How to get custom session value in javascript set through Magento\Framework\Session\SessionManagerInterface?

Question

Following program is used to set value of custom session variable country.

<?php

namespace Vendor\Module\Controller\Index;


use Magento\Framework\App\Action\Context;
use Magento\Framework\App\ResponseInterface;

class Country extends \Magento\Framework\App\Action\Action
{
    public function __construct(
        Context $context,
        \Magento\Framework\Session\SessionManagerInterface $sessionManager
        )
    {
        $this->session = $sessionManager;
        parent::__construct($context);
    }

    public function execute()
    {
        $countryId = $this->getRequest()->getParam('country');
        $this->session->start();
        $this->session->setCountry($countryId);
    }
}

Now, how I can get country's value in any javascript file?

Answer 1

As Amit Bera suggested in the comment section, I have added country's value to cookie and I was able to get it on other pages as given below:

Controller class to set cookie value:

namespace Vendor\Module\Controller\Index;
use Magento\Framework\App\Action\Context;
use Magento\Framework\App\ResponseInterface;
use Magento\Framework\Session\SessionManagerInterface;
use Magento\Framework\Stdlib\Cookie\CookieMetadataFactory;
use Magento\Framework\Stdlib\CookieManagerInterface;

class Country extends \Magento\Framework\App\Action\Action
{
    const COOKIE_NAME = 'country';

    /**
     * Country constructor.
     * @param Context $context
     * @param CookieManagerInterface $cookieManager
     * @param CookieMetadataFactory $cookieMetadataFactory
     */
    public function __construct(
        Context $context,
        CookieManagerInterface $cookieManager,
        CookieMetadataFactory $cookieMetadataFactory,
        SessionManagerInterface $sessionManager
        )
    {
        $this->cookieManager = $cookieManager;
        $this->cookieMetadataFactory = $cookieMetadataFactory;
        $this->sessionManager = $sessionManager;
        parent::__construct($context);
    }

    public function execute()
    {
        $countryId = $this->getRequest()->getParam('country');
        $this->set($countryId);
        return;
    }

    /**
     * @param string $value
     * @param int $duration
     * @return void
     */
    public function set($value, $duration = 86400)
    {
        $metadata = $this->cookieMetadataFactory
            ->createPublicCookieMetadata()
            //->setDuration($duration)
            ->setPath($this->sessionManager->getCookiePath())
            ->setDomain($this->sessionManager->getCookieDomain());

        $this->cookieManager->setPublicCookie(
            self::COOKIE_NAME,
            $value,
            $metadata
        );
    }
}

Get cookie value in js file as given below:

require(['jquery'], function ($) {    
var country = $.cookie('country');
console.log(country);
});

You can also open your browser's console on other pages of the site and run console.log(document.cookie); to check it's value.

If you do not need to call your controller class, you can set cookie value in your js file itself as given below:

function setCountry(country_value) {
    require(['jquery'], function ($) {    
    $.cookie('country', country_value, '/'); // set cookie value
    var country = $.cookie('country'); // get cookie value
    console.log(country);
    });
}