How to trigger an observer programatically with it's required data from a custom controller file in Magento 2?

Question

I have create event controller_action_predispatch_checkout_cart_add as given below:

Vendor/Module/etc/frontend/events.xml

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="controller_action_predispatch_checkout_cart_add">
        <observer name="bialcheckout_before_product_add_to_cart" instance="Vendor\Module\Observer\ProductBeforeAddToCart" />
    </event>
</config>

Vendor/Module/Observer/ProductBeforeAddToCart.php

<?php
namespace Vendor\Module\Observer;
use Magento\Framework\Event\Observer;
use Magento\Framework\Event\ObserverInterface;

class ProductBeforeAddToCart implements ObserverInterface {
 public function __construct(
// dependencies
){
....
}
public function execute(Observer $observer)
{ 
    $productId = $observer->getRequest()->getParam('product');
    $superAttributes = $observer->getRequest()->getParam('super_attribute');
    // Rest of the code
}
}

Above code works fine if I add product from product details page. Now in one of my custom module, I am adding product to cart programatically. After product is added to cart programatically, above method is not executed automatically. From my custom module I want to call my code written in the above observer with product data. How I can do that?

I mean, How to trigger a observer programatically with it's required data from a custom controller file ?

Answer 1

You can try to add this below code in your controller :

/**
 * Core event manager proxy
 *
 * @var \Magento\Framework\Event\ManagerInterface
 */
protected $_eventManager;

public function __construct(
    .....
    \Magento\Framework\Event\ManagerInterface $eventManager,
    .....
) {
    .....
    $this->_eventManager = $eventManager;
    .....
}

public function execute()
{
    //your code
    //you can pass param value and set condition here as per your requirement. 
    $this->_eventManager->dispatch(
                'controller_action_predispatch_checkout_cart_add',
                ['category' => $category, 'request' => $this->getRequest()]
            );
}

Answer 2

In addition to what Rohan as shared, You can prepare your parameters as given below:

<?php
namespace Vendor\Module\Controller\Index;
class AddToCart extends \Magento\Framework\App\Action\Action {
   public function __construct(
    \Magento\Framework\App\Action\Context $context,
    \Magento\Checkout\Model\Cart $cart,
    \Magento\Catalog\Api\ProductRepositoryInterface $productRepository,
    \Magento\Eav\Model\ResourceModel\Entity\Attribute $eavAttribute,
    \Magento\Framework\Event\ManagerInterface $eventManager,
    \Magento\Framework\App\RequestInterface $request,
     \Magento\Framework\Controller\Result\JsonFactory $jsonFactory
)
{
    parent::__construct($context);
    $this->_cart = $cart;
    $this->productRepository = $productRepository;
    $this->eavAttribute = $eavAttribute;
    $this->eventManager = $eventManager;
    $this->jsonFactory = $jsonFactory;
    $this->request = $request;
}

    public function execute() {

        $sizeAttributeId = $this->eavAttribute->getIdByCode('catalog_product', 'size');
        $colorAttributeId = $this->eavAttribute->getIdByCode('catalog_product', 'color');
        $parentProductId = $this->getRequest()->getParam('parentId');
        $colorOptionId = $this->getRequest()->getParam('colorOptionId');
        $sizeOptionId = $this->getRequest()->getParam('sizeOptionId');
        $qty = $this->getRequest()->getParam('qty');

        $result = $this->jsonFactory->create();

        $options = array(
                        $colorAttributeId => $colorOptionId,
                        $sizeAttributeId => $sizeOptionId
                    );

        $params = array(
            'product' => $parentProductId,
            'super_attribute' => $options,
            'qty' => $qty
        );

        $this->request->setPostValue('product', $parentProductId); // prepare your parameters
        $this->request->setPostValue('super_attribute', $options);
        $this->request->setPostValue('qty', $qty);

        $product = $this->productRepository->getById($parentProductId);
        $this->_cart->addProduct($product,$params);
        $this->eventManager->dispatch(
        'controller_action_predispatch_checkout_cart_add',
                ['product' => $product, 'request' => $this->request]
                );
        $this->_cart->save();
        return $result->setData(['status' => 200]);
    }
}