How to use the Spotify Access Token outside of an Express Route - node.js

Question

I am currently learning Node.js and Express and wanted to build a simple app that queries the Spotify Web API without using an external library such as spotify-web-api-node. My code is available at https://pastebin.com/Jwe8sckJ
My "/callback" route looks like this;
app.get("/callback", function(req, res){
res.send("OK!")
var authCode = req.query.code
var options = { method: 'POST',
url: 'https://accounts.spotify.com/api/token',
headers: { 'content-type': 'application/x-www-form-urlencoded' },
form:
{ grant_type: 'authorization_code',
code: authCode,
redirect_uri: 'https://example.com/callback',
client_id: clientId,
client_secret: clientSecret } };
request(options, function (error, response, body) {
if (error) throw new Error(error);
var accessToken = JSON.parse(body).access_token;
var refreshToken = JSON.parse(body).refresh_token
console.log("Access Token: " + accessToken);
console.log("Refresh Token: " + refreshToken);
});
});
So far this is all working fine, I am able to get an Access Token and a Refresh Token. The part that I am confused about is how do I now use these tokens outside of the "/callback" route? Or maybe another way of asking would be how do I save the variables globally. If I do that, would it have any impact on new sessions to script?

Answer 1

The most common solution would be to store these tokens in a database, i.e. MongoDB or MySQL and retrieve them when needed. You'll probably want to use sessions to set the received tokens per client.
You could even save the tokens in the session, but please note that sessions are volatile.

Answer 2

If I got you right then you want to save access token for later use. You can declare global variable and can use it later.
global.spotify_access_token = '';
Declare this variable at the start of any file. Now you can use this variable to save access token in callback.like below :
spotify_access_token = JSON.parse(body).access_token;
Hope this will help you.
Thanks.