Magento - check if customer attribute already exists - magento

Question

I have a custom module which is called on the customer_save_observer_executed event and specifically when a customer updates their details in their account page (name, password, email etc) I have added a custom attribute called display_name.
When a customer submits this form i need to check if the display_name currently exists for any other customer. If it doesn't then setDisplayName(...) else do nothing/display error message.
I was hoping to do this with this snippet:
$customer_check = Mage::getModel('customer/customer')
->getCollection()
->addAttributeToSelect('display_name')
->addAttributeToFilter('display_name',$new_name)->load();
if ( is_object($customer_check) && count($customer_check) >= 2) {
// dont allow - duplicate customer displayname
}
else {
// allow update....
}
My current code in Model -> Observer.php
class xxxxxxx_Model_Observer
{
public function xxxxxxxx(Varien_Event_Observer $observer)
{
// to stop event being fired twice
if(Mage::registry('customer_save_observer_executed')){
return $this;
}
$postData = Mage::app()->getRequest()->getPost();
$customer = $observer->getCustomer();
// if updating NOT a new customer
if($customer instanceof Mage_Customer_Model_Customer && !$customer->isObjectNew()) {
// check display name is posted
if(!empty($postData['display_name'])){
$current_name = $customer->getDisplayName();
$new_name = $postData['display_name'];
// duplicate check
$customer_check = Mage::getModel('customer/customer')
->getCollection()
->addAttributeToSelect('display_name')
->addAttributeToFilter('display_name',$new_name)->load();
if ( is_object($customer_check) && count($customer_check) >= 2) {
// dont allow - duplicate customer displayname
}
else {
if( $postData['display_name'] !== $current_name ) {
$customer->setDisplayName($postData['display_name']);
}
}
}
}
Mage::register('customer_save_observer_executed',true);
}
}
but this just updates the display_name even if i deliberately set it to a duplicate of another customers
UPDATE
Looking into this further it looks like the module function itself is not being run or nothing inside it is taking affect, as whatever i put in it doesn't work. It is infact the default behaviour that is setting the displayname not my module. My module is activated and my config file uses the customer_save_commit_after event as shown below:
<?xml version="1.0" encoding="UTF-8"?>
<config>
<modules>
<xxx_xxxxx>
<version>0.0.1</version>
</xxx_xxxxx>
</modules>
<global>
<models>
<xxx_xxxxx>
<class>xxx_xxxxx_Model</class>
</xxx_xxxxx>
</models>
<events>
<customer_save_commit_after>
<observers>
<xxx_xxxxx>
<class>xxx_xxxxx/observer</class>
<method>xxxxxx</method>
<type>singleton</type>
</xxx_xxxxx>
</observers>
</customer_save_commit_after>
</events>
</global>
</config>

Answer 1

This probably is the case because all data from the form submitted is set on the customer model in Magento's Customer module (code taken from Mage_Customer_AccountController)
/**
* Forgot customer account information page
*/
public function editAction()
{
$this->loadLayout();
$this->_initLayoutMessages('customer/session');
$this->_initLayoutMessages('catalog/session');
$block = $this->getLayout()->getBlock('customer_edit');
if ($block) {
$block->setRefererUrl($this->_getRefererUrl());
}
$data = $this->_getSession()->getCustomerFormData(true);
$customer = $this->_getSession()->getCustomer();
if (!empty($data)) {
$customer->addData($data);
}
if ($this->getRequest()->getParam('changepass') == 1) {
$customer->setChangePassword(1);
}
$this->getLayout()->getBlock('head')->setTitle($this->__('Account Information'));
$this->getLayout()->getBlock('messages')->setEscapeMessageFlag(true);
$this->renderLayout();
}
Here addData() is called on the customer model. To prevent this rename your form's input to something temporary, like <input name="display_name_tmp"/>, then in your controller do something like
public function xxxxxxxx(Varien_Event_Observer $observer)
{
// to stop event being fired twice
if(Mage::registry('customer_save_observer_executed')){
return $this;
}
$postData = Mage::app()->getRequest()->getPost();
$customer = $observer->getCustomer();
// if updating NOT a new customer
if($customer instanceof Mage_Customer_Model_Customer &&
!$customer->isObjectNew()) {
// check display name is posted
if(!empty($postData['display_name_tmp'])){
$current_name = $customer->getDisplayName();
$new_name = $postData['display_name_tmp'];
// duplicate check
$customer_check = Mage::getModel('customer/customer')
->getCollection()
->addAttributeToSelect('display_name')
->addAttributeToFilter('display_name',$new_name)->load();
if ( is_object($customer_check) && count($customer_check) >= 2) {
// dont allow - duplicate customer displayname
}
else {
if( $postData['display_name'] !== $current_name ) {
$customer->setDisplayName($postData['display_name_tmp']);
}
}
}
}
Mage::register('customer_save_observer_executed',true);
}