Error: OAuth 2.0 authentication requires session support when using state

[enbochen]

When running the example, it comes up with this error:
Error: OAuth 2.0 authentication requires session support when using state. Did you forget to use express-session middleware?

[ghost]

Hi aprilsnows,
Just install the express-session npm and placed into your server file.
// Linkedin needed express session
var session = require('express-session');
app.use(session({ secret: 'SECRET' }));