Javascript returns undefined between two js files

Question

I'm new to this development. Trying to retrieve some content from Firebase(readonlyfirebase.js) and pass it to node.js(mainNode.js) but variable 'content1' always received as 'undefined'. But variable 'num' received fine. Please help me to figure out what mistake am doing here. num declared outside of funtion. tried exporting content1 as well but not working.

mainNode.js

var http=require("http");  
const readjs = require('./readonlyfirebase');
    
const header_content = readjs.ReadFromFirebase();
console.log('displaying header content = ',readjs.header_content); -->**Displays undefined**

readonlyfirebase.js

var content1;

function ReadFromFirebase(){
var firebase = require("firebase");

var admin = require("firebase-admin");
var serviceAccount = require("./serviceAccountKey.json");

const firebaseConfig = {
    apiKey: "",
    ***details hidden*****
  };

  firebase.initializeApp(firebaseConfig)

var db = firebase.database();
var ref = db.ref("header_content");  

/* Reading Value from Firebase Data Object */  

ref.on("value", function(snapshot) {
    console.log(snapshot.val());
    content1 = snapshot.val();
    console.log('header before returning ',content1);
    return content1;
    //localStorage.setItem("localvar1", content1); 
  console.log('localstorage set');
  }, function (errorObject) {
    console.log("The read failed: " + errorObject.code);
  });


 
}


const num = 33;

module.exports = { ReadFromFirebase, num, content1};

header_content not a property of readjs, it is a constant, you should directly use that. — Rohit Khandelwal, May 05 '21 at 18:32
Tried exporting content1 like below but didn't work. module.exports = { ReadFromFirebase,content1}; — appsy, May 05 '21 at 18:38
@Rohit.. Accessed header_content directly without readjs.header_content still same issue. — appsy, May 05 '21 at 18:54
@appsy ReadFromFirebase function not returning anything, there is no return statement. Pls, check what this function wants to achieve? — Rohit Khandelwal, May 07 '21 at 05:38

score -1 · Answer 1 · answered May 05 '21 at 18:29

-1

try this in main.js

var http=require("http");  
const readjs = require('./readonlyfirebase');
    
const header_content = readjs.ReadFromFirebase();
console.log('displaying header content = ',header_content);

answered May 05 '21 at 18:29

Pratik Pathak

1

HI, There is no change from my code and what you suggested here. please highlight what you have changed – appsy May 05 '21 at 18:43

Javascript returns undefined between two js files

1 Answers1