Question

If I have already authenticated a user via OpenID, and they are redirected back to Magento, how do I log them in automatically? All I have is their email. What am I missing?

Thanks in advance.

Answer 1

It is answer to question how to login customer in, not to initial big question. I decided to write it here because code formatting is absent in comments.

// $login here is customer email
$customer = Mage::getModel('customer/customer')
    ->setWebsiteId(Mage::app()->getStore()->getWebsiteId())
    ->loadByEmail($login);

Mage::getSingleton('customer/session')->setCustomerAsLoggedIn($customer)
    ->renewSession();

// now redirect user to home page or do something else what you need