dialogflow-nodejs-webhook

There are different ways to call the api.ai or dialogflow . But for this demo , we will be using one of the method to define a custom webhook to call the dialogflow with a response from our Express Server .

Here's the documentation :

Express

🔥 Express 🚀 Serveo

First create a Express server on index.js

const express= require('express');
const app =  express();
require('./routes')(app);

const PORT = process.env.PORT  || 3000;
const serveoPORT  = "<<Put_your_serveo_url>>";
app.listen(PORT  ,() =>  {
    console.log(`The ngrok server is  ${serveoPORT} \n express server is listening on ${PORT}`)
})

Then create a single POST route for the webhook on routes.js and include it in index.js (look above 🤘 )

Use **node_fetch** for making async request to third party library to get some data

const fetch = require('node-fetch');
module.exports = (app) => {

    app.post('/moviebot/get-movie-details', (req, res) => {
                      fetch('<<your_external_url>.')
                        .then( data => {
                          res.json({
                              "fulfillmentText": data,
                              "source": "get-top-rated-movies"
                          });
                       }).catch(error => console.log(error.message));
                
        });
}

Here the response key I am sending is predefined by the dialogflow fulfillment API

  res.json({
          "fulfillmentText": data,
          "source": "get-top-rated-movies"
       });

It does have other key value pair too for sending Rich text messages into the Dialgflow api Here's the Different type of Response you can send through your res.json() call :

🚀 DialogFlow Docs Look upon the v2 API.

Next step, is to install serveo:
🎉 Serveo

Serveo

Serveo is an SSH server just for remote port forwarding. When a user connects to Serveo, they get a public URL that they can use to connect to their localhost server , in this case it's our local Express Server , to tunnel all the public request to Severo URL from dialogflow fulfillment endpoint. We will mention the Public URL in Dialogflow as our endpoint flows control to ---> Express server running.

Run:

ssh -R 80:localhost:3000 serveo.net

That's it . You have completely set up your nodejs webhook . Good luck Exploring , Thanks.