Predicament online web state within the back of a login for every user securely without storing their credentials

Hello swish stumbled on this subreddit belief I'd give it a bolt!

I’m pondering constructing an app which is ready to connect with lots of of my customers’ third social gathering accounts on various websites which don’t have an API that I’m going to must spot periodically.

I’m wondering what basically the most elementary formula to enact something esteem this is from a security perspective. I don’t are looking to be storing the credentials of the user for a set I don’t operate. How then can i pull spot files from their logged in web state? What's simplest observe around this form of anguish?