Sending dynamic data in response using agent.add() - dialogflow-es

Question

My requirement is to send dynamic data with response using Dialogflow’s Nodejs fulfillment library beta.
My query is to know the possibility of sending dynamic data with response which we got that from external api ? There are cases where we need to send real time data to dialogflow agent ( in turn to client) by calling a API . I tried below code to implement this but its not working , here " value" is the data that we are getting from api response and the same has been parsed / navigated to extract json value.
agent.add(stock price is + JSON.parse(value).IRXML.StockQuotes.Stock_Quote[0].Trade)
Prior above code execution , i'm making a synchronous external API call using promotion so that the result is replaced in the agent.add section.
At present, i'm not able to execute agent.add function inside promotion then function. Please do assist me to implement this or let me know is there any alternative approaches to do this.
Im making a external api call to fetch data so that i can sent same result back to agent. I could able to make call but i'm really not sure how to pass this received data to agent. As you can see in the below code , im calling externalCall() to make api call and this function is called from SpineDay(). The result returned from externalCall() is replaced in SpineDay(), still the result is not passed to agent using agent.add(). Any instruction agent.add() with in "externalCall(req,res).then" is not working.
function SpineDay(agent){
externalCall(req,res).then((output,agent) => {
//res.json({ 'fulfillmentText': JSON.parse(output).IRXML.StockQuotes.Stock_Quote[0].Trade });
agent.add(new Card({
title: output,
imageUrl: 'https://dialogflow.com/images/api_home_laptop.svg',
text: `This is the body text of a card. You can even use line\n breaks and emoji!`,
buttonText: 'Se rendre sur XXX',
buttonUrl: 'https://XXX/'
})
);
agent.add(new Suggestion(`Quelles sont les dernière sorties à la demande?`));
agent.add(new Suggestion(`Quel est le programme de ce soir?`));
}).catch(() => {
res.json({ 'fulfillmentText': `Error calling the weather API!` });
});
/*agent.add("Quelles sont les dernière sorties à la demande?");
agent.add("`Quel est le programme de ce soir?");*/
}
var externalCall = function(mainreq, mainres) {
return new Promise(function(resolve, reject){
// Create the path for the HTTP request to get the weather
var jsonObject = JSON.stringify(mainreq.body);
const agent = new WebhookClient({request: req, response: res});
console.log('In side post code' + Buffer.byteLength(jsonObject, 'utf8'))
// An object of options to indicate where to post to
var options = {
port: '443',
uri: 'https://xxxx.xxx.xxx//ticker/quote/stock?compid=22323&reqtype=quotes',
method: 'POST',
headers: {
'Content-Length' : Buffer.byteLength(jsonObject, 'utf8'),
'X-MDT-API-KEY': 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'
}
};
// Make the HTTP request to get the weather
request(options, function(err, res, body) {
if (!err && res.statusCode == '200'){
// After all the data has been received parse the JSON for desired
// data
let response = JSON.parse(body).IRXML.StockQuotes.Stock_Quote[0].Trade;
// Create response
let output = "xxxx stock price is " +response;
// Resolve the promise with the output text
console.log(body);
resolve(output,agent);
}else{
console.log(`Error calling the weather API: ${error}`)
reject("Error calling the weather API");
}
});
});
}

Answer 1

The problem is that your SpineDay function is making an asyc call, but not returning a Promise. Although externalCall is (correctly) using Promises, SpineDay isn't. The library assumes that, if you make an async call, you will return a Promise that will be fullfilled when the response is ready to send.
Fortunately, you can do that with a few additional lines in your function that returns a promise overall and returns a Promise as part of the promise chain.
function SpineDay(agent){
return externalCall(req,res)
.then((output,agent) => {
agent.add(new Card({
title: output,
imageUrl: 'https://dialogflow.com/images/api_home_laptop.svg',
text: `This is the body text of a card. You can even use line\n breaks and emoji!`,
buttonText: 'Se rendre sur XXX',
buttonUrl: 'https://XXX/'
})
);
agent.add(new Suggestion(`Quelles sont les dernière sorties à la demande?`));
agent.add(new Suggestion(`Quel est le programme de ce soir?`));
return Promise.resolve();
}).catch(() => {
res.json({ 'fulfillmentText': `Error calling the weather API!` });
return Promise.resolve();
});
}
So first, you need to return the result of the .then().catch() chain, which will be a Promise. Then, inside the chain you also need to return the result, which is best done as a Promise.