JobQueueCenter Dummy upload service

DocumentUploadService.swift

class DocumentUploadService : NSObject {
    var document: Data
    
    init(document: Data) {
        self.document = document
        super.init()
    }
    
    func execute(complete: @escaping (Bool)->Void) {
        //do something with the document argument
        print(document)
        
        //our long fake networking method
        DispatchQueue(label: "networking").asyncAfter(deadline: .now() + 5) {
            
            DispatchQueue.main.async {
                //let's say it only succeed after the second time to simulate unstable network
                if self.retryableCount == 1 {
                    complete(true)
                } else {
                    complete(false)
                }
            }
        }
    }