Polling with RxSwift and Parse-Server - ios

Question

I'm working on an Apple TV app that uses Parse-Server as a backend and RxSwift and I'm trying to set up an authentication system similar to those on the tv streaming apps.
Right now I have an AuthenticationCode object in the parse database that has a code, device id, and session token column. I'm trying to use RxSwift's interval to perform a fetch on the object every 5 seconds, and am checking if the session token column has been filled out.
Here is the code:
func poll(authorizationCode: AuthorizationCode) -> Observable<AuthorizationCode> {
return Observable<Int>.interval(5, scheduler: MainScheduler.instance).flatMap({ _ in
return Observable<AuthorizationCode>.create { observer -> Disposable in
authorizationCode.fetchInBackground(block: { (authorizationCode, error) in
if let authorizationCode = authorizationCode as? AuthorizationCode {
observer.onNext(authorizationCode)
if authorizationCode.sessionToken != nil {
observer.onCompleted()
}
} else if let error = error {
observer.onError(error)
}
})
return Disposables.create()
}
})
}
I'm emitting on onNext event every time I fetch the object, and I want to terminate the sequence when the session code exists.
The problem I'm having with this code is that even after the session token is filled out and the onCompleted is called, the timer still fires and the subscriber never gets the onCompleted event.
Any help with this is appreciated.
Also, if I'm way off on how I should be doing this, let me know.
I would use Parse-Server live queries but they currently don't support tvOS.
Thanks.

Answer 1

UPDATED:
Try this:
func poll(authorizationCode: AuthorizationCode) -> Observable<AuthorizationCode> {
// 1. Return the Observable
return Observable<AuthorizationCode>.create { observer -> Disposable in
// 2. We create the interval here
let interval = Observable<Int>.interval(.seconds(5), scheduler: MainScheduler.instance)
// 3. Interval subscription
let subscription =
interval.subscribe(onNext: { _ in
// 4. Fetch
authorizationCode.fetchInBackground(block: { (authorizationCode, error) in
// 5. onNext, onCompleted, onError
if let authorizationCode = authorizationCode as? AuthorizationCode {
observer.onNext(authorizationCode)
if authorizationCode.sessionToken != nil {
observer.onCompleted()
}
} else if let error = error {
observer.onError(error)
}
})
})
return Disposables.create{
subscription.dispose()
}
}
}