Trigger cloud function on specific date and time firebase - flutter

I want to change a document value at a specific date time in firestore, I don't want to use a scheduleFunctions of firebase i think it is costly to see every minute or an hour to check. Is there any better option which will trigger right on the given time etc.??. And it should be one time not a periodic call using flutter web and firebase for it

You could use the Google Cloud Scheduler to hit a HTTP Cloud Function periodically but using scheduled functions is your best bet.
Firebase had a very generous free tier. You mentioned you are “checking” every couple minutes or hours. That sounds like you updating a document based on an event, in which case you can use PubSub or Firestore triggered cloud functions.

Related

flutter/firebase schedule a function at given time

I want to schedule the cloud function at a specific time and that time will be in firestore document.I want that when i add data inside firestore, a cloud function will trigger and get data from that latest added document and will fetch date and time from that document data and then schedule a cloud function at that specific time to perform a specific task (update status in firestore).
For the time scheduling check this official documentation out:
https://firebase.google.com/docs/functions/schedule-functions
If you want to execute code on database changes check the triggers out:
https://firebase.google.com/docs/functions/database-events
You will need something like onUpdate(). Depends on your needs.
You can store files in the firebase storage. Check out the official documentation for a code example.
https://firebase.google.com/docs/storage/web/list-files
In case you want to read data from the firebase in your Flutter app, you can implement the flutter-firebase packages.
Here you can find the instructions for all firebase packages:
https://firebase.flutter.dev/
Stack Overflow is for asking questions. Your Question sounds more like you expecting that someone will give you the whole code, so you don't have to do any research about that.
If that's not the case, sorry for the misunderstanding.
Cloud Functions trigger for Firestore writes. There is nothing built in to trigger them at a time that is specific in the document that is written.
But you can build that yourself using Cloud Tasks, as Doug shows in this excellent blog post: How to schedule a Cloud Function to run in the future with Cloud Tasks (to build a Firestore document TTL)
I used the node-schedule package inside the Firebase Cloud Functions, after which I was able to schedule tasks at dynamic times from FireStore.
Here is sample code:
exports.scheduleMessage=functions.firestore.document('users/{userID}/pending/{messageID}').onCreate(async (snapshot,context) =>{
schedule.scheduleJob(messageId,`myDate.getUTCMinutes()
myDate.getUTCHours() * * *`, async () =>{
// your logic inside
});
});

how to achieve push Notifications without using firebase Cloud functions?

my APP Is Really Depends on push Notifications, for examples iF the app has two actors, owner, and user, if the owner posts something, the user must be notified, based on their locations and Engagement in the app, which means the System first searches the nearest user and notify him, Notification is performed based on the location of the user, the user who is found in the nearest location is notified first, so What I want to ask you is, is it possible to achieve this without using firebase Cloud functions, Since firebase Cloud functions are NOT Free at this time. it asks me Billing account but the payment method is not available in my country
Apologies for my previous reply, I misunderstood the situation,
Also another solution besides one signal, you can use FCM on your own server, via FirebaseAdmin SDK. If you have a NodeJS server, a simple one, you can perform all firebase functions on it. In the end, it's not an absolute necessity to use cloud functions, it's just more convenient for a simple task or a few functions than spinning up your own server just for notifications. I would advise to go with this solution, and you will have access to cloud firestore via the admin SDK, you'll feel right at home.
Firebase cloud functions requires billing info, but you aren't charged. You have 2 MILLION free api calls per month. Then every extra 1 million calls cost less than half a dollar.
Do you know what 2 Million API invocations per month means? That's 32 THOUSAND API calls per day. If your app is generating that much traffic, trust me, you will not be worrying about these costs.
You can use OneSignal if you want, but it's more work for you, and it's outside the Firebase ecosystem.
Go with cloud functions, when you are reaching the limit of the free tier of 2Million monthly API requests, you can start looking for investors in your app.

how to create backgroud service in flutter

how to create a background service in FLUTTER
with posh notification
I create an app but I went to integer a service to check the database when the app is not run
thank tou
I would recommend using Google Cloud Scheduler, which allows you to create CRON jobs which can send a request to your API, on a regular basis. The first three jobs are free.
If you also need to implement the actual function checking your database, have a look at Google Cloud Functions. Those can be written in Javascript or Typescript and call make calls to external APIs as long as you are on Blaze Plan (which includes the monthly free quotas).
The advantages are:
you get free credit when you create your account
depending on your needs you might not need more than the free monthly quota for Google Functions calls (first 2 millions invocations are free every month)
it's very easy to create a scheduled function which will picked up and run by the Cloud Scheduler
it's highly scalable and reliable so you don't have to worry about managing your own servers

The best practices for running CloudFunctions regularly based on the timestamp of each user

We are developing an app on Flutter on the client side and Firebase on the server side. I'm thinking of running Cloud Functions regularly using Cloud Scheduler based on each user's timestamp.
My idea is to run Cloud Functions using Cloud Scheduler every day at 12:00. Only users who have a timestamp older than 10 days perform a specific action. Is this a best practice?
Or is it possible to process Cloud Functions using the user's timestamp as a trigger?
For example, Cloud Functions is triggered when 10 days have passed since the user's timestamp.
Update
The scenario is as follows.
Cloud Firestore
/user/${userId}/funcStatus/status

Document(status) field is
timestamp:last update date(e.g. 2019/10/31)


I want to execute Cloud Function after 10 days, that is, when it becomes 11/10.

However, the timestamp varies depending on the user. e.g, userA:10/31, userB:10/20
The first option is possible with scheduled functions.
The second option is not possible with scheduled functions alone. You would have to use a Firestore onCreate trigger, then set up a callback with Cloud Tasks to get the function to execute at the right time.
Whichever one you choose is a matter of preference and whatever meets the needs of your app. There is no right or wrong way.

Run a Google Cloud Function for each file in a bucket

I have a Google Cloud Function triggered by a Google Cloud Storage object.finalize event. When I deploy a new version of this function, I would like to run it for every existing file in the bucket (which have already been processed by the previous version of the function). Processing all the existing files in the bucket is a long running task, hence I don't think a Google Cloud Function which will process all files in a row is an option.
The best option I can see for now is to make a Google Cloud Function I can triggered via HTTP that will list all the files in the bucket and publish one event per file via Google PubSub, and then process each of these events with a slightly modified version of my initial Google Cloud Function which accepts a PubSub event in place of the object.finalize storage event.
I think it can work but I was wondering if there was an easier way to perform this operation.
If the operation you're trying to perform may take longer than the maximum time that a Cloud Function can run, you will need to split that operation into multiple steps. Your approach of using a PubSub trigger for each individual file, sounds like a valid approach to do that for me.
One option might be to write a small program that lists all of the objects in a bucket and, for each object, posts a message to Cloud Pub/Sub that triggers your function in the same way a GCS change would.