title: how to set config or properties file for different environments in Angular?
body: <p>Angular 5.2.9 : I have to change some api keys according to different environments (pre prod, prod etc). But right now I have to change the keys in my appSettings class and build it every time before deploying on each env. Is the a way to keep the api keys inside some config or properties file so that I can keep it on each env and deploy same built code everywhere.</p>