Initialize each connection of a connection pool

[mkleen]

Hello,

I want to initialize each connection of my pool with a specific request to set server settings. If I override _create_connection from BaseConnector I can control the connection creation:

    async def _create_connection(self, req: ClientRequest, traces: List["Trace"], timeout: "ClientTimeout") -> ResponseHandler:
        
        transport, proto = await self._create_direct_connection(req, traces, timeout)
        
        return proto

How can I send a request to the newly created connection? Should i create a ClientSession inside _create_connection and post the request then? Is there a better way of doing this?

[Dreamsorcerer]

I'm not clear what you're trying to achieve, but I think you should be passing your custom connector to the ClientSession.

[mkleen]

I want to send a post request exactly once for each connection created. Once i created a ClientSession the connection pool is hidden and i can not distinguish the connections anymore.

[Dreamsorcerer]

You want to send a request in response to a connection being created, or you want a connection to be used for a single request only and then closed?

[mkleen]

I want to send a request in response to a connection being created.

[Dreamsorcerer]

Sounds like you want tracing. Glancing at the documentation, you want to use on_connection_create_end:
https://docs.aiohttp.org/en/stable/tracing_reference.html#aiohttp.TraceRequestStartParams

[mkleen]

Thanks a lot for the help. I will look into this.