Slack OAuth v2

oauth.js

const installUrl = `https://slack.com/oauth/v2/authorize?\
client_id=${process.env.SLACK_CLIENT_ID}&scope=${process.env.SLACK_SCOPES}`;


module.exports.save = async function (data) {
  await saveDoc(data);
}

var saveDoc = async function(data) {
  //
}

module.exports.install = (app, slack) => {
  app.route('/oauth')
    .get((request, response) => {
      console.log('Request for /oauth');
      const payload = request.query;

      if (!payload.code) {
        return response.redirect(302, installUrl);
      }

      return slack.oauth.v2
        .access({
          client_id: process.env.SLACK_CLIENT_ID,
          client_secret: process.env.SLACK_CLIENT_SECRET,
          code: payload.code,
          state: payload.state
        })
        .then(data => {
          console.log('Saving auth data for:', data.team.id);
          const save = this.save({
            //
          });

          const test = slack.auth.test({ token: data.access_token });

          Promise.all([test]).then(results => {
            response.redirect(302, results[0].url);
          });
        })
        .catch(error => {
          console.log('Error with /oauth:', error)
          response.status(500).send(error);
        })
    });

  app.route('/install')
    .get((request, response) => {
      console.log('Request for /install');
      response.redirect(302, installUrl);
    })
}

module.exports.auth = ({ teamId }) => {
  console.log('Request for .auth for:', teamId);
  //

  return Promise.resolve(getDoc);
}