AppStoreReceipt: refactor

3 files changed, 80 insertions, 62 deletions

diff --git a/ios/MullvadVPN.xcodeproj/project.pbxproj b/ios/MullvadVPN.xcodeproj/project.pbxproj
index 15263a1696..12f9d22b1e 100644
--- a/ios/MullvadVPN.xcodeproj/project.pbxproj
+++ b/ios/MullvadVPN.xcodeproj/project.pbxproj
@@ -54,6 +54,7 @@
 		5845F843236CBDAB00B2D93C /* PacketTunnelIpc.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5845F841236CBACD00B2D93C /* PacketTunnelIpc.swift */; };
 		5846226726E0DF960035F7C2 /* Promise+OperationQueue.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5846226626E0DF960035F7C2 /* Promise+OperationQueue.swift */; };
 		5846226826E0DF960035F7C2 /* Promise+OperationQueue.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5846226626E0DF960035F7C2 /* Promise+OperationQueue.swift */; };
+		5846226A26E0E6FA0035F7C2 /* ReceiptRefreshOperation.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5846226926E0E6FA0035F7C2 /* ReceiptRefreshOperation.swift */; };
 		584789B8264D4A2A000E45FB /* old_le_root_cert.cer in Resources */ = {isa = PBXBuildFile; fileRef = 584789B4264D4A2A000E45FB /* old_le_root_cert.cer */; };
 		584789B9264D4A2A000E45FB /* old_le_root_cert.cer in Resources */ = {isa = PBXBuildFile; fileRef = 584789B4264D4A2A000E45FB /* old_le_root_cert.cer */; };
 		584789BE264D4A2A000E45FB /* new_le_root_cert.cer in Resources */ = {isa = PBXBuildFile; fileRef = 584789B7264D4A2A000E45FB /* new_le_root_cert.cer */; };
@@ -339,6 +340,7 @@
 		584592602639B4A200EF967F /* ConsentContentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ConsentContentView.swift; sourceTree = "<group>"; };
 		5845F841236CBACD00B2D93C /* PacketTunnelIpc.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PacketTunnelIpc.swift; sourceTree = "<group>"; };
 		5846226626E0DF960035F7C2 /* Promise+OperationQueue.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Promise+OperationQueue.swift"; sourceTree = "<group>"; };
+		5846226926E0E6FA0035F7C2 /* ReceiptRefreshOperation.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ReceiptRefreshOperation.swift; sourceTree = "<group>"; };
 		584789B4264D4A2A000E45FB /* old_le_root_cert.cer */ = {isa = PBXFileReference; lastKnownFileType = file; path = old_le_root_cert.cer; sourceTree = "<group>"; };
 		584789B7264D4A2A000E45FB /* new_le_root_cert.cer */ = {isa = PBXFileReference; lastKnownFileType = file; path = new_le_root_cert.cer; sourceTree = "<group>"; };
 		584789DF26529D72000E45FB /* SSLPinningURLSessionDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SSLPinningURLSessionDelegate.swift; sourceTree = "<group>"; };
@@ -530,6 +532,7 @@
 				580EE22324B3243100F9D8A1 /* AsyncBlockOperation.swift */,
 				58E973DD24850EB600096F90 /* AsyncOperation.swift */,
 				580EE20524B3222200F9D8A1 /* ExclusivityController.swift */,
+				5846226926E0E6FA0035F7C2 /* ReceiptRefreshOperation.swift */,
 			);
 			path = Operations;
 			sourceTree = "<group>";
@@ -1135,6 +1138,7 @@
 				58FEEB58260B662E00A621A8 /* AutomaticKeyboardResponder.swift in Sources */,
 				58FAEDEF245069C700CB0F5B /* KeychainAttributes.swift in Sources */,
 				58CB0EE024B86751001EF0D8 /* MullvadRest.swift in Sources */,
+				5846226A26E0E6FA0035F7C2 /* ReceiptRefreshOperation.swift in Sources */,
 				58E1337526D2BEC400CC316B /* Promise+Optional.swift in Sources */,
 				58293FB125124117005D0BB5 /* CustomTextField.swift in Sources */,
 				582AE3102440A6CA00E6733A /* AccountTokenInput.swift in Sources */,
diff --git a/ios/MullvadVPN/AppStoreReceipt.swift b/ios/MullvadVPN/AppStoreReceipt.swift
index 9ced1bad7d..200d6ba1df 100644
--- a/ios/MullvadVPN/AppStoreReceipt.swift
+++ b/ios/MullvadVPN/AppStoreReceipt.swift
@@ -40,8 +40,26 @@ enum AppStoreReceipt {
         return queue
     }()
 
+    /// Read AppStore receipt from disk or refresh it from AppStore if it's missing.
+    /// This call may trigger a sign in with AppStore prompt to appear.
+    static func fetch(forceRefresh: Bool = false, receiptProperties: [String: Any]? = nil) -> Result<Data, Error>.Promise {
+        if forceRefresh {
+            return refreshReceipt(receiptProperties: receiptProperties)
+        } else {
+            return self.readFromDisk()
+                .asPromise()
+                .flatMapErrorThen { error in
+                    if case .doesNotExist = error {
+                        return refreshReceipt(receiptProperties: receiptProperties)
+                    } else {
+                        return .failure(error)
+                    }
+                }
+        }
+    }
+
     /// Read AppStore receipt from disk
-    static func readFromDisk() -> Result<Data, Error> {
+    private static func readFromDisk() -> Result<Data, Error> {
         guard let appStoreReceiptURL = Bundle.main.appStoreReceiptURL else {
             return .failure(.doesNotExist)
         }
@@ -56,70 +74,20 @@ enum AppStoreReceipt {
         }
     }
 
-    /// Read AppStore receipt from disk or refresh it from the AppStore if it's missing
-    /// This call may trigger a sign in with AppStore prompt to appear
-    static func fetch(forceRefresh: Bool = false, receiptProperties: [String: Any]? = nil,
-                      completionHandler: @escaping (Result<Data, Error>) -> Void)
-    {
-        if forceRefresh {
-            refreshReceipt(receiptProperties: receiptProperties,
-                           completionHandler: completionHandler)
-        } else {
-            switch self.readFromDisk() {
-            case .success(let data):
-                completionHandler(.success(data))
-
-            case .failure(let error):
-                // Refresh the receipt from AppStore if it's not on disk
-                if case .doesNotExist = error {
-                    refreshReceipt(receiptProperties: receiptProperties,
-                                   completionHandler: completionHandler)
-                } else {
-                    completionHandler(.failure(error))
-                }
+    /// Refresh receipt from AppStore
+    private static func refreshReceipt(receiptProperties: [String: Any]?) -> Result<Data, Error>.Promise {
+        return Result<(), Swift.Error>.Promise { resolver in
+            let operation = ReceiptRefreshOperation(receiptProperties: receiptProperties) { result in
+                resolver.resolve(value: result)
             }
+            self.operationQueue.addOperation(operation)
         }
-    }
-
-    private static func refreshReceipt(receiptProperties: [String: Any]?, completionHandler: @escaping (Result<Data, Error>) -> Void) {
-        let refreshOperation = ReceiptRefreshOperation(receiptProperties: receiptProperties)
-        refreshOperation.addDidFinishBlockObserver { (operation, result) in
-            let result = result
-                .mapError { Error.refresh($0) }
-                .flatMap { Self.readFromDisk() }
-            completionHandler(result)
+        .mapError { error in
+            return .refresh(error)
+        }
+        .flatMap {
+            return Self.readFromDisk()
         }
-
-        operationQueue.addOperation(refreshOperation)
     }
 }
 
-
-private class ReceiptRefreshOperation: AsyncOperation, OutputOperation, SKRequestDelegate {
-    typealias Output = Result<(), Error>
-
-    private let request: SKReceiptRefreshRequest
-
-    init(receiptProperties: [String: Any]?) {
-        request = SKReceiptRefreshRequest(receiptProperties: receiptProperties)
-    }
-
-    override func main() {
-        request.delegate = self
-        request.start()
-    }
-
-    override func operationDidCancel() {
-        request.cancel()
-    }
-
-    // - MARK: SKRequestDelegate
-
-    func requestDidFinish(_ request: SKRequest) {
-        finish(with: .success(()))
-    }
-
-    func request(_ request: SKRequest, didFailWithError error: Error) {
-        finish(with: .failure(error))
-    }
-}
diff --git a/ios/MullvadVPN/Operations/ReceiptRefreshOperation.swift b/ios/MullvadVPN/Operations/ReceiptRefreshOperation.swift
new file mode 100644
index 0000000000..c386fc1cb1
--- /dev/null
+++ b/ios/MullvadVPN/Operations/ReceiptRefreshOperation.swift
@@ -0,0 +1,46 @@
+//
+//  ReceiptRefreshOperation.swift
+//  ReceiptRefreshOperation
+//
+//  Created by pronebird on 02/09/2021.
+//  Copyright © 2021 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+import StoreKit
+
+class ReceiptRefreshOperation: AsyncOperation, SKRequestDelegate {
+    private let request: SKReceiptRefreshRequest
+    private let completionHandler: (Result<(), Error>) -> Void
+
+    init(receiptProperties: [String: Any]?, completionHandler: @escaping (Result<(), Error>) -> Void) {
+        request = SKReceiptRefreshRequest(receiptProperties: receiptProperties)
+        self.completionHandler = completionHandler
+
+        super.init()
+
+        request.delegate = self
+    }
+
+    override func main() {
+        request.start()
+    }
+
+    override func cancel() {
+        super.cancel()
+
+        request.cancel()
+    }
+
+    // - MARK: SKRequestDelegate
+
+    func requestDidFinish(_ request: SKRequest) {
+        completionHandler(.success(()))
+        finish()
+    }
+
+    func request(_ request: SKRequest, didFailWithError error: Error) {
+        completionHandler(.failure(error))
+        finish()
+    }
+}