Stop api.ai from chatting

stop_chatting.js

const admin = require('firebase-admin');
const auth = require('basic-auth')
const functions = require('firebase-functions');

admin.initializeApp(functions.config().firebase);

exports.webhook = functions.https.onRequest((req, res) => {
  // Check if api.ai provides a correct user/pass
  const credentials = auth(req);
  if (!credentials || credentials.name != 'username' || credentials.pass != 'password') {
    console.log('Incorrect authentication header');
    res.set('WWW-Authenticate', 'Basic realm=Authorization Required');
    return res.send(401);
  }

  const fbMessageInfo = req.body.originalRequest;
  if (!fbMessageInfo || fbMessageInfo.source !== 'facebook') {
    console.log('No fb message info attached with the request.\n' +
    'Check whether your message are actually coming from FB?');
    return res.send(400);
  }

  const userId = fbMessageInfo.data.sender.id;
  const pageId = fbMessageInfo.data.recipient.id;
  const timestamp = fbMessageInfo.data.timestamp;
  const routingOnDb = `/${pageId}/${userId}`;
  admin.database().ref(routingOnDb).once('value').then((snapshot) => {
    const userDataOnDb = snapshot.val();
    if (userDataOnDb) {
      // Clear a user record on DB if it is already more than the desired wait time.
      const dataOnDatabase = snapshot.val();
      const endTimestamp = dataOnDatabase.endTimestamp;
      const userWaitTime = dataOnDatabase.waitTime;
      if (timestamp > endTimestamp) {
        console.log('Wait time is over. Release a user.');
        return admin.database().ref(routingOnDb).set(null).then(snapshot => {
          return res.send(400);
        });
      }
      return res.json({
        speech: ' ',
        displayText: ' ',
        source: 'firebase-functions',
      });
    } else {
      const action = req.body.result.action;
      console.log(`Received action ${action}`);
      if (action !== 'action.wait') {
        return res.send(400);
      }
      // Put user to a wait state.
      // Also, record the end timestamp when we want to release the user.
      const waitTime = req.body.result.parameters.waitTime;
      return admin.database().ref(routingOnDb).set({
        userId,
        pageId,
        endTimestamp: timestamp + waitTime * 1000,
        waitTime,
      }).then(snapshot => {
        console.log('1st time - push a user record to DB');
        const text = `Stop bot for ${waitTime} seconds`;
        return res.json({
          speech: text,
          displayText: text,
          source: 'firebase-functions',
        });
      });
    }
  });
});