How to check whether the customer logged in using Events Observer

Question

I have created events.xml in app/code/Demo/Mymodule/etc/frontend:

<?xml version="1.0">
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="layout_load_before">
        <observer name="add_layout_handles" instance="Demo\Mymodule\Observer\AddHandles" />
    </event>
</config>

And AddHandles.php in app/code/Demo/Mymodule/Observer:

<?php

namespace Demo\Mymodule\Observer;

use Magento\Framework\Event\Observer;
use Magento\Framework\Event\ObserverInterface;
use Magento\Customer\Model\Session as CustomerSession;

class AddHandles implements ObserverInterface
{
    protected $customerSession;
    public function __construct(CustomerSession $customerSession)
    {
        $this->customerSession = $customerSession;
    }

    public function execute(\Magento\Framework\Event\Observer $observer)
    {
        $layout = $observer->getEvent()->getLayout();


        if (!$this->customerSession->isLoggedIn())
        {
            $layout->getUpdate()->addHandle('customer_logged_out');
        }
    }
}

On running php bin/magento setup:di:compile getting this error: arse error: syntax error, unexpected 'public' (T_STRING ), expecting function (T_FUNCTION) or const (T_CONST)

Can anyone help me?

I am using Magento 2.2.4 version.

Answer 1

Try this. You forgot to declare @var

<?php

namespace Demo\Mymodule\Observer;

use Magento\Framework\Event\Observer;
use Magento\Framework\Event\ObserverInterface;
use Magento\Customer\Model\Session as CustomerSession;

class AddHandles implements ObserverInterface
{
    /**
    * @var CustomerSession
    */
    protected $customerSession;
    /**
     * Add constructor.
     * @param CustomerSession $customerSession
     */
    public function __construct(CustomerSession $customerSession)
    {
        $this->customerSession = $customerSession;
    }

    public function execute(\Magento\Framework\Event\Observer $observer)
    {
        $layout = $observer->getEvent()->getLayout();


        if (!$this->customerSession->isLoggedIn())
        {
            $layout->getUpdate()->addHandle('customer_logged_out');
        }
    }
}

Events.XML

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../../lib/internal/Magento/Framework/Event/etc/events.xsd">
    <event name="layout_load_before">
        <observer name="add_layout_handles" instance="Demo\Mymodule\Observer\AddHandles" />
    </event>
</config>

Answer 2

Try this solution, it might be work for you.

events.xml

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../../lib/internal/Magento/Framework/Event/etc/events.xsd">
    <event name="layout_load_before">
        <observer name="add_layout_handles" instance="Demo\Mymodule\Observer\AddHandles" />
    </event>
</config>

AddHandles.php

<?php

namespace Demo\Mymodule\Observer;

use Magento\Framework\Event\Observer;
use Magento\Framework\Event\ObserverInterface;

class AddHandles implements ObserverInterface
{
    /**
     * @var \Magento\Framework\App\Http\Context
     */
    protected $_context;

    /**
     * Add constructor.
     * @param \Magento\Framework\App\Http\Context $context
     */
    public function __construct(\Magento\Framework\App\Http\Context $context)
    {
        $this->_context = $context;
    }

    public function execute(\Magento\Framework\Event\Observer $observer)
    {
        $layout = $observer->getEvent()->getLayout();


        if (!$this->_context->getValue(\Magento\Customer\Model\Context::CONTEXT_AUTH))
        {
            $layout->getUpdate()->addHandle('customer_logged_out');
        }
    }
}

This CONST (\Magento\Customer\Model\Context::CONTEXT_AUTH) use for checking the customer is logged in or not.