在没有firebase的情况下，如何在dialogflow实现中向其他服务发出http请求？

Question

I wrote a node.js fulfillment code to send my messages from Dialogflow to another services (in this code, it is postman) by simply using the http.request function.

 "use strict"; const express = require("express"); const bodyParser = require("body-parser"); const https = require('https'); const app = express(); app.use( bodyParser.urlencoded({ extended: true }) ); app.use(bodyParser.json()) app.post("/echo", function(req, res) { var speech = req.body.queryResult && req.body.queryResult.parameters && req.body.queryResult.parameters.echoText ? req.body.queryResult.parameters.echoText : "Seems like some problem. Speak again."; function mainFunction(callback){ var options = { hostname : "postman-echo.com", path : "/post", method : "POST", headers: { 'Content-Type': 'application/json' } }; var body = JSON.stringify({ message: speech }); var req = https.request(options, function(res) { var respBody = ""; console.log("Response from server started"); console.log(`Server status: ${res.statusCode}`); }); //Necessary, otherwise a socket hangup error req.end(body); req.on('response', function(res){ //console.log('STATUS: ' + res.statusCode); res.setEncoding('utf8'); res.on('data',function(chunk){ var temp = JSON.parse(chunk.toString()); //console.log('Dit is de response'); console.log(temp.data.message); var resp_message = []; if (temp.data.length > 1) { var i; for (i = 0; i < temp.data.length; i++) { var resp_message_single = temp.data[i].message; resp_message.push(resp_message_single); }; callback(resp_message) } else{ var resp_message_single = temp.data.message; resp_message.push(resp_message_single); callback(resp_message) }; }); }); }; mainFunction(function(resp_message){ if (resp_message.length != 1) { var i; speech = ""; var displayText = ""; for (i = 0; i < resp_message.length; i++) { speech = speech+resp_message[i]+'<break time="500ms"/>'; displayText = displayText+resp_message[i]+" "; }; speech = '<speak>'+speech+'</speak>'; } else{ speech ='<speak>'+resp_message+'</speak>'; displayText = resp_message[0]; }; return res.json({ fulfillmentText: speech, fulfillmentMessages:[ { text: { text: [ displayText ] } } ] }); }); }); const port = process.env.PORT || 8000; app.listen(port,()=> console.log(`Listening on port ${port}...`)); 

Now I updated my code according to this link by using the actions-on-google module, but without Firebase. However, I can't seem to use the http.request function inside the assistant.intent function in the way I used it before.

 "use strict"; const express = require("express"); const bodyParser = require("body-parser"); const https = require('https'); const {dialogflow} = require('actions-on-google'); const assistant = dialogflow(); const app = express(); app.use( bodyParser.urlencoded({ extended: true }) ); app.use(bodyParser.json()); assistant.intent('Default Welcome Intent', (conv) => { conv.ask('Welkom bij test.'); }); assistant.intent('Echo', (conv) => { var speech = conv.query var options = { hostname : "postman-echo.com", path : "/post", method : "POST", headers: { 'Content-Type': 'application/json' } };; var body = JSON.stringify({message: speech}); var req = https.request(options, function(res) { var respBody = ""; }); req.end(body); req.on('response', function(res){ res.setEncoding('utf8'); res.on('data',function(chunk){ var temp = JSON.parse(chunk.toString()); var resp_message = []; if (temp.data.length != 1) { var i; for (i = 0; i < temp.data.length; i++) { var resp_message_single = temp.data[i].message; resp_message.push(resp_message_single); }; callback(resp_message) } else{ var resp_message_single = temp.data[0].message; resp_message.push(resp_message_single); callback(resp_message) }; }); }); mainFunction(function(resp_message){ if (resp_message.length != 1) { var i; speech = ""; var displayText = ""; for (i = 0; i < resp_message.length; i++) { speech = speech+resp_message[i]+'<break time="500ms"/>'; displayText = displayText+resp_message[i]+" "; }; speech = '<speak>'+speech+'</speak>'; } else{ speech ='<speak>'+resp_message+'</speak>'; displayText = resp_message[0]; }; conv.ask(speech); }); }); app.post('/echo', assistant); const port = process.env.PORT || 8000; app.listen(port,()=> console.log(`Listening on port ${port}...`)); 

Does someone know why this happens? Is the actions-on-google module preventing that?

Answer 1

You have a few issues in your code that uses the actions-on-google library. One issue is that neither callback nor mainFunction() are defined - however, these errors hide a bigger problem that you'll run into.

When using the actions-on-google library (and when registering Intent Handlers using the dialogflow-fulfillment library, for that matter), you are expected to return a Promise if you're using a function that returns asynchronously, which is exactly what http.request does.

The easiest way is to switch to something like the request-promise-native library.

I haven't tested it, but the code for the Echo intent handler might look something like this:

assistant.intent('Echo', (conv) =>{
  const requestPromise = require('request-promise-native');
  const speech = conv.query;

  const options = {
    uri: "http://postman-echo.com/post",
    method: "POST",
    json: true,
    body: {
      message: speech
    }
  };

  return requestPromise( options )
    .then( body => {
      let speech = "I didn't hear anything.";
      let text   = "I didn't hear anything.";
      if (body.data && body.data.length > 0){
        speech = body.data[0].message;
        text   = body.data[0].message;
        for (let co=1; co<body.data.length; co++){
          speech += `<break time="500ms"/>${body.data[co].message}`;
          text   += ' '+body.data[co].message;
        }
      }
      speech = `<speak>${speech}</speak>`;
      return conv.ask( new SimpleResponse({
        speech: speech,
        text:   text
      }));
    });

});