如何为开发环境模拟https环境/ SSL证书？

I have a PHP application which runs on production like this :

<?php

    /*
    Do some work here
    */

    /* if https environment, redirect to secure next url */
    if(empty(isset["HTTPS"]) == true )  /* FIRST DEPENDECY */
    {
      header("location : https://mynext_prod_url?parameters"); /*SECOND DEPENDENCY */
    }
    else
    {
       header("location : http://mynext_prod_url?parameters");
    }
?>

This works absolutely fine in production where a SSL certificate is installed. To simulate the same scenarios in development, I can overcome first dependency, but how shall I overcome the second ?

/* Development example with workarounds */

  <?php

        /*
        Do some work here
        */
        $_SERVER['HTTPS'] = "TRUE" ;         /* fake HTTPS  */   

        if(isset($_SERVER["HTTPS"]) == true )  /* FIRST DEPENDECY SOLVED */
        {
          /* BUT THIS URL DOES NOT WORK AS IT ONLY EXISTS ON HTTP */
          header("location : https://mynext_dev_url?parameters"); 
        }
        else
        {
           header("location : http://mynext_dev_url?parameters");
        }
    ?>

How can I install a temporary certificate for development purpose ? Or somehow fake the environment .