angular-cog | declarative ajax requests for angularjs | REST library

If you are already getting your hands dirty managing your user data I would integrate directly with the social providers. Cognito is most useful as a cheap and dirty place store user data and to host managed authentication and authorization services. You are already storing your own user data and sounds like you are only supporting social login; Cognito might be more of hindrance in this situation.

Additonally, there isn't some magic that powers cognito social logins, you have to go through the same configuration steps if you were integrating directly, only difference is cognito will act as the callback endpoint.

But if you want to forge ahead while avoiding vendor lock-in use it strictly as an OIDC service provider and use a generic OIDC strategy with passport or just remove passport altogether as you don't really need it in this situation, then as auth0 recommends use the oidc express middleware to protect your endpoints and use something like AppAuth to get the access token in your frontend.