ローカル環境の時だけ自己署名証明書のサイトへの file_get_contents を通す

fileGetContents.php

<?php

$environment = 'local'; // prod, stg, local, etc...

function fileGetContents(String $url)
{
    global $environment;
    if ($environment == 'local') {
        $options = array(
            'ssl' => array(
                'verify_peer' => false,
                'verify_peer_name' => false,
            )
        );

        return file_get_contents($url, false, stream_context_create($options));
    }

    return file_get_contents($url);
}

echo fileGetContents("https://google.co.jp");