iOS应用程序购买 - 自动续订订阅

Question

亲爱的，

我有一个关于ios应用程序购买的问题，具体针对“自动续订订阅”我开发的应用程序包含免费功能和付费功能：基于“每月订阅和用户免费试用1周”的付费功能

并且所有过程都很好：我们将获取产品并且用户可以购买并且我们将验证收据（我知道食谱包含“is_trial ..”和“Purchase_date”的标志......）......

请注意：我在购买后或恢复后称之为“验证食谱”

但我有以下问题：我怎么知道以下内容：

1-如果用户第二次打开应用程序，我怎么知道用户是否还在试用期？

2-如果用户在1个月后打开应用程序：我怎么知道订阅是否过期...（所以如果订阅过期，我将再次购买电话......）

，每当用户打开应用程序时，我将称之为“验证食谱”的解决方案，因此我可以知道用户是否处于付费或付费期后（已过期）...

或者我会在本地保存购买日期（例如：用户默认）＆当用户打开应用程序时我会将当前日期与购买日期进行比较，实际上我不认为这是一个真正的答案，因为用户可能会更改设备日期....

请指教 …

代码如下：

所以现在打开app时：我要求产品：

SKPaymentQueue.default().add(self)
        if(SKPaymentQueue.canMakePayments()) {
            print("IAP is enabled, loading")


            let productID: NSSet = NSSet(objects: "test.test1.test2.11")



            let request: SKProductsRequest = SKProductsRequest(productIdentifiers: productID as! Set<String>)
            request.delegate = self
            request.start()
        } else {
            print("please enable IAPS")
        }

收到产品时：

  func productsRequest(_ request: SKProductsRequest, didReceive response: SKProductsResponse) {
        print("product request")
        let myProduct = response.products
        for product in myProduct {


            list.append(product)
        }
}

现在当用户按下按钮时：

for product in self.list {
        let prodID = product.productIdentifier
        if(prodID == "test.test1.test2.11") {
            self.p = product
            self.buyProduct()

        }
    }

下面的方法将调用

 func paymentQueue(_ queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
        print("add payment")

        for transaction: AnyObject in transactions {
            let trans = transaction as! SKPaymentTransaction

            switch trans.transactionState {
            case .purchased:
                receiptValidation()
                queue.finishTransaction(trans)

                break
            case .failed:
                print("buy error")
                queue.finishTransaction(trans)
                break
            default:
                print("Default")
                break
            }
        }
    }

我将验证收据：

func receiptValidation() {
        if let appStoreReceiptURL = Bundle.main.appStoreReceiptURL,
            FileManager.default.fileExists(atPath: appStoreReceiptURL.path) {

            do {
                let receiptData = try Data(contentsOf: appStoreReceiptURL, options: .alwaysMapped)

                let receiptString = receiptData.base64EncodedString(options: [])
                let dict = ["receipt-data" : receiptString, "password" : "xxxxxxxxxxx"] as [String : Any]

                do {
                    let jsonData = try JSONSerialization.data(withJSONObject: dict, options: .prettyPrinted)

                    if let sandboxURL = Foundation.URL(string:"https://sandbox.itunes.apple.com/verifyReceipt") {
                        var request = URLRequest(url: sandboxURL)
                        request.httpMethod = "POST"
                        request.httpBody = jsonData
                        let session = URLSession(configuration: URLSessionConfiguration.default)
                        let task = session.dataTask(with: request) { data, response, error in
                            if let receivedData = data,
                                let httpResponse = response as? HTTPURLResponse,
                                error == nil,
                                httpResponse.statusCode == 200 {
                                do {
                                    if let jsonResponse = try JSONSerialization.jsonObject(with: receivedData, options: JSONSerialization.ReadingOptions.mutableContainers) as? Dictionary<String, AnyObject> {

        } else { print("Failed to cast serialized JSON to Dictionary<String, AnyObject>") }
                                }
                                catch { print("Couldn't serialize JSON with error: " + error.localizedDescription) }
                            }
                        }
                        task.resume()
                    } else { print("Couldn't convert string into URL. Check for special characters.") }
                }
                catch { print("Couldn't create JSON with error: " + error.localizedDescription) }
            }
            catch { print("Couldn't read receipt data with error: " + error.localizedDescription) }
        }
    }