Set a variable messagingSenderId in service worker (Firebase) [duplicate] - variables

Question

This question already has answers here:
Passing state info into a service worker before `install`
(2 answers)
Closed 5 years ago.
I would like to set a variable messagingSenderId value in my service worker, not an hardcoded one. Is it possible?
I register my service worker like this:
navigator.serviceWorker.register( 'firebase-messaging-sw.js' )
.then( function( registration ) {
messaging.useServiceWorker( registration );
});
And in my firebase-messaging-sw.js, I initialize firebase like this
importScripts('https://www.gstatic.com/firebasejs/3.9.0/firebase-app.js' );
importScripts('https://www.gstatic.com/firebasejs/3.9.0/firebase-messaging.js' );
firebase.initializeApp({
'messagingSenderId': 'my-id' // <- I want this to be variable
});
The problem is I can't find how to pass data to my service worker file. Any idea?
Thanks

Answer 1

As mentionned, Passing state info into a service worker before 'install' answered the question. Thanks.
Here is the answer for this use case:
You need to pass the variable in the URL like so:
var myId = 'write-your-messaging-sender-id-here';
navigator.serviceWorker.register( 'firebase-messaging-sw.js?messagingSenderId=' + myId )
.then( function( registration ) {
messaging.useServiceWorker( registration );
});
And then, in firebase service worker (firebase-messaging-sw.js), you can get this variable like so:
importScripts('https://www.gstatic.com/firebasejs/3.9.0/firebase-app.js' );
importScripts('https://www.gstatic.com/firebasejs/3.9.0/firebase-messaging.js' );
var myId = new URL(location).searchParams.get('messagingSenderId');
firebase.initializeApp({
'messagingSenderId': myId
});
This works. But URL.searchParams is a very new tool. It is less compatible than Firebase itself.
URL.searchParams: Chrome 51+, Firefox: 52+, Opera: unknown
Firebase: Chrome 50+, Firefox 44+, Opera 37+
So instead of:
var myId = new URL(location).searchParams.get('messagingSenderId');
I suggest using:
var myId = get_sw_url_parameters( 'messagingSenderId' );
function get_sw_url_parameters( param ) {
var vars = {};
self.location.href.replace( self.location.hash, '' ).replace(
/[?&]+([^=&]+)=?([^&]*)?/gi, // regexp
function( m, key, value ) { // callback
vars[key] = value !== undefined ? value : '';
}
);
if( param ) {
return vars[param] ? vars[param] : null;
}
return vars;
}