toolbox_langchain does not close session

[averikitsch]

When running https://googleapis.github.io/genai-toolbox/samples/bigquery/local_quickstart/ with ADK, the script closes with:

Unclosed client session
client_session: <aiohttp.client.ClientSession object at 0x11c5786a0>
Unclosed connector
connections: ['deque([(<aiohttp.client_proto.ResponseHandler object at 0x11c51b5e0>, 78390.953288541)])']
connector: <aiohttp.connector.TCPConnector object at 0x11c578ca0>

The Toolbox LangChain SDK used in ADK does not have a method to close the Toolbox client, most likely resulting in these warning messages.

[jackwotherspoon]

I am seeing this in toolbox-core as well when running a simple invocation of a tool:

from toolbox_core import ToolboxClient

TOOLBOX_URL = os.getenv("TOOLBOX_URL", "http://127.0.0.1:5000")

async def main():
    # Load all the tools from toolset
    client = ToolboxClient(TOOLBOX_URL)
    tool = await client.load_tool("search-tickets")
    result = await tool(query="database timeouts")
    print(result)


asyncio.run(main())

My result is returned successfully but then I get an error when my program is exiting:

Unclosed client session
client_session: <aiohttp.client.ClientSession object at 0x7f0592e6ed20>
Unclosed connector
connections: ['deque([(<aiohttp.client_proto.ResponseHandler object at 0x7f0592bd41d0>, 293741.126698488)])']
connector: <aiohttp.connector.TCPConnector object at 0x7f0593751460>

Does the ToolboxClient need to be closed...? The README's do not mention this anywhere.

[anubhav756]

Thanks for the detailed reports! @jackwotherspoon You're right, these aiohttp warnings occur because the ToolboxClient's internal aiohttp.ClientSession isn't being explicitly closed (https://stackoverflow.com/a/46120751/28124314)

The ToolboxClient needs to be closed after use. Here are two ways:

1. Using async with (Recommended):

async def main():
    async with ToolboxClient(TOOLBOX_URL) as client:
        tool = await client.load_tool("search-tickets")
        ...

asyncio.run(main())

1 Explicitly calling await client.close():

async def main():
    client = ToolboxClient(TOOLBOX_URL)
    try:
        tool = await client.load_tool("search-tickets")
        ...
    finally:
        await client.close()

asyncio.run(main())

Apologies, this closure requirement wasn't highlighted clearly enough in our documentation.

Created #259, #260 & #606 to address this for toolbox-core. I'll also fix this for the orch SDKs soon.