Recently i wrote a library to get values from environment variables and parse to the PHP data types. This library can be used to parse environment variables to PHP data types (like the casting to integer, float, null, boolean), parse the complex data structures like a JSON string and more with the contribution of the commnunity.
The library is available here: https://github.com/jpcercal/environment
Setup your environment variables, after if you are using a web server (restart your Apache Server or PHP Built-in Server or Nginx) else if you are running a cli application close and reopen the terminal program to load your new environment variables to operational system.
And to get the values from environment variable with PHP use my library (independently of the environment CLI, Apache, Nginx, PHP Built-in Server and more) to do it:
<?php
// ...
require "vendor/autoload.php";
// ...
var_dump(Cekurte\Environment\Environment::get("YOUR_ENV_VARIABLE_NAME"));
Enjoy it.