Rakesh Jesadiya

Magento 2 Get Configurable product id from Child id of configurable. When you have Child id of the P product is available you can simply get the parent config product id.

Create simple block to get parent product id,

<?php
namespace Rbj\Product\Block;

class Product extends \Magento\Framework\View\Element\Template
{
	public function __construct(
        \Magento\Framework\View\Element\Template\Context $context,
        \Magento\ConfigurableProduct\Model\Product\Type\Configurable $configurable,
        array $data = []
    ) {
        $this->configurable = $configurable;
        parent::__construct($context, $data);
    }

    /**
     * @param int $childId
     * @return int
     */
    public function getParentProductId($childProductId)
    {
            $parentConfigObject = $this->configurable->getParentIdsByChild($childProductId);
	    if($parentConfigObject) {
		return $parentConfigObject[0];
	    }
	    return false;
    }
}

now call the function in template file to get Parent Id,

$childId = 10;
echo $block->getParentProductId($childId);