AuthorizationCode.createToken get wrong expires_at value if I have created_at and expires_in properties.

[nickygb]

Context

• node version: 18.20.4
• module version with issue: 5.0.0
• last module version without issue:
• environment (e.g. node, browser, native): node
• any other relevant information:

What are you trying to achieve or the steps to reproduce?

I have authorization_code grant type and trying to create an AccessToken instance from what I have stored in database. The access token stored in the database has the following properties:

const tokenFromDB = {
  access_token: 'MY ACCES TOKEN',
  refresh_token: 'MY REFRESH TOKEN',
  expires_in: 43200,
  scope: 'offline_access eq1',
  token_type: 'Bearer',
  created_at: 1729699637, // October 23, 2024 4:07:17 PM
};

When I execute the createToken method I got always a token that said is not expired, despite it is.

What was the result you got?

The result I got is the following:

const accessToken = client.createToken(tokenFromDB);
console.log(accessToken);
// AccessToken {
//   token: {
//     access_token: 'MY ACCESS TOKEN',
//     refresh_token: 'MY REFRESH TOKEN',
//     expires_in: 43200,
//     scope: 'offline_access eq1',
//     token_type: 'Bearer',
//     created_at: 1729699637,
//     expires_at: 2024-10-26T10:48:59.998Z // <=== THIS SHOULD BE   2024-10-24T04:07:17.000Z
//   }
// }

What result did you expect?

const accessToken = client.createToken(tokenFromDB);
console.log(accessToken);
// AccessToken {
//   token: {
//     access_token: 'MY ACCESS TOKEN',
//     refresh_token: 'MY REFRESH TOKEN',
//     expires_in: 43200,
//     scope: 'offline_access eq1',
//     token_type: 'Bearer',
//     created_at: 1729699637,
//     expires_at:  2024-10-24T04:07:17.000Z
//   }
// }

I think the problem is here:

simple-oauth2/lib/access-token-parser.js

Lines 8 to 10 in bee1539

	function getExpirationDate(expiresIn) {
	return new Date(Date.now() + Number.parseInt(expiresIn, 10) * 1000);
	}

This function should accept also the parameter created_at. It always get the expiration date relative to now. I think the function should be something like that:

function getExpirationDate(expiresIn, createdAt) {
  return new Date( (createdAt || Date.now()) + Number.parseInt(expiresIn, 10) * 1000);
}