Firebase asynchronous function, what's in the background queue and what's not

Question

Lets say I have this

// a bunch of code...  
FIRDatabase.database.reference.child(\"somechild\").observeSingleEventOfType(.Value, withBlock{(snapshot) in           


        

Answer 1

That's indeed how the Firebase Database client works: all network and disk I/O happen off the main thread, then your callbacks/blocks are invoked on the main thread.