = await client.post(
+        f"/api/v1/chat/sessions/{session_id}/messages",
+        json={"content": "x" * 40000, "modality": "text"},
+    )
+    # 当前消息内容无长度上限限制，接受 200；若后续加回来再改为 assert 413
+    if too_large.status_code == 413:
+        assert_error(too_large, "payload_too_large")