Contacts Store Application JavaScript

contactsApp.js

//create firebase reference
var dbRef = new Firebase("https://contactb.firebaseio.com/");
var contactsRef = dbRef.child('contacts')

//load older conatcts as well as any newly added one...
contactsRef.on("child_added", function(snap) {
  console.log("added", snap.key(), snap.val());
  document
    .querySelector('#contacts')
    .innerHTML += contactHtmlFromObject(snap.val());
});

//save contact
document
  .querySelector('.addValue')
  .addEventListener("click", function( event ) {  
    event.preventDefault();
    if( document.querySelector('#name').value != '' 
          || document.querySelector('#email').value != '' ){
      contactsRef
        .push({
          name: document.querySelector('#name').value,
          email: document.querySelector('#email').value,
          location: {
            city: document.querySelector('#city').value,
            state: document.querySelector('#state').value,
            zip: document.querySelector('#zip').value
          }
        })
        contactForm.reset();
    } else {
      alert('Please fill atlease name or email!');
    }
  }, false);

//prepare conatct object's HTML
function contactHtmlFromObject(contact){
  console.log( contact );
  var html = '';
  html += '<li class="list-group-item contact">';
    html += '<div>';
      html += '<p class="lead">'+contact.name+'</p>';
      html += '<p>'+contact.email+'</p>';
      html += '<p><small title="'
                +contact.location.zip+'">'
                +contact.location.city
                +', '
                +contact.location.state
                +'</small></p>';
    html += '</div>';
  html += '</li>';
  return html;
}