register() {
    var email = '';
    var password = '';

    this.firebase.auth().createUserWithEmailAndPassword(email, password)
      .then(function (response) {
        // successful register
      })
      .catch(function (e) {
        // register failure
      })
  }

/***************************************************************/

  login() {
    var email = '';
    var password = '';

    this.firebase.auth().signInWithEmailAndPassword(email, password)
      .then(function (response) {
        // success
      })
      .catch(function () {
        // failure
      });
  }



/***************************************************************/
// get current auth user

var user = firebase.auth().currentUser;

if (user) {
  // User is signed in.
} else {
  // No user is signed in.
}