Getting undefined error when printing a variable - node.js

Question

I am retrieving data from the firestore to get the data. I store the data into a variable. I need to use that variable in another part of the code. when I use that it shows me an undefined code. I retrieved the user details and sending the notification . In datapayload I need to pass the retrieved field . But it shows an error undefined
cloud functions
const functions = require('firebase-functions');
const Firestore = require('#google-cloud/firestore');
const firestore = new Firestore();
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
const db = admin.firestore();
exports.splitting = functions.firestore
.document('deyaPayUsers/{authid}/Split/{authid1}/SentInvitations/{autoid}')// Here the path is is triggereing
.onWrite(event =>{
var id = event.params.authid;//here we get the authid of the user who triggeres.
var dbref = db.collection('deyaPayUsers').doc(id);
var sendername ;
var getDoc = dbref.get()
.then(doc =>{
if(!doc.exists){
console.log("No Such Document");
}else{
console.log('Document data of the firstname', doc.data().FirstName);
sendername = doc.data().FirstName;
}
console.log("sent"+sendername);
})
.catch(err => {
console.log("error getting document",err);
});
console.log(id);
var id1 = event.params.authid1;
var splitid = event.params.autoid;
console.log("laha"+sendername);
var document = event.data.data();
var phoneNumber = [];
//In loop
for(var k in document){ // this line says about looping the document to get the phonenumber field in all the invites
phoneNumber.push(document[k].PhoneNumber);// All the phonenumbers are stored in the phoneNumber array.
}
console.log("The json data is " +phoneNumber);
var ph1 = document.Invite1.PhoneNumber;//It gets the single user phoneumber in Invite1
var amount = document.Invite1.Amount;//It gets the amount of the single user in invite1 in integer
var a = amount.toString();// It is used to convert the Integer amount into String
console.log(a);
console.log(document);
console.log(ph1);
var deyaPay = db.collection("deyaPayUsers");// This path is user profile path to query with phonenumber
for(var k in document){ // here It is the loop in a document to get the phonenumber
var p = document[k].PhoneNumber;// here we get the phonenumber for every loop in invite and stored in p variable
var am = document[k].Amount;// we get the amount of that invite
var ams = am.toString();// converting integer amount into string
console.log("AMount of the user"+ams);
let phQuery = deyaPay.where('PhoneNumber','==',p)// This line says that checking the user proile PhoneNumber field and the document phonenumber which is stored in p variable.
.get()
.then(snapshot => {
snapshot.forEach(doc=>{ // It loops all the documnets whether the PhoneNumbers are matching with user profiles phonenumber
console.log(doc.id, " => ", doc.data());// If matches it prints the doc id and the user data
var userData = doc.data();//Here we get the doc data of that matched phonenumber
var userId = doc.id;// here it we get the id of the Matched profile
var FirstName = userData.FirstName;
console.log(FirstName);
var LastName = userData.LastName;
console.log(FirstName);
var FullName = FirstName + LastName;
console.log(FullName);
var Token = userData.FCMToken; // we need to take that fcm token to send the notification
console.log(userId);
console.log("FCM Token for that phoneNumber" + Token);
console.log(userData.PhoneNumber);
console.log(ph1 + "Exist In DB");
var msg = FirstName + " "+ "requested you to pay $" +ams;
console.log("total notification is" +msg);
let payload = { //This is for sending notification message
notification: {
title: "Message",
body: msg,
sound: "default",
},
'data':{// these is the data it calls in the messagereceived method
'Name':sendername,
'Amount':ams
}
};
console.log(payload);
return admin.messaging().sendToDevice(Token, payload).then((response)=> { // This method is used for returning the notification to a specific device
console.log(Token);
console.info("Successfully sent notification")
}).catch(function(error) {
console.warn("Error sending notification " , error)
});
});
}) .catch(err => {
console.log('Error getting documents', err);
});
}
});

Answer 1

try this, Problem is whenever you perform any async operation in node.js, it does not wait for it to complete execute next line.
const functions = require('firebase-functions');
const Firestore = require('#google-cloud/firestore');
const firestore = new Firestore();
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
const db = admin.firestore();
exports.splitting = functions.firestore
.document('deyaPayUsers/{authid}/Split/{authid1}/SentInvitations/{autoid}') // Here the path is is triggereing
.onWrite(async (event) => {
try {
const responses = [];
var id = event.params.authid; //here we get the authid of the user who triggeres.
var dbref = db.collection('deyaPayUsers').doc(id);
var sendername;
var doc = await dbref.get();
if (!doc.exists) {
console.log("No Such Document");
} else {
console.log('Document data of the firstname', doc.data().FirstName);
sendername = doc.data().FirstName;
}
console.log(id);
var id1 = event.params.authid1;
var splitid = event.params.autoid;
console.log("laha" + sendername);
var document = event.data.data();
var phoneNumber = [];
//In loop
for (var k in document) { // this line says about looping the document to get the phonenumber field in all the invites
phoneNumber.push(document[k].PhoneNumber); // All the phonenumbers are stored in the phoneNumber array.
}
console.log("The json data is " + phoneNumber);
var ph1 = document.Invite1.PhoneNumber; //It gets the single user phoneumber in Invite1
var amount = document.Invite1.Amount; //It gets the amount of the single user in invite1 in integer
var a = amount.toString(); // It is used to convert the Integer amount into String
console.log(a);
console.log(document);
console.log(ph1);
var deyaPay = db.collection("deyaPayUsers"); // This path is user profile path to query with phonenumber
for (var k in document) { // here It is the loop in a document to get the phonenumber
var p = document[k].PhoneNumber; // here we get the phonenumber for every loop in invite and stored in p variable
var am = document[k].Amount; // we get the amount of that invite
var ams = am.toString(); // converting integer amount into string
console.log("AMount of the user" + ams);
let snapshot = await deyaPay.where('PhoneNumber', '==', p) // This line says that checking the user proile PhoneNumber field and the document phonenumber which is stored in p variable.
.get();
snapshot.forEach(doc => { // It loops all the documnets whether the PhoneNumbers are matching with user profiles phonenumber
console.log(doc.id, " => ", doc.data()); // If matches it prints the doc id and the user data
var userData = doc.data(); //Here we get the doc data of that matched phonenumber
var userId = doc.id; // here it we get the id of the Matched profile
var FirstName = userData.FirstName;
console.log(FirstName);
var LastName = userData.LastName;
console.log(FirstName);
var FullName = FirstName + LastName;
console.log(FullName);
var Token = userData.FCMToken; // we need to take that fcm token to send the notification
console.log(userId);
console.log("FCM Token for that phoneNumber" + Token);
console.log(userData.PhoneNumber);
console.log(ph1 + "Exist In DB");
var msg = FirstName + " " + "requested you to pay $" + ams;
console.log("total notification is" + msg);
let payload = { //This is for sending notification message
notification: {
title: "Message",
body: msg,
sound: "default",
},
'data': { // these is the data it calls in the messagereceived method
'Name': sendername,
'Amount': ams
}
};
console.log(payload);
const response = await admin.messaging().sendToDevice(Token, payload)
console.info("Successfully sent notification")
responses.push(response);
});
};
return responses; //here
} catch (error) {
console.info("error", error)
}
});