制作无限期运行的云http函数

Question

Answered in the comments by Chris G: Use setInterval instead, and remove the while loop; this code will call clearData in rapid succession, infinitely. (and a cronjob is definitely preferable to this setup, btw)

I need to make a http function that only calls one time (at launch) and after that runs every 5 minutes to check data and if that data is 2 hours old we clear it.

A few things before i show the code:

1. We know of google scheduler but are choosing not to use it.
2. We know we can use cron-jobs to call our html whenever we need but that would mean another service and my goal is to have the function run itself without any service like calling it.

Code:

const functions = require('firebase-functions');
const admin = require('firebase-admin');

admin.initializeApp(functions.config().firebase);

exports.methodCaller = functions.https.onRequest((request, response) => {
  setTimeout(() => {
    while (true) {
      clearData();
      console.log('methodCaller execution')
    }
  }, 30000); // currently 30 seconds for testing purposes but will be 5 hours later on
});

function dataChecked() {
  admin.database().ref('/logs/')
    .once("value")
    .then(snapshot => {
      console.log(snapshot.val());
      //code that checks data
    });
}

1. Is my way of timing out the function correct. I want it to manually fire every 5 minutes checking some data.

2. The http request wants a response but if i put it inside of the while(true) statement it only logs 2 times.

3. Is my code correct at all ?

Answer 1

I need to make a http function that only calls one time (at launch) and after that runs every 5 minutes to check data and if that data is 2 hours old we clear it.

For that you should use schedule functions, which are now supported under Firebase. See the blog post Scheduling Cloud Functions for Firebase (cron) , which contains this very relevant example for your use-case:

 export scheduledFunctionPlainEnglish = functions.pubsub.schedule('every 5 minutes').onRun((context) => { console.log('This will be run every 5 minutes!'); });

---

The way you're now trying to implement the use-case won't work. Cloud Functions has a hard upper limit of 9 minutes before it kills a function instance.

Answer 2

What you are wanting to do is impossible, the maximum time you can set for a cloud function in general is 540 seconds(9 Minutes).

I have one function that has that as the maximum timeout, but generally the timeout is 60 seconds. If you want to run something every 5 hours, just run it in a cron job, or set up a VPS and start the program there.

Cloud functions is not what you are looking for for this, plus you do not want to have to pay for the compute time for this.