var dummyReq = { client: null };
var dummyUser = { email: 'user@secretdomain.com', password: 'admin' };

function printEmail(request, user) {
    return new Promise((resolve, reject) => {
        console.log('Email:', user.email);
        return resolve(request, user);
    });
}

function printPassword(request, user) {
    return new Promise((resolve, reject) => {
        console.log('Password:', user.password); // <-- user is undefined
        return resolve(request, user);
    });
}

printEmail(dummyReq, dummyUser)
    .then(printPassword)
    .catch(function(error) {
    console.log('Unexepected error has occured');
});