Node js Json add array - node.js

Question

This is my query
var db = firebase.database();
var ref = db.ref('Users');
ref.on('child_added', function(snapshot){
console.log(snapshot.val())
});
and this is out put
{ callCount: 1,
favoriteCount: 1,
interest: [ 'dogs', 'cats', 'technology' ],
tickCount: 1 }
{ callCount: 15,
favoriteCount: 7,
interest: [ 'Technology', 'Azure', 'Asp.NET MVC', 'JavaScript' ],
tickCount: 3 }
I want to add a array and show it like this
[{ callCount: 1,
favoriteCount: 1,
interest: [ 'dogs', 'cats', 'technology' ],
tickCount: 1 },
{ callCount: 15,
favoriteCount: 7,
interest: [ 'Technology', 'Azure', 'Asp.NET MVC', 'JavaScript' ],
tickCount: 3 }]
How can I do ?

Answer 1

This will not be possible with child_added event, because it never gives any indication about reaching the end of the dataset, and will continue to emit new items when they are added.
Instead, you should subscribe to the value which will emit snapshot of the full tree in the beginning and whenever anything changes.
Since you only need to get the value once, here's how you do it:
const db = firebase.database();
const ref = db.ref('Users');
ref.once('value', snapshot => {
const result = [];
snapshot.forEach(item => {
result.push(item.val());
return false;
});
// Do something with the result
});
A few things to note here:
We are subscribing to event using once since we are only interested in the initial value. If you want to react to changes in dataset somehow, you may use on instead.
We are using forEach to get to the snapshot value, instead of val because we care about the item order. forEach guarantees that the callback will be invoked with all of the snapshot keys in order, as specified by orderBy query. val on the other hand, would return an object with unreliable ordering of the keys.
forEach will stop as soon as the callback returns true, which we don't want to happen. Returning nothing will not cancel enumeration, but it's better to be explicit in case someone decides to be concise and removes the curly braces.