Feature Request: Support AWS IAM and Token-Based Auth for AsyncPostgresSaver

[jcavejr]

I’m deploying LangGraph in an AWS environment using RDS for Postgres, where authentication is handled via IAM database authentication. This uses short-lived tokens that are generated through the AWS SDK and expire after 15 minutes.

Currently, AsyncPostgresSaver.from_conn_string() expects a static connection string, which doesn’t work well in this setup. There’s no clean way to plug in a dynamic credential source or periodically refresh tokens without managing the underlying asyncpg pool and reconnect logic ourselves.

Has there been any discussion around supporting dynamic or token-based authentication in database checkpointers? I’d love to find a way to make this work cleanly within LangGraph. Happy to share details about how IAM token auth works or what a minimal integration might look like if helpful.