title: How do I read a configuration parameter or file in Angular 4
body: <p>I need to read - in an Angular Service Class(TypeScript) - a configuration file with a base URL of a web service I consume data from. </p>
  
  <p>It is just an Ajax call with a HttpClient, but I am new to angular.</p>
  
  <p>I serve my app from a <strong>Node.js</strong> server.</p>
  
  <p>This baseUrl changes and that's why it needs to be configured. In fact, I also wanted to check if it is possible to define the base Url as a start up parameter.</p>