Laravel Passport - How to login via webapp?

I've set up a central app (let's call this maindomain.com), where I've setup Passport. This site will be where users register to gain access to all other apps I create.

To test it out, I've followed Matt Stauffer's blog post to create a client app that will use the user data stored on maindomain.com, let's call this app1.com.

I can confirm that my callback and whatnot work fine. When you go to app1.com/login (as per my route) it redirects to maindomain.com and allows you to authorise app1.com to use your login details - beautiful.

As per Matt's post, right now it prints the token to the screen. I need to change this so that it saves to the database - I assume I should just create a column on my user's table and store it there?

I've tested the token and can access the API routes using Postman. However, because at the moment I'm creating web apps that all need to use this centralised user system, I'm not sure how I can use a login form to authorise users and allow them access to their dashboard.

If user's are logging into app1.com do I send a POST request to maindomain.com? Isn't that going to be a problem with CSRF? I've read the documentation but as this is my first venture into Oauth2 I am pretty confused.

via Chebli Mohamed