Cognito User Pool: How to refresh Access Token using Refresh Token

Question

I am using Cognito user pool to authenticate users in my system. A successful authentication gives an ID Token (JWT), Access Token (JWT) and a Refresh

Answer 1

Using NodeJS aws-sdk and a bit of Promise you can await authentication using Refresh Token with initiateAuth as follows:

const {CognitoIdentityServiceProvider} = require('aws-sdk');

const initiateAuth = (ClientId, REFRESH_TOKEN, DEVICE_KEY) =>
    new Promise((resolve, reject) => {
        const CISP = new CognitoIdentityServiceProvider();

        CISP.initiateAuth(
            {
                ClientId, // Cognito App Client Id
                AuthFlow: 'REFRESH_TOKEN_AUTH',
                AuthParameters: {
                    REFRESH_TOKEN,
                    DEVICE_KEY
                }
            },
            (err, data) => {
                if (err) {
                    return reject(err);
                }

                resolve(data);
            }
        );
    });

// ------ Usage ------ //

(async () => {
    const tokens = await initiateAuth('mY4pps3cR3T', '<R3FR3SHT0K3N>');

    console.log('Tokens', tokens);

    const {AuthenticationResult: {AccessToken, IdToken, ExpiresIn, TokenType}} = tokens;
})()

Keep in mind that if Device tracking is enabled you should pass a device key otherwise you can receive Invalid refresh token error.