How to create API Endpoint in Magento2?

Question

I want to create API route which can list/return products data in JSON or XML format.

By creating this endpoint I will be able to fetch the all the products from Magento. Then I will access it on my website. What I tried is below:

public function getMagentoProducts()
{
    $productArr = array('' => 'Select Product');
    try {
        $proxy = new SoapClient('https://shop.mysite.com/soap?wsdl');
        $sessionId = $proxy->login(sfConfig::get('app_mgt_api_user'), sfConfig::get('app_mgt_api_key'));
        try {
            $mgtProducts = $proxy->call($sessionId, 'product.list');
            if (count($mgtProducts) > 0) {
                foreach ($mgtProducts as $product) {
                    $productArr[$product['product_id']] = $product['name'];
                }
            }
            return $productArr;
        } catch (Exception $e) {
            $this->forward404($e->getMessage());
        }
    } catch (Exception $e) {
        $this->forward404($e->getMessage());
    }
}

But by running the above code it throws the below error:

SOAP-ERROR: Parsing WSDL: Couldn't load from 'https://shop.mysite.com/soap?wsdl' : failed to load external entity "https://shop.mysite.com/soap?wsdl"

Am I doing something wrong here?

Is there any easy way to fetch products list from Magento2 on my website?