GET https://dribbble.com/oauth/authorize

window.location.href = https://dribbble.com/oauth/authorize?client_id=clientidhere&redirect_uri=http://localhost:4200/signup?step=three&state=230948lksdjf02384ldskf

exports.oAuthUserLink = functions.https.onRequest((req, res) => {
  cors(req, res, () => {
    return getAuthToken(req, res, admin, config, otherConfig);
  });
});

getAuthToken = function (req, res, admin, fbConfig, config) {
  const rp = require('request-promise');

  const oAuthUrl = 'https://dribbble.com/oauth/token?';
  const code = '&code=' + req.query.code;
  let state = '&state=' + req.query.state;
  const clientId = '?client_id=' + config.dribbble.client_id;
  const secret = '&client_secret=' + config.dribbble.client_secret;

  const options = {
    method: 'POST',
    uri: oAuthUrl + clientId + secret + code + state,
    headers: {
      'Accept': 'application/json',
      'Content-Type': 'application/x-www-form-urlencoded'
    }
  };

  rp(options)
  .then(body => {
    const bodyObj = JSON.parse(body);
    console.log('bodyObj', bodyObj)
  });

}

{
    "error": "invalid_grant",
    "error_description": "The provided authorization grant is invalid, expired, revoked, does not match the redirection URI used in the authorization request, or was issued to another client."
}

exports.redirect = function (req, res, admin) {
  const config = functions.config();
  const rp = require('request-promise');

  const state = req.query.state;
  const userId= req.query.userId;
  const redirectUrl = `https://us-central1-my-test-app.cloudfunctions.net/oAuthUserLink`;
  //here I've changed the redirectUrl from localhost to the endpoint to my function above
  const clientId = config.dribbble.client_id;

    const getToken = {
      uri: `https://dribbble.com/oauth/authorize`,
      qs: {
        client_id: clientId,
        state: state,
        redirect_uri: redirectUrl
      },
      headers: { 'User-Agent': 'Needly Workcoin Market'}
    };

  rp(getToken).then(response => {
    res.send(response); //this response is a 302 redirect to their login page
  });
}