Magento 2: get customer id of logged in user with cache enabled

Question

I need to get the customer id of the user that is logged in. Using the following code it works fine for blocks where cache is disabled. But when there's a cached block on the page, it's null. Even if the customer is logged in. It is intended behavior for the customersession to be cleared when caching is active on a page but I need the customer id to show customer specific prices (B2B).

$customerSession = $objectManager->get('Magento\Customer\Model\Session');
if(!$customerSession->isLoggedIn()) {
    $customerId = $customerSession->getCustomer()->getId();
}

I need to be able to get the customer id on all pages where prices are displayed for products. So, for example, the category list/grid page and the product details page.

I have read countless of bug reports on github but they all get closed by Magento as if it's no issue.

Answer 1

I have updated my response. In my previous answer, I had a block cacheable=false. This is incorrect because it do the page is not cacheable.

For knowing if the customer is logged or not, you must do the next:

Namespace/Modulename/etc/di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\Customer\Model\Session">
         <plugin name="namespace_module_customer_plugin_session" type="Namespace\Modulename\Plugin\Customer\Model\Session"/>
    </type>
</config>

Namespace/Modulename/Plugin/Customer/Model/Session.php

<?php    
namespace Namespace\Modulename\Plugin\Customer\Model;

use Magento\Customer\Model\Context as CustomerContext;
use Magento\Customer\Model\Session as CustomerSession;
use Magento\Framework\App\Http\Context;

/**
 * Class Session
 */
class Session
{

    /**
     * @var Context
     */
    private $httpContext;

    /**
     * Session constructor.
     *
     * @param Context $context
     */
    public function __construct(
        Context $context
    ) {
        $this->httpContext = $context;
    }

    /**
     * Check http context to know if user is really logged in
     *
     * @param CustomerSession $subject
     * @param bool $isLoggedIn
     * @return bool
     */
    public function afterIsLoggedIn(CustomerSession $subject, $isLoggedIn)
    {
        return $isLoggedIn ?: $this->httpContext->getValue(CustomerContext::CONTEXT_AUTH);
    }
}

When you do $customerSession->isLoggedIn(), it will return the correct value.

To retrieve the id of the customer, the best way is how says @SohelRana in its comment, using ajax or private cache. https://devdocs.magento.com/guides/v2.2/extension-dev-guide/cache/page-caching/private-content.html

Answer 2

How i got it

$objectManager =  '\Magento\Framework\App\ObjectManager'::getInstance();
$context = $objectManager->get('Magento\Framework\App\Http\Context');
$isLoggedIn = $context->getValue(\Magento\Customer\Model\Context::CONTEXT_AUTH);

now $isLoggedIn will give us weather customer is logged in or not

if($isLoggedIn){
// code
}

and then

$customerSession = $objectManager->get('Magento\Customer\Model\SessionFactory')->create();
$user_id = $customerSession->getCustomer()->getId();

to get customer information

Answer 3

You can try this,

Methos : 1

  $objectManager = \Magento\Framework\App\ObjectManager::getInstance();  
    $customerSession = $objectManager->get('Magento\Customer\Model\Session');  
    $customerData = $customerSession->getCustomer()->getData(); 
    $customerData = $customerSession->getCustomer()->getId();// get id

//get all information of customer using $customerData

Method :2 Using inject \Magento\Customer\Model\Session $customer

  protected $customer;
    public function __construct(\Magento\Customer\Model\Session $customer,
    \Magento\Framework\View\Element\Template\Context $context)
    {
        parent::__construct($context);
        $this->customer = $customer;
    }
    public function yourMethodName()
    { 
        $customer = $this->customer;  // you can get all data using $customer
        $customerName = $customer->getName();
        $customerId = $customer->getId();
   
    }