title: Make get request to third party API with api key using express.router();
body: <p>I am building a react app, and in it I am retrieving data from a third party site which requires me to send the API key in the header using 'X-Auth-Token'.</p>
  
  <p>Currently I am making this request using fetch() api from the clientside js files.
  I understand this is bad practice and I should hide my api key, so this is what I am trying to do but am finding it hard to understand how all the components fit together in this puzzle...</p>
  
  <p>I have followed a tutorial and now have a create-react-app project listening locally on port 3000, and an express server (using express.router()) listening locally on port 9000.</p>
  
  <p>I want to make the api request to the third party from the express server, and then send that to the front end.</p>
  
  <ol>
  <li>using express.router(), how would i make a request to a third party that includes my api key, and then send that on to the front end?</li>
  <li>when i eventually host this project (i am hosting on heroku), instead of the front end making a fetch request to port9000 to retrieve the data from the express server request, what url should it be listening to? - I think i lack understanding when it comes to this part.</li>
  </ol>