Promise not returning value on request - node.js

Question

I have been trying to get this to work, but am new to NodeJS. I suspect the issue is due to async, but am not familiar with how it works.
The idea behind this code is that it monitors a firebase database change and sends an email to the users. I am getting everything from the change snapshot, and using the values to check another table for user data. The request is not returning before the email gets sent and I am unsure why.
Edit I should specify that the email function sgMail is firing off before I get the results from the requests. I've tried putting a delay, but I am still not getting the result to return in time.
Here's my index.js
// The Cloud Functions for Firebase SDK to create Cloud Functions and setup triggers.
const functions = require('firebase-functions');
var requestify = require('requestify');
//SendGrid
const SENDGRID_API_KEY = functions.config().sendgrid.key;
const sgMail = require('#sendgrid/mail');
sgMail.setApiKey(SENDGRID_API_KEY);
// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.packingListEmail = functions.database.ref('Order/{orderID}')
.onUpdate(event => {
// Grab the current value of what was written to the Realtime Database.
const eventSnapshot = event.data;
//Here You can get value through key
var shipperInfo = eventSnapshot.child("fk_shipper_id").val();
var travelerInfo = eventSnapshot.child("fk_traveler_id").val();
//Print value of string
console.log(shipperInfo);
//Get Shipper Info
const shipperPath = 'https://shlep-me-f516e.firebaseio.com/User/'+shipperInfo+'.json';
requestify.get(shipperPath)
.then(function(response) {
// Get the response body (JSON parsed or jQuery object for XMLs)
shipperResult = response.getBody();
console.log(shipperResult.email);
return shipperResult;
});
function getTravelerData() {
return new Promise(resolve => {
requestify.get('https://shlep-me-f516e.firebaseio.com/User/' + travelerInfo + '.json')
.then(function (response) {
resolve(response.getBody())
});
});
}
var TravelD = getTravelerData();
//Send an email
const msg = {
to: 'andrew#shlepme.com',
from: 'support#shlepme.com',
subject: 'New Follower',
// text: `Hey ${toName}. You have a new follower!!! `,
// html: `<strong>Hey ${toName}. You have a new follower!!!</strong>`,
// custom templates
templateId: 'd1ccfeb9-2e2d-4979-a3ca-c53975fe486e',
substitutionWrappers: ['%', '%'],
substitutions: {
'%shipper_name%': "Test",
'traveler_name': TravelD.name
// and other custom properties here
}
};
console.log('Sending email');
console.log(TravelD);
return sgMail.send(msg)
});
Any ideas? I have been trying to figure this out.

Answer 1

It seems that you need to understand about Promises first.
When you start using promises you will need to ALWAYS use them and chain one with the other.
So I would rewrite your code like this: (not tested)
// The Cloud Functions for Firebase SDK to create Cloud Functions and setup triggers.
const functions = require("firebase-functions");
var requestify = require("requestify");
//SendGrid
const SENDGRID_API_KEY = functions.config().sendgrid.key;
const sgMail = require("#sendgrid/mail");
sgMail.setApiKey(SENDGRID_API_KEY);
// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require("firebase-admin");
admin.initializeApp(functions.config().firebase);
exports.packingListEmail = functions.database
.ref("Order/{orderID}")
.onUpdate(event => {
// Grab the current value of what was written to the Realtime Database.
const eventSnapshot = event.data;
//Here You can get value through key
var shipperInfo = eventSnapshot.child("fk_shipper_id").val();
var travelerInfo = eventSnapshot.child("fk_traveler_id").val();
//Print value of string
console.log(shipperInfo);
//Get Shipper Info
const shipperPath = "https://shlep-me-f516e.firebaseio.com/User/" + shipperInfo + ".json";
requestify.get(shipperPath)
.then(function(response) {
// Get the response body (JSON parsed or jQuery object for XMLs)
var shipperResult = response.getBody();
console.log(shipperResult.email);
return shipperResult;
})
.then(function (shipperResult) {
//Send an email
const msg = {
to: "andrew#shlepme.com",
from: "support#shlepme.com",
subject: "New Follower",
// text: `Hey ${toName}. You have a new follower!!! `,
// html: `<strong>Hey ${toName}. You have a new follower!!!</strong>`,
// custom templates
templateId: "d1ccfeb9-2e2d-4979-a3ca-c53975fe486e",
substitutionWrappers: ["%", "%"],
substitutions: {
"%shipper_name%": "Test",
traveler_name: shipperResult.name
// and other custom properties here
}
};
console.log("Sending email");
console.log(shipperResult);
return sgMail.send(msg);
});
});