How to call an API from Dialog Flow using get method?

Question

My question is about the the use of API in Webhook. I used this code for calling an external API from my localhost using ngrok. I have tried Using 3rd party API within Dialogflow Fulfillment as well, but still not working for my case. This is my code -

'use strict';

var https = require ('https');

const functions = require('firebase-functions');

const {WebhookClient} = require('dialogflow-fulfillment');

const {Card, Suggestion} = require('dialogflow-fulfillment');

process.env.DEBUG = 'dialogflow:debug';

exports.dialogflowFirebaseFulfillment = functions.https.onRequest((request, response) => {
const agent = new WebhookClient({ request, response });
console.log('Dialogflow Request headers: ' + 
JSON.stringify(request.headers));
console.log('Dialogflow Request body: ' + JSON.stringify(request.body));

function welcome(agent) {
  agent.add(`Welcome to my agent!`);
}

function fallback(agent) {
 agent.add(`I didn't understand`);
 agent.add(`I'm sorry, can you try again?`);
}

function get_products(agent){
  var url = 'https://705861b5.ngrok.io/products';
  https.get(url, function(res){
    var body = '';
    res.on('data', function(chunk){
      body += chunk;
    });
    res.on('end', function(){
     var respose_jquery = JSON.parse(body);
     agent.add("Got a response: ", respose_jquery.product_name);
    });
  }).on('error', function(e){
    agent.add("Got an error: ", e);
  });   
}

let intentMap = new Map();
intentMap.set('Default Welcome Intent', welcome);
intentMap.set('Default Fallback Intent', fallback);
intentMap.set('show_products', get_products);
agent.handleRequest(intentMap);

});

How is that request related to dialogflow?. What Dialogflow API are you trying to call? — Marcos Casagrande, Mar 09 '19 at 17:00
I am building a chat-bot in Dialog flow. This is the function, I wrote in fulfilment. — imnikhilanand, Mar 09 '19 at 17:04
You're using `inline editor` via Cloud Functions for Firebase, or the webhook? — Marcos Casagrande, Mar 09 '19 at 17:14
Then show your whole code, what's agent, show you'r express setup, everything. — Marcos Casagrande, Mar 09 '19 at 17:20
Default Output. "webhookStatus": { "message": "Webhook execution successful" } — imnikhilanand, Mar 09 '19 at 17:50
shouldn't you add 'return' before your API call (e.g. return https.get(...)) to wait for a result before resolving? — davidverweij, Mar 09 '19 at 17:52
On doing that I get this error - "message": "Webhook call failed. Error: 500 Internal Server Error" — imnikhilanand, Mar 09 '19 at 18:01
Are there any additional error logs? do add 'return' before agent.add() in your https call - so that it return something. — davidverweij, Mar 09 '19 at 18:06
@davidverweij, The problem is still not fixed. I realised that I am using free plan. To access Non-google server one have get Blaze-Plan. https://stackoverflow.com/questions/43415759/use-firebase-cloud-function-to-send-post-request-to-non-google-server — imnikhilanand, Mar 10 '19 at 15:19

score 1 · Answer 1 · answered Mar 10 '19 at 04:02

The issue is that the dialogflow-fulfillment library assumes that you will return a Promise if you do any async functions, such as the https calls in your get_products() function.

Although you can wrap your code in something that returns a Promise, the easiest way to do this is to use something like the request-promise-native library. It might look something like this (untested):

const rp = require('request-promise-native');

function get_products(agent){
  var url = 'https://705861b5.ngrok.io/products';
  var options = {
    uri: url,
    json: true
  };
  return rp.get( options )
    .then( body => {
      agent.add("Got a response: "+body.product_name);
    })
    .error( err => {
      agent.add("Got an error: " + e);
    });
}

I get error using axis, should I using request-promise-native ?? the error using axis : getaddrinfo EAI_AGAIN — poppop, Jul 09 '19 at 04:16
You can try, but this sounds like an unrelated problem. I suggest you [create a new question](https://stackoverflow.com/questions/ask) and provide as many details as you can (code, what environment you're running in, etc). — Prisoner, Jul 09 '19 at 15:32

How to call an API from Dialog Flow using get method?

1 Answers1