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Ag-grid: duplicate node id 107 detected from getRowNodeId callback , this could cause issues in your grid

I am going to do live data streaming on ag-grid datatable, so I used DeltaRowData for gridOptions and added getRowNodeId method as well which return unique value 'id'.
After all, I got a live update result on my grid table within some period I set, but some rows are duplicated so I can notice total count is a bit increased each time it loads updated data. The question title is warning message from browser console, I got bunch of these messages with different id number. Actually it is supposed not to do this from below docs. This is supposed to detect dups and smartly added new ones if not exist. Ofc, there are several ways to get refreshed data live, but I chose this one, since it says it helps to persist grid info like selected rows, current position of scroll on the grid etc. I am using vanilla js, not going to use any frameworks.
How do I make live data updated periodically without changing any current grid stuff? There is no error on the code, so do not try to speak about any bug. Maybe I am wrong with current implementation, Anyway, I want to know the idea or hear any implementation experience on this.
let gridOptions = {
....
deltaRowDataMode: true,
getRowNodeId = (data) => {
return data.id; // return the property you want set as the id.
}
}
fetch(loadUrl).then((res) => {
return res.json()
}).then((data) => {
gridOptions.api.setRowData(data);
})
...

If you get:
duplicated node warning
it means your getRowNodeId() has 1 value for 2 different rows.
here is part from source:
if (this.allNodesMap[node.id]) {
console.warn("ag-grid: duplicate node id '" + node.id + "' detected from getRowNodeId callback, this could cause issues in your grid.");
}
so try to check your data again.
if u 100% sure there is an error not related with your data - cut oof the private data, create a plinkr/stackblitz examples to reproduce your issue and then it would be simpler to check and help you.

Retrieve data from specific node in Firebase database using javascript

firebase snippit
Hello all. I am creating a web app that pulls from a firebase realtime database I have created. Using javascript I would like to pull the data from a specific node (i.e. "8").
I will then use the keys and values from the node in the web app.
What js/firebase code do I need to pull data from any specific node?
Below is the code we have tried. Long term goal is to pull data from a random node, but right now I just to find out how to pull from a specific node. Since the nodes are always going to be a number from 0-49, I don't need to use "length of array" functions when randomizing. I will use "Math.floor(Math.random() * 49" to give me a random number which I can pass into the index value for the node when I figure out how to access one specifically.
ref = firebase.database().ref('articles/');
function setupObservers() {
ref.on('value',function(snapshot){
console.log(snapshot.val())
let articleArray = []
for(key in snapshot.val()) {
let articleKeys = snapshot.val()[key]
articleArray.push(articleKeys)
}
randomArticle(articleArray)
})
}
function randomArticle(articleArray) {
let random = articleArray[Math.floor(Math.random() * articleArray.length)]
console.log(random)
}
setupObservers()
Thanks in advance!!

To read the value from a specific child node of which you know the key, you simply do:
ref = firebase.database().ref('articles');
ref.child("8").on('value',function(snapshot){
console.log(snapshot.val())
});

How do I display the followers count in real time using firebase?

I have an application where users can follow other users. I want to have a real-time update system, display the total count of followers a user has.
I've just started playing around with Firebase and Pusher, but I don't understand one thing - will each user have their own 'channel'? How would I handle such thing as a follower counter update?
I followed the tutorial and saw that push method can create lists, so one solution I can see is having a list of all the users, each user being an object something like this:
{ username: 'john_doe', follower_count: 6 }
But I don't understand how would I actually track it on the front end? Should I have a filter, something like this?
var user = users.filter(function(user) { return user.username === 'john_doe'; });
// code to display user.follower_count
Or is there a different way that I'm missing?

Most of Firebase logic is based on listeners, you can add a listener to events happening in your collections and when those events happen, you do something.
One way to go about this would be:
var myFollowerListRef = new Firebase(PATH_TO_YOUR_COLLECTION);
myFollowerListRef.on("value", function(snapshot) {
console.log(snapshot.length);
});
This way, every time your follower collection changes, the asynchronous function fires and you can do what you want with the fresh data.
For more information:
https://www.firebase.com/docs/web/guide/retrieving-data.html
Hope this helps, I'm still a beginner in Firebase.

#Th0rndike's approach is the simplest and works fine for relatively short lists. For longer lists, consider using a transaction. From the Firebase documentation on saving transactional data:
var upvotesRef = new Firebase('https://docs-examples.firebaseio.com/android/saving-data/fireblog/posts/-JRHTHaIs-jNPLXOQivY/upvotes');
upvotesRef.transaction(function (current_value) {
return (current_value || 0) + 1;
});
But I recommend that you read the entire Firebase guide. It contains solutions for a lot of common use-cases.

Subscribe to a count of an existing collection

I need to keep track of a counter of a collection with a huge number of documents that's constantly being updated. (Think a giant list of logs). What I don't want to do is to have the server send me a list of 250k documents. I just want to see a counter rising.
I found a very similar question here, and I've also looked into the .observeChanges() in the docs but once again, it seems that .observe() as well as .observeChanges() actually return the whole set before tracking what's been added, changed or deleted.
In the above example, the "added" function will fire once per every document returned to increment a counter.
This is unacceptable with a large set - I only want to keep track of a change in the count as I understand .count() bypasses the fetching of the entire set of documents. The former example involves counting only documents related to a room, which isn't something I want (or was able to reproduce and get working, for that matter)
I've gotta be missing something simple, I've been stumped for hours.
Would really appreciate any feedback.

You could accomplish this with the meteor-streams smart package by Arunoda. It lets you do pub/sub without needing the database, so one thing you could send over is a reactive number, for instance.
Alternatively, and this is slightly more hacky but useful if you've got a number of things you need to count or something similar, you could have a separate "Statistics" collection (name it whatever) with a document containing that count.

There is an example in the documentation about this use case. I've modified it to your particular question:
// server: publish the current size of a collection
Meteor.publish("nbLogs", function () {
var self = this;
var count = 0;
var initializing = true;
var handle = Messages.find({}).observeChanges({
added: function (id) {
count++;
if (!initializing)
self.changed("counts", roomId, {nbLogs: count});
},
removed: function (id) {
count--;
self.changed("counts", roomId, {nbLogs: count});
}
// don't care about moved or changed
});
// Observe only returns after the initial added callbacks have
// run. Now return an initial value and mark the subscription
// as ready.
initializing = false;
self.added("counts", roomId, {nbLogs: count});
self.ready();
// Stop observing the cursor when client unsubs.
// Stopping a subscription automatically takes
// care of sending the client any removed messages.
self.onStop(function () {
handle.stop();
});
});
// client: declare collection to hold count object
Counts = new Meteor.Collection("counts");
// client: subscribe to the count for the current room
Meteor.subscribe("nbLogs");
// client: use the new collection
Deps.autorun(function() {
console.log("nbLogs: " + Counts.findOne().nbLogs);
});
There might be some higher level ways to do this in the future.

node.js/javascript/couchdb view to associative array does not seem to work

I am trying to create a webapp on a node/couchdb/windows stack but get terribly stung by what seems to be a lack of experience.
In the database, there is a view that returns all users with passwords. Based on the tutorial for a blog I have tried to access the view through my node code.
Whenever I investigate the structure of the users or users variable, I get an undefined object.
The call to getDatabase() has been tested elsewhere and works at least for creating new documents.
function GetUser(login)
{
var users = GetUsers();
return users[login];
}
function GetUsers() {
var db = getDatabase();
var usersByEmail = [];
db.view("accounts", "password_by_email")
.then(function (resp) {
resp.rows.forEach(function (x) { usersByEmail[x.key] = x.value});
});
//usersByEmail['test'] = 'test';
return usersByEmail;
}
I am aware that both the use of non-hashed passwords as well as reading all users from the database is prohibitive in the final product - just in case anyone wanted to comment on that.
In case something is wrong with the way I access the view: I am using a design document called '_design/accounts' with the view name 'password_by_email'.

Your call to db.view is asynchronous, so when you hit return usersByEmail the object hasn't yet been populated. You simply can't return values from async code; you need to have it make a callback that will execute the code that relies on the result.