How to create product review & rating programatically in magento2

Here, I am going to explain that how to create product review & rating programatically.

Sometimes we have to create product through any external medium. For an example csv import, any other website etc.

Product review also necessary details for any product. You can create product review to use following code.

<?php

namespace Test\Module\Controller\Review;

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

class Testreview extends Action
{
    public function __construct(
        Context $context,
        \Magento\Review\Model\ReviewFactory $reviewFactory,
        \Magento\Review\Model\RatingFactory $ratingFactory,
        \Magento\Store\Model\StoreManagerInterface $storeManager
    ) {
        parent::__construct($context);
        $this->_reviewFactory = $reviewFactory;
        $this->_ratingFactory = $ratingFactory;
        $this->_storeManager = $storeManager;
    }

    public function execute()
    {
        $productId = 2047;//product id you set accordingly
        $reviewFinalData['ratings'][1] = 5;
        $reviewFinalData['ratings'][2] = 5;
        $reviewFinalData['ratings'][3] = 5;
        $reviewFinalData['nickname'] = "John Doe";
        $reviewFinalData['title'] = "Create Review Programatically";
        $reviewFinalData['detail'] = "This is nice blog for magento 2.Creating product reviews programatically.";
        $review = $this->_reviewFactory->create()->setData($reviewFinalData);
        $review->unsetData('review_id');
        $review->setEntityId($review->getEntityIdByCode(\Magento\Review\Model\Review::ENTITY_PRODUCT_CODE))
            ->setEntityPkValue($productId)
            ->setStatusId(\Magento\Review\Model\Review::STATUS_APPROVED)//By default set approved
            ->setStoreId($this->_storeManager->getStore()->getId())
            ->setStores([$this->_storeManager->getStore()->getId()])
            ->save();

        foreach ($reviewFinalData['ratings'] as $ratingId => $optionId) {
            $this->_ratingFactory->create()
                ->setRatingId($ratingId)
                ->setReviewId($review->getId())
                ->addOptionVote($optionId, $productId);
        }

        $review->aggregate();
    }
}

I have added this code in controller file. You can add this accordingly to test it.