How to run method once at app launch .NET 6 MVC?

Question

How to run a method only once at app launch in .NET 6 MVC application. This method will use configured services to create default users/roles, seed some configuration data, and register HangFire background jobs.

Answer 1

If you want to run something after app.Run(), you might want to register to the IHostApplicationLifetime.ApplicationStarted event. Per MSDN, it is "Triggered when the application host has fully started.".

To register the event use the following code snippet:

app.Lifetime.ApplicationStarted.Register(() =>
    create default users/roles,
    seed some configuration data,
    and register HangFire background jobs
)