OAuth & Access Token Persist Question

I'm new to OAuth and I'm mostly done implementing OAuth against Facebook and Twitter.

The way my application works is user can sign on either through Facebook or Twitter. Once getting in, they can setup the other, i.e if they log in using twitter, I ask them to setup facebook wall and if they sign up using facebook, then I ask them to setup their twitter.

The issue I have is this. Users after signing out and come back again, how do I avoid them to setup the things again? I not开发者_运维知识库iced twitter access token never expires, so I guess that solve this side of the issue. But Facebook access token does expire. It's very inconvenient to ask my users to sign into facebook everytime to have that part of the application to work.

I might understood this whole thing wrong, so any suggestion is greatly appreciate it.

As far as I remember Facebook (https://graph.facebook.com/oauth/authorize?...) returns back user immediately if user has previously approved your application, so that he/she won't notice it if you design your app flow correctly (for example you can redirect user to Facebook in a popup and close popup when user returns back).