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Is there anyway i can update a firestore document automatically even if app is closed, is there a listeener or something

i have a firestore and project that needs to be updated automatically without user interaction but i do not know how to go about it, any help would be appreciated. take a look at the json to understand better
const party = {
id: 'bgvrfhbhgnhs',
isPrivate: 'true',
isStarted: false,
created_At: '2021-12-26T05:20:29.000Z',
start_date: '2021-12-26T02:00:56.000Z'
}
I want to update the isStarted field to true once the current time is equal to start_date

I think you will need Firebase Cloud Function, although I don't understand exactly what you mean.
With Cloud Functions, you can automatically run (add, delete, update, everything) codes on Google's Servers without the need for application and user interaction.
For example, in accordance with your example, it can automatically set "isStarted" to true when it hits the "start_date" time. If you want to code a system that does not require user interaction and should work automatically, you should definitely use Cloud Functions. Otherwise, you cannot do this on the application side.
For more info visit Cloud Functions

Ok, I managed to find a workaround to updating my documents automatically without user interaction since the google billing service won’t accept my card to enable cloud functions for my project, I tried what I could to make my code work and I don’t know if other peeps would follow my idea or if my idea would solve similar issues.
What I did was that in my nextjs file I created an API endpoint to fetch and update documents after installing the firebase admin SDK, so I fetched all documents and converted all start_date fields in each document to time and checked for documents whose start date is less than or equal to current date, so after getting the document, I ran a firestore function to Update the document.
Tho this will only run when you make a request to my domain.com/api/update-parties and never run again
In other to make it run at scheduled intervals, I signed up for a free tier account at https://www.easycron.com and added my API endpoint to EASYCRON to make requests to my endpoint at a minute interval, so when the request hits my endpoint, it runs my code like other serverless functions😜. Easy peezy.

Firestore suddenly has a huge trigger delay

We are running an application on Firestore and got a simple trigger that when order's details are created or updated some of it's information should be rewritten in the parent order collection.
The function for this got following code
export const updateOrderDetails = functions
.region(FUNCTION_REGION)
.firestore.document("orders/{orderId}/details/pickupAndDropoff")
.onWrite(async (change, context) => {
return await admin
.firestore()
.collection("orders")
.doc(context.params.orderId)
.set({ pickupAndDropoff: change.after.data() }, { merge: true });
});
It was work fine before, but now at random about every third of its executions is delayed. Sometimes by few minutes. In Cloud Function logs we see normal execution times <200ms, so it seems the trigger runs after a huge pause.
What's worse from time to time our change.after.data() is undefined, but we never delete anything - it's just updates and creates.
It was working fine, we did not changed nothing since last week, but now it started to have this unexpected delays. We've also checked the firebase status, but there are no malfunctions in firebase functions service. What can be the cause of this?

The problem can be due to the monotonically increasing orderId as the parameter passed here:
...
.collection("orders")
.doc(context.params.orderId)
...
If you can check once if the orderId passed here is monotonically increasing with each request? It can lead to hotspots which impacts latency.
To explain, I think the write rate must be changing at different day's and time's - as the user traffic using the application or load testing requests changes - which is creating the unexpected kind of behaviour. At low write rate, the requests are working as expected most of the time. At high write rate, the requests are facing hotspot situation in the firestore as mentioned in the firestore documentation resulting in delays (latency issue).
Here is the relevant link to firestore best practices documentation.

Thanks to Frank van Puffelen suggestion we've sent this question directly to Firebase support and after their internal investigation we've got the reply from an engineering team that it was in fact an infrastructure malfunction.
The reply I got from them was:
I escalated the issue to recover more information. So far it appears that there was an issue with pub/sub delivering and creating the event. The Firestore team is also communicating with the pub/sub team to investigate the issue and prevent future incidents.
It seems that the best way to deal with such problems is to quickly write directly to Firebase support team, because as they mentioned in the automatic reply I got after sending a support ticket:
For Firebase outages not listed on the status dashboard, we'll respond within 4 hours.
which seems to be the best option.

Can't change data in Firebase Realtime Database when using Cloud Functions

I want to reset a specific value in my Firebase Realtime Database every day at 12:00 AM. I'm using Firebase Cloud Functions to do this. This is the code that I have:
exports.dailyReset = functions.pubsub.schedule('0 0 * * *').onRun((context) => {
exports.resetValue = functions.database.ref('/users/{userId}')
.onWrite((change, context) => {
var ref = change.data.ref;
ref.update({
"daily": 0
});
return ref.update({"daily": 0});
});
return null;
});
Upon testing the script, it doesn't work. It's not resetting the value in my Firebase Realtime Database. Can someone tell me how do I fix this?

It's not possible to use the Functions SDK to write to the database. functions can only be used to establish triggers that run when the triggering event occurs.
In other words, functions.database.ref('/users/{userId}').onWrite() isn't going to write anything at all.
If you want to write to Realtime Database from a nodejs program, you should use the Firebase Admin SDK to write data.

The Cloud Functions triggers in your index.js file have to be known and fixed when run firebase deploy. That means you can't dynamically create triggers from inside a Cloud Functions, as you're trying to do.
The common approaches for dynamic scheduling are:
Have a single Cloud Function that runs periodically and then executes the tasks for the past time period.
Dynamically schedule Cloud Functions with Cloud Tasks, as Doug describes in his blog post How to schedule a Cloud Function to run in the future with Cloud Tasks (to build a Firestore document TTL).
But in your case, why do you even need the onWrite trigger? Can't you just import the Admin SDK, user that to read all users, and then delete them?

Best way to have a Node.JS server keep updated with a FireBase database in real time?

I currently have a Node.JS server set up that is able to read and write data from a FireBase database when a request is made from a user.
I would like to implement time based events that result in an action being performed at a certain date or time. The key thing here though, is that I want to have the freedom to do this in seconds (for example, write a message to console after 30 seconds have passed, or on Friday the 13th at 11:30am).
A way to do this would be to store the date/time an action needs be performed in the database, and read from the database every second and compare the current date/time with events stored so we know if an action needs to be performed at this moment. As you can imagine though, this would be a lot of unnecessary calls to the database and really feels like a poor way to implement this system.
Is there a way I can stay synced with the database without having to call every second? Perhaps I could then store a version of the events table locally and update this when a change is made to the database? Would that be a better idea? Is there another solution I am missing?
Any advice would be greatly appreciated, thanks!
EDIT:
How I currently initialise the database:
firebase.initializeApp(firebaseConfig);
var database = firebase.database();
How I then get data from the database:
await database.ref('/').once('value', function(snapshot){
snapshot.forEach(function(childSnapshot){
if(childSnapshot.key === userName){
userPreferences = childSnapshot.val().UserPreferences;
}
})
});

The Firebase once() API reads the data from the database once, and then stops observing it.
If you instead us the on() API, it will continue observing the database after getting the initial value - and call your code whenever the database changes.

It sounds like you're looking to develop an application for scheduling. If that's the case you should check out node-schedule.
Node Schedule is a flexible cron-like and not-cron-like job scheduler
for Node.js. It allows you to schedule jobs (arbitrary functions) for
execution at specific dates, with optional recurrence rules. It only
uses a single timer at any given time (rather than reevaluating
upcoming jobs every second/minute).
You then can use the database to keep a "state" of the application so on start-up of the application you read all the upcoming jobs that will be expected and load them into node-schedule and let node-schedule do the rest.

The Google Cloud solution for scheduling a single item of future work is Cloud Tasks. Firebase is part of Google Cloud, so this is the most natural product to use. You can use this to avoid polling the database by simply specifying exactly when some Cloud Function should run to do the work you want.
I've written a blog post that demonstrates how to set up a Cloud Task to call a Cloud Functions to delete a document in Firestore with an exact TTL.

Is there a way to setup an self destructing value on Firebase real time database or firestore? [duplicate]

I am looking for a way to schedule Cloud Functions for Firebase or in other words trigger them on a specific time.

Update 2019-04-18
There is now a very simple way to deploy scheduled code on Cloud Functions through Firebase.
You can either use a simple text syntax:
export scheduledFunctionPlainEnglish =
functions.pubsub.schedule('every 5 minutes').onRun((context) => {
console.log('This will be run every 5 minutes!');
})
Or the more flexible cron table format:
export scheduledFunctionCrontab =
functions.pubsub.schedule('5 11 * * *').onRun((context) => {
console.log('This will be run every day at 11:05 AM UTC!');
});
To learn more about this, see:
The Scheduling Cloud Functions for Firebase blog post introducing the feature.
The documentation on scheduled functions.
Note that your project needs to be on a Blaze plan for this to work, so I'm leaving the alternative options below for reference.
If you want to schedule a single invocation of a Cloud Function on a delay from within the execution of another trigger, you can use Cloud Tasks to set that up. Read this article for an extended example of how that can work.
Original answer below...
There is no built-in runat/cron type trigger yet.
For the moment, the best option is to use an external service to trigger a HTTP function periodically. See this sample in the functions-samples repo for more information. Or use the recently introduced Google Cloud Scheduler to trigger Cloud Functions through PubSub or HTTPS:
I also highly recommend reading this post on the Firebase blog: How to Schedule (Cron) Jobs with Cloud Functions for Firebase and this video: Timing Cloud Functions for Firebase using an HTTP Trigger and Cron.
That last link uses cron-job.org to trigger Cloud Functions, and works for projects that are on a free plan. Note that this allows anyone to call your function without authorization, so you may want to include some abuse protection mechanism in the code itself.

What you can do, is spin up an AppEngine instance that is triggered by cron job and emits to PubSub. I wrote a blog post specifically on that, you might want to take a look:
https://mhaligowski.github.io/blog/2017/05/25/scheduled-cloud-function-execution.html

It is important to first note that the default timezone your functions will execute on is America/Los_Angeles according to the documentation. You may find a list of timezones here if you'd like to trigger your function(s) on a different timezone.
NB!!: Here's a useful website to assist with cron table formats (I found it pretty useful)
Here's how you'd go about it:
(Assuming you'd like to use Africa/Johannesburg as your timezone)
export const executeFunction = functions.pubsub.schedule("10 23 * * *")
.timeZone('Africa/Johannesburg').onRun(() => {
console.log("successfully executed at 23:10 Johannesburg Time!!");
});
Otherwise if you'd rather stick to the default:
export const executeFunction = functions.pubsub.schedule("10 23 * * *")
.onRun(() => {
console.log("successfully executed at 23:10 Los Angeles Time!!");
});