iOS In App Purchase Example with appusername

FVRInAppPurchaseVC.swift

//
//  FVRInAppPurchaseVC.swift
//  favroutes
//
//  Created by wisaruthk on 10/8/2558 BE.
//  Copyright © 2558 kojo. All rights reserved.
//

import UIKit
import StoreKit

class FVRInAppPurchaseVC: UIViewController, SKProductsRequestDelegate, SKPaymentTransactionObserver {
    @IBOutlet weak var purchaseButton: UIButton!
    @IBOutlet weak var restorePurchaseButton:UIButton!
    
    var product_id:String?;
    var appusername:String?;

    override func viewDidLoad() {
        product_id = "item4";
        appusername = "favid@test.com";
        super.viewDidLoad()
        SKPaymentQueue.defaultQueue().addTransactionObserver(self)
        self.title = "In App Purchase"
        //
    }
    
    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        //
    }
    
    override func viewDidDisappear(animated: Bool) {
        super.viewDidDisappear(animated)
        SKPaymentQueue.defaultQueue().removeTransactionObserver(self)
    }
    
    @IBAction func buyConsumable(sender: AnyObject) {
        print("About to fetch the products");
        // We check that we are allow to make the purchase.
        if (SKPaymentQueue.canMakePayments())
        {
            let productID:Set<String> = Set<String>(arrayLiteral: self.product_id!)
            let productsRequest:SKProductsRequest = SKProductsRequest(productIdentifiers: productID);
            productsRequest.delegate = self;
            productsRequest.start();
            print("Fething Products");
        }else{
            print("can't make purchases");
        }
    }
    
    @IBAction func restorePurchase(sender:AnyObject){
        print("About to restore purchase");
        // For IAP with appusername
        SKPaymentQueue.defaultQueue().restoreCompletedTransactionsWithApplicationUsername(self.appusername)
        
        // For default
        // SKPaymentQueue.defaultQueue().restoreCompletedTransactions();
    }
    
    
    // Helper Methods
    func buyProduct(product: SKProduct){
        print("Sending the Payment Request to Apple");
        // For IAP with appusername
        let payment:SKMutablePayment = SKMutablePayment(product: product)
        payment.applicationUsername = self.appusername!;
        print("payment request with appusername = \(payment.applicationUsername)");
        
        // For default
        //var payment = SKPayment(product: product)
        
        SKPaymentQueue.defaultQueue().addPayment(payment);
        
    }
    
    // Delegate Methods for IAP
    
    func productsRequest (request: SKProductsRequest, didReceiveResponse response: SKProductsResponse) {
        print("got the request from Apple")
        let count : Int = response.products.count
        if (count>0) {
            let validProducts = response.products
            let validProduct: SKProduct = response.products[0] as SKProduct
            if (validProduct.productIdentifier == self.product_id) {
                print(validProduct.localizedTitle)
                print(validProduct.localizedDescription)
                print(validProduct.price)
                buyProduct(validProduct);
            } else {
                print(validProduct.productIdentifier)
            }
        } else {
            print("nothing")
        }
    }
    
    
    func request(request: SKRequest!, didFailWithError error: NSError!) {
        print("Request fail with error \(error.localizedDescription)");
    }
    
    // Delegate for SKPaymentTransactionObserver
    func paymentQueue(queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction])
    {
        print("Received Payment Transaction Response from Apple");
        for transaction:SKPaymentTransaction in transactions {
            if let trans:SKPaymentTransaction = transaction {
                switch trans.transactionState {
                case .Purchased:
                    print("Product Purchased");
                    //For IAP With appusername
                    print("tran with appuser = \(trans.payment.applicationUsername)")
                    
                    SKPaymentQueue.defaultQueue().finishTransaction(trans)
                    break;
                case .Failed:
                    print("Purchased Failed with \(trans.error)");
                    SKPaymentQueue.defaultQueue().finishTransaction(trans)
                    break;
                    // case .Restored:
                    //[self restoreTransaction:transaction];
                default:
                    break;
                }
            }
        }
        
    }
    
    // Sent when an error is encountered while adding transactions from the user's purchase history back to the queue.
    func paymentQueue(queue: SKPaymentQueue, restoreCompletedTransactionsFailedWithError error: NSError){
        print("restore completed but failed with error \(error.localizedDescription)");
    }
    
    // Sent when all transactions from the user's purchase history have successfully been added back to the queue.
   
    func paymentQueueRestoreCompletedTransactionsFinished(queue: SKPaymentQueue){
        print("restore completed with queue \(queue.transactions[0].payment.productIdentifier)");
    }
}