I have a firebase application that uses Cloud Functions to talk to a Google Cloud SQL instance. These cloud functions are used to perform CRUD actions. I would like to ensure that the database reflects the CRUD operations, as such, run migration code every time I push new function code to ensure the database is always up to date.
I do this in a global function
const functions = require('firebase-functions')
const pg = require('pg')
// Create if not exists database
(function() {
console.log('create db...')
})()
exports.helloWorld = functions.https.onRequest((request, response) => {
console.log('Hello from Firebase function log!')
response.send('Hello from Firebase!')
})
exports.helloWorld2 = functions.https.onRequest((request, response) => {
console.log('Hello from Firebase function log 2!')
response.send('Hello from Firebase 2!')
})
This console log then runs twice when I deploy.
Now I understand that there is no way of knowing how many instances Cloud Functions will spin up for the functions, as stated in their docs:
The global scope in the function file, which is expected to contain the function definition, is executed on every cold start, but not if the instance has already been initialized.`
If I add a third function, this console log is now shown 3 times in the logs, instead of 2, one for each function. Would it be correct in saying that there's a new instance for every single function uploaded? I am trying to understand what happens under the hood when I upload a set of cloud functions.
If so - is there no reliable way to run migration code inside a global function in cloud functions?
