Implementing a secure social media access through a third party web application's user account profile

Question

I am working within a web application where there are user accounts with their associated profile pages. I would like to add three links on the user's profile page linking them to their associated Facebook, Twitter, and LinkedIn accounts via their profile page. I would also like to implement a secure way for user credentials to be stored locally so that they don't have to login to these services (Facebook, Twitter, LinkedIn) manually each time they enter their profile within my web application. What do you think is the best way to,

1- Implement the social media contents over the running account profile. 2- Securely store user's credentials locally to automatically login to any of the social media once they login to their profile account on my website.

Many Thanks

Answer 1

You cannot log in for the user on a third party site. You cannot store their third party credentials and "help" them log in, unless the third party explicitly supports that through some API/authentication mechanism. Otherwise the user will always have to log into the third party site herself.

The other way around, Facebook/Twitter etc. offer an API which you can support to help the user log in to your site using the third party's credentials. This does not automatically work the other way around. You would have to offer an API which Facebook/Twitter would have to explicitly support to help users log in to their sites with credentials stored on your server.