Add customer session object and use in templates

Question

I want to omit all object manger-like methods.

Is there any smart way to add customer session object (for example check logged/non-logged user to display different content) into template? Of course it can be done via DI in each block we need but it needs a lot of overriding which is not a good solution.

Maybe it can be done by injecting it in di.xml as argument to desired blocks?

Or just adding it to context block somehow?

Answer 1

Maybe it can be done by injecting it in di.xml as argument to desired blocks?

Not in di.xml, because this is all about the constructor parameters and since you don't want to create new block classes, this option is dropped.

But you can add arguments via layout XML, like this:

<referenceBlock name="the-block-name">
  <arguments>
    <argument name="customer_session" xsi:type="object">Magento\Customer\Model\Session</argument>
  </arguments>
</referenceBlock>

Now you can reference the session in your template with

$block->getCustomerSession()

Documentation: http://devdocs.magento.com/guides/v2.1/frontend-dev-guide/layouts/xml-instructions.html

---

However, just because this is possible, it does not mean that it is the best solution. In my opinion, this is the same kind of dependency than using the object manager in the template, it's just hidden well, which makes it even worse.

From the code there is no evidence of the dependency anymore, and the template only works if this argument is passed via layout XML.

A new block class is the better option. But you should not override the original block via DI preferences, but rather change the block type together with the template via layout XML. Now the new template is coupled with the new block type and its dependency to the session is explicit in code.

Answer 2

In Magento 1, you had the option to handle things with the customer_logged_in or customer_logged_out handle. Those handles are not available anymore in Magento 2. Instead of using a Session in you templates, you could add the missing handles by an Observer and add your changes via layout.xml.

Check out here: MAGENTO 2 : GET CUSTOMER_LOGGED_IN AND CUSTOMER_LOGGED_OUT LAYOUT HANDLES

In case the first way doesn't solve your problem, you could inject your session into the object you need by constructer injection. Navigate to you block, and add the session object to your constructer:

/**
 * YOURBLOCK constructor.
 *
 * @param Template\Context                    $context
 * @param \Magento\Backend\Model\Auth\Session $authSession
 * @param array                               $data
 */
public function __construct(
    Template\Context $context, 
    \Magento\Backend\Model\Auth\Session $authSession, 
    array $data = []
) {
    parent::__construct($context, $data);
    $this->authSession = $authSession;
}

Answer 3

You can create a helper for that and using it on your codes.

<?php $helper = $this->helper('Vendor\Checklog\Helper\Data'); ?>

call helper like this.

Helper codes to check logged in -

<?php
namespace Vendor\Checklog\Helper;

use Magento\Customer\Model\Context;

class Data extends \Magento\Framework\App\Helper\AbstractHelper
{
    /**
     * @var \Magento\Framework\App\Http\Context
     */
    protected $_httpContext;

    /**
     * @param \Magento\Framework\App\Http\Context $httpContext
     * 
     */
    public function __construct(
        \Magento\Framework\App\Http\Context $httpContext
    ) {
        $this->_httpContext = $httpContext;
    }

    public function isLoggedIn()
    {
        if($this->_httpContext->getValue(Context::CONTEXT_AUTH)) {
            return true;
        }
        return false;
    }
}