google-auth-hook.js

const {User, AuthenticationRequired) = require('unleash-server');

const passport = require('passport');
const GoogleOAuth2Strategy = require('passport-google-auth').Strategy;

passport.use(
    new GoogleOAuth2Strategy(
        {
            clientId: process.env.GOOGLE_CLIENT_ID,
            clientSecret: process.env.GOOGLE_CLIENT_SECRET,
            callbackURL: process.env.GOOGLE_CALLBACK_URL,
        },

        (accessToken, refreshToken, profile, done) => {
            done(
                null,
                new User({
                    name: profile.displayName,
                    email: profile.emails[0].value,
                })
            );
        }
    )
);

function enableGoogleOauth(app) {
    app.use(passport.initialize());
    app.use(passport.session());

    passport.serializeUser((user, done) => done(null, user));
    passport.deserializeUser((user, done) => done(null, user));
    app.get('/api/admin/login', passport.authenticate('google'));

    app.get(
        '/api/auth/callback',
        passport.authenticate('google', {
            failureRedirect: '/api/admin/error-login',
        }),
        (req, res) => {
            // Successful authentication, redirect to your app.
            res.redirect('/');
        }
    );

    app.use('/api/admin/', (req, res, next) => {
        if (req.user) {
            next();
        } else {
            // Instruct unleash-frontend to pop-up auth dialog
            return res
                .status('401')
                .json(
                    new AuthenticationRequired({
                        path: '/api/admin/login',
                        type: 'custom',
                        message: `You have to identify yourself in order to use Unleash. 
                        Click the button and follow the instructions.`,
                    })
                )
                .end();
        }
    });
}

module.exports = enableGoogleOauth;

my-unleash-server.js

const unleash = require('unleash-server');
const enableGoogleOauth = require('./google-auth-hook');

unleash.start({
  databaseUrl: 'postgres://unleash_user:passord@localhost:5432/unleash',
  secret: 'super-duper-secret',
  adminAuthentication: 'custom',
  preRouterHook: enableGoogleOauth
}).then(unleash => {
    console.log(`Unleash started on http://localhost:${unleash.app.get('port')}`);
});

hb

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