Refresh token for vue-adal

I'm using vue.js to build a SPA and vue-adal to authenticate with Azure AD. Logging in works fine, but now I'm trying to keep the users logged in. I did some research and read that a refresh token would make this possible. I've read here that I have to create this functionality manually, but I can't really find anything useful about how to actually do that.

So how would I go on about refreshing my tokens in a SPA using vue.js / vue-adal?