freeCodeCamp/config/passport.js

var _ = require('lodash');
var passport = require('passport');
var InstagramStrategy = require('passport-instagram').Strategy;
var LocalStrategy = require('passport-local').Strategy;
var FacebookStrategy = require('passport-facebook').Strategy;
var TwitterStrategy = require('passport-twitter').Strategy;
var GitHubStrategy = require('passport-github').Strategy;
var GoogleStrategy = require('passport-google-oauth').OAuth2Strategy;
var LinkedInStrategy = require('passport-linkedin-oauth2').Strategy;
var OAuthStrategy = require('passport-oauth').OAuthStrategy; // Tumblr
var OAuth2Strategy = require('passport-oauth').OAuth2Strategy; // Venmo, Foursquare
var User = require('../models/User');
var secrets = require('./secrets');

passport.serializeUser(function(user, done) {
    done(null, user.id);
});

passport.deserializeUser(function(id, done) {
    User.findById(id, function(err, user) {
        done(err, user);
    });
});

// Sign in with Instagram.

passport.use(new InstagramStrategy(secrets.instagram,function(req, accessToken, refreshToken, profile, done) {
    if (req.user) {
        User.findOne({ instagram: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already an Instagram account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.instagram = profile.id;
                    user.tokens.push({ kind: 'instagram', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.picture = user.profile.picture || profile._json.data.profile_picture;
                    user.profile.website = user.profile.website || profile._json.data.website;
                    user.save(function(err) {
                        req.flash('info', { msg: 'Instagram account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });
    } else {
        User.findOne({ instagram: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);

            var user = new User();
            user.instagram = profile.id;
            user.tokens.push({ kind: 'instagram', accessToken: accessToken });
            user.profile.name = profile.displayName;
            // Similar to Twitter API, assigns a temporary e-mail address
            // to get on with the registration process. It can be changed later
            // to a valid e-mail address in Profile Management.
            user.email = profile.username + "@instagram.com";
            user.profile.website = profile._json.data.website;
            user.profile.picture = profile._json.data.profile_picture;
            user.save(function(err) {
                done(err, user);
            });
        });
    }
}));

// Sign in using Email and Password.

passport.use(new LocalStrategy({ usernameField: 'email' }, function(email, password, done) {
    User.findOne({ email: email }, function(err, user) {
        if (!user) return done(null, false, { message: 'Email ' + email + ' not found'});
        user.comparePassword(password, function(err, isMatch) {
            if (isMatch) {
                return done(null, user);
            } else {
                return done(null, false, { message: 'Invalid email or password.' });
            }
        });
    });
}));

/**
 * OAuth Strategy Overview
 *
 * - User is already logged in.
 *   - Check if there is an existing account with a <provider> id.
 *     - If there is, return an error message. (Account merging not supported)
 *     - Else link new OAuth account with currently logged-in user.
 * - User is not logged in.
 *   - Check if it's a returning user.
 *     - If returning user, sign in and we are done.
 *     - Else check if there is an existing account with user's email.
 *       - If there is, return an error message.
 *       - Else create a new account.
 */

// Sign in with Facebook.

passport.use(new FacebookStrategy(secrets.facebook, function(req, accessToken, refreshToken, profile, done) {
    if (req.user) {
        User.findOne({ facebook: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already a Facebook account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.facebook = profile.id;
                    user.tokens.push({ kind: 'facebook', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.gender = user.profile.gender || profile._json.gender;
                    user.profile.picture = user.profile.picture || 'https://graph.facebook.com/' + profile.id + '/picture?type=large';
                    user.save(function(err) {
                        req.flash('info', { msg: 'Facebook account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });
    } else {
        User.findOne({ facebook: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);
            User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with Facebook manually from Account Settings.' });
                    done(err);
                } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.facebook = profile.id;
                    user.tokens.push({ kind: 'facebook', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.gender = profile._json.gender;
                    user.profile.picture = 'https://graph.facebook.com/' + profile.id + '/picture?type=large';
                    user.profile.location = (profile._json.location) ? profile._json.location.name : '';
                    user.save(function(err) {
                        done(err, user);
                    });
                }
            });
        });
    }
}));

// Sign in with GitHub.

passport.use(new GitHubStrategy(secrets.github, function(req, accessToken, refreshToken, profile, done) {
    if (req.user) {
        User.findOne({ github: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already a GitHub account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.github = profile.id;
                    user.tokens.push({ kind: 'github', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.picture = user.profile.picture || profile._json.avatar_url;
                    user.profile.location = user.profile.location || profile._json.location;
                    user.profile.website = user.profile.website || profile._json.blog;
                    user.save(function(err) {
                        req.flash('info', { msg: 'GitHub account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });
    } else {
        User.findOne({ github: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);
            User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with GitHub manually from Account Settings.' });
                    done(err);
                } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.github = profile.id;
                    user.tokens.push({ kind: 'github', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.picture = profile._json.avatar_url;
                    user.profile.location = profile._json.location;
                    user.profile.website = profile._json.blog;
                    user.save(function(err) {
                        done(err, user);
                    });
                }
            });
        });
    }
}));

// Sign in with Twitter.

passport.use(new TwitterStrategy(secrets.twitter, function(req, accessToken, tokenSecret, profile, done) {
    if (req.user) {
        User.findOne({ twitter: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already a Twitter account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.twitter = profile.id;
                    user.tokens.push({ kind: 'twitter', accessToken: accessToken, tokenSecret: tokenSecret });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.location = user.profile.location || profile._json.location;
                    user.profile.picture = user.profile.picture || profile._json.profile_image_url_https;
                    user.profile.username = profile.username;
                    user.save(function(err) {
                        req.flash('info', { msg: 'Twitter account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });

    } else {
        User.findOne({ twitter: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);
            var user = new User();
            // Twitter will not provide an email address.  Period.
            // But a person’s twitter username is guaranteed to be unique
            // so we can "fake" a twitter email address as follows:
            user.email = profile.username + "@twitter.com";
            user.twitter = profile.id;
            user.tokens.push({ kind: 'twitter', accessToken: accessToken, tokenSecret: tokenSecret });
            user.profile.name = profile.displayName;
            user.profile.location = profile._json.location;
            user.profile.picture = profile._json.profile_image_url_https;
            user.save(function(err) {
                done(err, user);
            });
        });
    }
}));

// Sign in with Google.

passport.use(new GoogleStrategy(secrets.google, function(req, accessToken, refreshToken, profile, done) {
    if (req.user) {
        User.findOne({ google: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already a Google account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.google = profile.id;
                    user.tokens.push({ kind: 'google', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.gender = user.profile.gender || profile._json.gender;
                    user.profile.picture = user.profile.picture || profile._json.picture;
                    user.save(function(err) {
                        req.flash('info', { msg: 'Google account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });
    } else {
        User.findOne({ google: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);
            User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with Google manually from Account Settings.' });
                    done(err);
                } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.google = profile.id;
                    user.tokens.push({ kind: 'google', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.gender = profile._json.gender;
                    user.profile.picture = profile._json.picture;
                    user.save(function(err) {
                        done(err, user);
                    });
                }
            });
        });
    }
}));

// Sign in with LinkedIn.

passport.use(new LinkedInStrategy(secrets.linkedin, function(req, accessToken, refreshToken, profile, done) {
    if (req.user) {
        User.findOne({ linkedin: profile.id }, function(err, existingUser) {
            if (existingUser) {
                req.flash('errors', { msg: 'There is already a LinkedIn account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                done(err);
            } else {
                User.findById(req.user.id, function(err, user) {
                    user.linkedin = profile.id;
                    user.tokens.push({ kind: 'linkedin', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.location = user.profile.location || profile._json.location.name;
                    user.profile.picture = user.profile.picture || profile._json.pictureUrl;
                    user.profile.website = user.profile.website || profile._json.publicProfileUrl;
                    user.save(function(err) {
                        req.flash('info', { msg: 'LinkedIn account has been linked.' });
                        done(err, user);
                    });
                });
            }
        });
    } else {
        User.findOne({ linkedin: profile.id }, function(err, existingUser) {
            if (existingUser) return done(null, existingUser);
            User.findOne({ email: profile._json.emailAddress }, function(err, existingEmailUser) {
                if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with LinkedIn manually from Account Settings.' });
                    done(err);
                } else {
                    var user = new User();
                    user.linkedin = profile.id;
                    user.tokens.push({ kind: 'linkedin', accessToken: accessToken });
                    user.email = profile._json.emailAddress;
                    user.profile.name = profile.displayName;
                    user.profile.location = profile._json.location.name;
                    user.profile.picture = profile._json.pictureUrl;
                    user.profile.website = profile._json.publicProfileUrl;
                    user.save(function(err) {
                        done(err, user);
                    });
                }
            });
        });
    }
}));

// Tumblr API setup.

passport.use('tumblr', new OAuthStrategy({
        requestTokenURL: 'http://www.tumblr.com/oauth/request_token',
        accessTokenURL: 'http://www.tumblr.com/oauth/access_token',
        userAuthorizationURL: 'http://www.tumblr.com/oauth/authorize',
        consumerKey: secrets.tumblr.consumerKey,
        consumerSecret: secrets.tumblr.consumerSecret,
        callbackURL: secrets.tumblr.callbackURL,
        passReqToCallback: true
    },
    function(req, token, tokenSecret, profile, done) {
        User.findById(req.user._id, function(err, user) {
            user.tokens.push({ kind: 'tumblr', accessToken: token, tokenSecret: tokenSecret });
            user.save(function(err) {
                done(err, user);
            });
        });
    }
));

// Foursquare API setup.

passport.use('foursquare', new OAuth2Strategy({
        authorizationURL: 'https://foursquare.com/oauth2/authorize',
        tokenURL: 'https://foursquare.com/oauth2/access_token',
        clientID: secrets.foursquare.clientId,
        clientSecret: secrets.foursquare.clientSecret,
        callbackURL: secrets.foursquare.redirectUrl,
        passReqToCallback: true
    },
    function(req, accessToken, refreshToken, profile, done) {
        User.findById(req.user._id, function(err, user) {
            user.tokens.push({ kind: 'foursquare', accessToken: accessToken });
            user.save(function(err) {
                done(err, user);
            });
        });
    }
));

// Venmo API setup.

passport.use('venmo', new OAuth2Strategy({
        authorizationURL: 'https://api.venmo.com/v1/oauth/authorize',
        tokenURL: 'https://api.venmo.com/v1/oauth/access_token',
        clientID: secrets.venmo.clientId,
        clientSecret: secrets.venmo.clientSecret,
        callbackURL: secrets.venmo.redirectUrl,
        passReqToCallback: true
    },
    function(req, accessToken, refreshToken, profile, done) {
        User.findById(req.user._id, function(err, user) {
            user.tokens.push({ kind: 'venmo', accessToken: accessToken });
            user.save(function(err) {
                done(err, user);
            });
        });
    }
));

// Login Required middleware.

exports.isAuthenticated = function(req, res, next) {
    if (req.isAuthenticated()) return next();
    res.redirect('/login');
};

// Authorization Required middleware.

exports.isAuthorized = function(req, res, next) {
    var provider = req.path.split('/').slice(-1)[0];

    if (_.find(req.user.tokens, { kind: provider })) {
        next();
    } else {
        res.redirect('/auth/' + provider);
    }
};