How to access .io-config.json file values in Ionic app?

ionic-v1
1

The contents of my .io-config.json file are as follows

{"app_id":"id","api_key":"key","dev_push":bool}

I would like to find a way how to access these values in the Javascript code itself. For example:

// code
var key = config.get('api_key'); // returns the "api_key" value from .io-config.json

On this page from the legacy Ionic docs there is a similar method:

var settings = new Ionic.IO.Settings();
var app_id = settings.get('app_id');

however this does not work as I am using the new Ionic Cloud service. Is there an alternative way to achieve the same as above?