How to handle multiple firebase projects server side?

Question

I have SaaS application that needs 4 mobile apps (built in Flutter):

• iOS/Android version of a customer app
• iOS/Android version of admin app

Initially, I was thinking of having a single Firebase project where all 4 apps reside, but I have read that this may not be the best way to handle things (Firebase FCM, multiple apps in the same firebase project).

I have no issues breaking it up to two Firebase projects, one for the customer app and one for the admin app, but how do I then handle this server side when my API is to send pushes?

Server is using .Net, and right now I am using Global.asmx to create the firebase instance:

protected void Application_Start(object sender, EventArgs e)
{
    // Enable firebase
    FirebaseApp.Create(new AppOptions() { Credential = GoogleCredential.FromFile(HostingEnvironment.MapPath(@"~/App_Data/customerapp-245105.json")).CreateScoped("https://www.googleapis.com/auth/firebase.messaging") });
}

But this will only enable the customer app? How do I also create the admin app?

Im assuming that I can't simply do:

protected void Application_Start(object sender, EventArgs e)
{
    // Enable firebase
    FirebaseApp.Create(new AppOptions() { Credential = GoogleCredential.FromFile(HostingEnvironment.MapPath(@"~/App_Data/customerapp-245105.json")).CreateScoped("https://www.googleapis.com/auth/firebase.messaging") });

    FirebaseApp.Create(new AppOptions() { Credential = GoogleCredential.FromFile(HostingEnvironment.MapPath(@"~/App_Data/adminapp-244405.json")).CreateScoped("https://www.googleapis.com/auth/firebase.messaging") });
}

And, how do I tell the instances apart when calling them in the webservice? As the first instance would be used when sending pushes to customers, and the second for admin?

Solution

Each FirebaseApp instance must be given a unique name. You can look up instances by their names. See the examples in the documentation: https://firebase.google.com/docs/admin/setup#initialize_multiple_apps

Comments

[Robert Benedetto]

Yeah, turns out it was as easy as that. Just add the instance name as a parameter when calling .Create(), then get the instance using FirebaseApp.GetInstance("<instance name>");