authenticate.js

var passport = require('passport');
var LocalStartegy = require('passport-local').Strategy; 
var User = require('./models/users');
var JwtStrategy = require('passport-jwt').Strategy;
var ExtractJwt = require('passport-jwt').ExtractJwt;
var jwt = require('jsonwebtoken');

var config = require('./config');

exports.local = passport.use(new LocalStartegy(User.authenticate())); // if you dont use passprt-local-mongoose you need to write your own authentificate function
// Taking care of session support
passport.serializeUser(User.serializeUser());
passport.deserializeUser(User.deserializeUser());

exports.getToken = function(user) {
    return jwt.sign(user, config.secretKey, 
        { expiresIn: 604800 }); // time to re authenticate // 604800
};

var opts = {};
opts.jwtFromRequest = ExtractJwt.fromAuthHeaderAsBearerToken(); // carry token in header
opts.secretOrKey = config.secretKey;

exports.jwtPassport = passport.use(new JwtStrategy(opts,
    (jwt_payload, done) => {
        console.log("JWT payload: ", jwt_payload)
        User.findOne({_id: jwt_payload._id}, (err, user) => {
            if (err) {
                return done(err, false); // done is callback func that passport passes
            }
            else if (user) {
                return done(null, user);
            }
            else {
                return done(null, false);
            }
        });
    }));


exports.verifyUser = passport.authenticate('jwt', {session: false}); // jwt strategy just configered // token based auth so no sessions created

exports.verifySupervisor = function(req, res, next) {
    if (req.user.supervisor) {
        next();
    }
    else {
        err = new Error('You are not authorized to perform this operation!');
        err.status = 403;
        return next(err);
    }     
}

exports.verifyAdmin = function(req, res, next) {
    if (req.user.admin) {
        next();
    }
    else {
        err = new Error('You are not authorized to perform this operation!');
        err.status = 403;
        return next(err);
    }     
}