feat(BA-4538): Add System version info to Client SDK v2 (#9060)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: HyeockJinKim

changes/9060.feature.md

@@ -0,0 +1 @@
+Add System version info client (`SystemClient.get_versions()`) to Client SDK v2

src/ai/backend/client/v2/domains/system.py

@@ -0,0 +1,15 @@
+from __future__ import annotations
+
+from ai.backend.client.v2.base_domain import BaseDomainClient
+from ai.backend.common.dto.manager.system import SystemVersionResponse
+
+
+class SystemClient(BaseDomainClient):
+    """Client for system version info endpoint."""
+
+    async def get_versions(self) -> SystemVersionResponse:
+        return await self._client.typed_request(
+            "GET",
+            "/",
+            response_model=SystemVersionResponse,
+        )

src/ai/backend/client/v2/registry.py

@@ -35,6 +35,7 @@
     from .domains.session import SessionClient
     from .domains.storage import StorageClient
     from .domains.streaming import StreamingClient
+    from .domains.system import SystemClient
     from .domains.template import TemplateClient
     from .domains.vfolder import VFolderClient
 
@@ -230,3 +231,9 @@ def compute_session(self) -> ComputeSessionClient:
         from .domains.compute_session import ComputeSessionClient
 
         return ComputeSessionClient(self._client)
+
+    @cached_property
+    def system(self) -> SystemClient:
+        from .domains.system import SystemClient
+
+        return SystemClient(self._client)

src/ai/backend/common/dto/manager/system/__init__.py

@@ -0,0 +1,7 @@
+from __future__ import annotations
+
+from .response import (
+    SystemVersionResponse,
+)
+
+__all__ = ("SystemVersionResponse",)

src/ai/backend/common/dto/manager/system/response.py

@@ -0,0 +1,14 @@
+from __future__ import annotations
+
+from pydantic import Field
+
+from ai.backend.common.api_handlers import BaseResponseModel
+
+__all__ = ("SystemVersionResponse",)
+
+
+class SystemVersionResponse(BaseResponseModel):
+    """Response for system version info from GET /."""
+
+    version: str = Field(description="API version string")
+    manager: str = Field(description="Manager version string")

tests/unit/client_v2/test_system_client.py

@@ -0,0 +1,81 @@
+from typing import Any
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+from yarl import URL
+
+from ai.backend.client.v2.base_client import BackendAIClient
+from ai.backend.client.v2.config import ClientConfig
+from ai.backend.client.v2.domains.system import SystemClient
+from ai.backend.common.dto.manager.system import SystemVersionResponse
+
+from .conftest import MockAuth
+
+_DEFAULT_CONFIG = ClientConfig(endpoint=URL("https://api.example.com"))
+
+
+def _make_client(
+    mock_session: MagicMock | None = None,
+    config: ClientConfig | None = None,
+) -> BackendAIClient:
+    return BackendAIClient(
+        config or _DEFAULT_CONFIG,
+        MockAuth(),
+        mock_session or MagicMock(),
+    )
+
+
+def _make_request_session(resp: AsyncMock) -> MagicMock:
+    """Build a mock session whose ``request()`` returns *resp* as a context manager."""
+    mock_ctx = AsyncMock()
+    mock_ctx.__aenter__ = AsyncMock(return_value=resp)
+    mock_ctx.__aexit__ = AsyncMock(return_value=False)
+
+    mock_session = MagicMock()
+    mock_session.request = MagicMock(return_value=mock_ctx)
+    return mock_session
+
+
+def _ok_response(data: dict[str, Any]) -> AsyncMock:
+    mock_resp = AsyncMock()
+    mock_resp.status = 200
+    mock_resp.json = AsyncMock(return_value=data)
+    return mock_resp
+
+
+class TestSystemClient:
+    @pytest.mark.asyncio
+    async def test_get_versions(self) -> None:
+        mock_resp = _ok_response({
+            "version": "v9.20250722",
+            "manager": "25.3.0",
+        })
+        mock_session = _make_request_session(mock_resp)
+        client = _make_client(mock_session)
+        system = SystemClient(client)
+
+        result = await system.get_versions()
+
+        assert isinstance(result, SystemVersionResponse)
+        assert result.version == "v9.20250722"
+        assert result.manager == "25.3.0"
+
+        call_args = mock_session.request.call_args
+        assert call_args.args[0] == "GET"
+        assert str(call_args.args[1]).endswith("/")
+
+    @pytest.mark.asyncio
+    async def test_get_versions_different_values(self) -> None:
+        mock_resp = _ok_response({
+            "version": "v8.20240315",
+            "manager": "24.1.0",
+        })
+        mock_session = _make_request_session(mock_resp)
+        client = _make_client(mock_session)
+        system = SystemClient(client)
+
+        result = await system.get_versions()
+
+        assert isinstance(result, SystemVersionResponse)
+        assert result.version == "v8.20240315"
+        assert result.manager == "24.1.0"