share aiohttp.ClientSession between clients

[adamko147]

According to documentation at https://docs.aiohttp.org/en/stable/client_reference.html#client-reference it's suggested to use single ClientSession for app

Session encapsulates a connection pool (connector instance) and supports keepalives by default. Unless you are connecting to a large, unknown number of different servers over the lifetime of your application, it is suggested you use a single session for the lifetime of your application to benefit from connection pooling.

Is there any way how to achieve sharing single ClientSession in aiobotocore accross multiple clients? I'm running multiple requests to AWS resources and each client uses own ClientSession.

Thanks

[dazza-codes]

My 2c - good question - but aiobotocore is kinda tied to botocore design patterns (AFAIK) and it has to stick with the patterns in aiobotocore.endpoint.AioEndpointCreator to instantiate the aiohttp.ClientSession on the endpoint_instance.http_session.

In botocore, if you want to try to override things by first creating a single client and then using it everywhere else (for a given AWS service, of course), you could register a handler for the create-client event. But aiobotocore is not using the same event registration/handler pattern for clients to ensure that it uses the aiohttp client (AFAICT).

Details are in

• aiobotocore.session.AioSession.create_client
• aiobotocore.endpoint.AioEndpointCreator

Some related notes on botocore that delve into how it constructs clients and connection pools is at https://gitlab.com/dazza-codes/aio-aws/-/wikis/botocore-clients

[adamko147]

Thanks @dazza-codes for your reply. I can see the pattern in botocore. Unless aiobotocore wants to strictly follow that, it would be interesting to find out how to share the http_session. maybe optional parameter to create_client or new create-aio-session event? I could try to do the work, if you think it's worth to try. Thanks

[dazza-codes]

See also #749 and #791 (using connection-args maybe)

[thehesiod]

aiobotocore follows botocore, which my default uses a session per client, however, it allows you to pass in your own session class, see https://github.com/boto/botocore/blob/develop/botocore/endpoint.py#L280 so you can try using that however it doesn't seemed to be hooked up all the way in botocore. Fixing a small bug of this in #844