Merge pull request #73 from qonversion/feature/promoPurchases

Add support for promo purchases on iOS

Author: Maria-Bordunova

android/src/main/kotlin/com/qonversion/flutter/sdk/qonversion_flutter_sdk/BaseListenerWrapper.kt

@@ -3,14 +3,13 @@ package com.qonversion.flutter.sdk.qonversion_flutter_sdk
 import io.flutter.plugin.common.BinaryMessenger
 import io.flutter.plugin.common.EventChannel
 
-abstract class BaseListenerWrapper(
-        val binaryMessenger: BinaryMessenger
+class BaseListenerWrapper internal constructor(
+        private val binaryMessenger: BinaryMessenger,
+        private val eventChannelPostfix: String
 ) {
 
-    protected abstract val eventChannelPostfix: String
-
-    protected var eventChannel: EventChannel? = null
-    protected var eventStreamHandler: BaseEventStreamHandler? = null
+    private var eventChannel: EventChannel? = null
+    var eventStreamHandler: BaseEventStreamHandler? = null
 
     fun register() {
         eventStreamHandler =

android/src/main/kotlin/com/qonversion/flutter/sdk/qonversion_flutter_sdk/QonversionFlutterSdkPlugin.kt

@@ -19,11 +19,10 @@ import com.qonversion.android.sdk.dto.offerings.QOfferings
 import com.qonversion.android.sdk.dto.products.QProduct
 
 /** QonversionFlutterSdkPlugin */
-class QonversionFlutterSdkPlugin internal constructor(registrar: Registrar): MethodCallHandler, BaseListenerWrapper(registrar.messenger()) {
+class QonversionFlutterSdkPlugin internal constructor(registrar: Registrar): MethodCallHandler {
     private val activity: Activity = registrar.activity()
     private val application: Application = activity.application
-
-    override val eventChannelPostfix = "updated_purchases"
+    private var deferredPurchasesStreamHandler: BaseEventStreamHandler? = null
 
     companion object {
         @JvmStatic
@@ -32,8 +31,14 @@ class QonversionFlutterSdkPlugin internal constructor(registrar: Registrar): Met
             val instance = QonversionFlutterSdkPlugin(registrar)
             channel.setMethodCallHandler(instance)
 
-            // Register Updated Purchases Event Channel
-            instance.register()
+            // Register deferred purchases events
+            val purchasesListener = BaseListenerWrapper(registrar.messenger(), "updated_purchases")
+            purchasesListener.register()
+            instance.deferredPurchasesStreamHandler = purchasesListener.eventStreamHandler
+
+            // Register promo purchases events. Android SDK does not generate any promo purchases yet
+            val promoPurchasesListener = BaseListenerWrapper(registrar.messenger(), "promo_purchases")
+            promoPurchasesListener.register()
         }
     }
 
@@ -127,7 +132,7 @@ class QonversionFlutterSdkPlugin internal constructor(registrar: Registrar): Met
             override fun onPermissionsUpdate(permissions: Map<String, QPermission>) {
                 val payload = Gson().toJson(permissions.mapValues { it.value.toMap() })
 
-                eventStreamHandler?.eventSink?.success(payload)
+                deferredPurchasesStreamHandler?.eventSink?.success(payload)
             }
         })
     }

example/lib/products_view.dart

@@ -11,21 +11,42 @@ class ProductsView extends StatefulWidget {
 class _ProductsViewState extends State<ProductsView> {
   var _products = <String, QProduct>{};
   QOfferings _offerings;
-  StreamSubscription<Map<String, QPermission>> _subscription;
+  StreamSubscription<Map<String, QPermission>> _deferredPurchasesStream;
+  StreamSubscription<String> _promoPurchasesStream;
 
   @override
   void initState() {
     super.initState();
     _loadProducts();
     _loadOfferings();
 
-    _subscription =
+    _deferredPurchasesStream =
         Qonversion.updatedPurchasesStream.listen((event) => print(event));
+
+    _promoPurchasesStream =
+        Qonversion.promoPurchasesStream.listen((promoPurchaseId) async {
+      try {
+        final permissions = await Qonversion.promoPurchase(promoPurchaseId);
+        // Get Qonversion product by App Store ID
+        final qProduct = _products.values.firstWhere(
+            (element) => element.storeId == promoPurchaseId,
+            orElse: () => null);
+        // Get permission by Qonversion product
+        final permission = permissions.values.firstWhere(
+            (element) => element.productId == qProduct?.qonversionId,
+            orElse: () => null);
+
+        print(permission?.isActive);
+      } catch (e) {
+        print(e);
+      }
+    });
   }
 
   @override
   void dispose() {
-    _subscription.cancel();
+    _deferredPurchasesStream.cancel();
+    _promoPurchasesStream.cancel();
 
     super.dispose();
   }
@@ -108,8 +129,12 @@ class _ProductsViewState extends State<ProductsView> {
             color: Colors.blue,
             textColor: Colors.white,
             onPressed: () async {
-              final res = await Qonversion.purchase(product.qonversionId);
-              print(res[product.qonversionId]?.isActive);
+              final permissions = await Qonversion.purchase(product.qonversionId);
+              final permission =  permissions.values.firstWhere(
+                      (element) => element.productId == product.qonversionId,
+                  orElse: () => null);
+
+              print(permission?.isActive);
             },
           ),
         ),

ios/Classes/FlutterError+Custom.swift

@@ -77,4 +77,10 @@ extension FlutterError {
   static let noSdkInfo = FlutterError(code: "15",
                                       message: "Could not find sdk info",
                                       details: passValidValue)
+  
+  static func promoPurchaseError(_ productId: String) -> FlutterError {
+    return FlutterError (code: "PromoPurchase",
+                         message: "Could not find completion block for Product ID: \(productId)",
+                         details: passValidValue)
+  }
 }

ios/Classes/SwiftQonversionFlutterSdkPlugin.swift

@@ -7,7 +7,9 @@ import Flutter
 import Qonversion
 
 public class SwiftQonversionFlutterSdkPlugin: NSObject, FlutterPlugin {
-  var purchasesEventStreamHandler: BaseEventStreamHandler?
+  var deferredPurchasesStreamHandler: BaseEventStreamHandler?
+  var promoPurchasesStreamHandler: BaseEventStreamHandler?
+  var promoPurchasesExecutionBlocks = [String: Qonversion.PromoPurchaseCompletionHandler]()
 
   public static func register(with registrar: FlutterPluginRegistrar) {
     let messenger: FlutterBinaryMessenger
@@ -20,12 +22,15 @@ public class SwiftQonversionFlutterSdkPlugin: NSObject, FlutterPlugin {
     let instance = SwiftQonversionFlutterSdkPlugin()
     registrar.addMethodCallDelegate(instance, channel: channel)
 
-    // Register events listeners
+    // Register deferred purchases events
     let purchasesListener = FlutterListenerWrapper<BaseEventStreamHandler>(registrar, postfix: "updated_purchases")
-    purchasesListener.register() { instance.purchasesEventStreamHandler = $0 }
-    
-    // Setting delegate as soon as plugin is registered
+    purchasesListener.register() { instance.deferredPurchasesStreamHandler = $0 }
     Qonversion.setPurchasesDelegate(instance)
+    
+    // Register promo purchases events
+    let promoPurchasesListener = FlutterListenerWrapper<BaseEventStreamHandler>(registrar, postfix: "promo_purchases")
+    promoPurchasesListener.register() { instance.promoPurchasesStreamHandler = $0 }
+    Qonversion.setPromoPurchasesDelegate(instance)
   }
 
   public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
@@ -78,6 +83,9 @@ public class SwiftQonversionFlutterSdkPlugin: NSObject, FlutterPlugin {
     case "purchase":
       return purchase(args["productId"] as? String, result)
 
+    case "promoPurchase":
+      return promoPurchase(args["productId"] as? String, result)
+      
     case "setUserId":
       return setUserId(args["userId"] as? String, result)
 
@@ -154,6 +162,25 @@ public class SwiftQonversionFlutterSdkPlugin: NSObject, FlutterPlugin {
     }
   }
 
+  private func promoPurchase(_ productId: String?, _ result: @escaping FlutterResult) {
+    guard let productId = productId else {
+      return result(FlutterError.noProductId)
+    }
+    
+    if let executionBlock = promoPurchasesExecutionBlocks[productId] {
+      promoPurchasesExecutionBlocks.removeValue(forKey: productId)
+      
+      executionBlock { (permissions, error, isCancelled) in
+        let purchaseResult = PurchaseResult(permissions: permissions,
+                                            error: error,
+                                            isCancelled: isCancelled)
+        result(purchaseResult.toMap())
+      }
+    } else {
+      result(FlutterError.promoPurchaseError(productId))
+    }
+  }
+  
   private func checkPermissions(_ result: @escaping FlutterResult) {
     Qonversion.checkPermissions { (permissions, error) in
       if let error = error {
@@ -295,6 +322,14 @@ extension SwiftQonversionFlutterSdkPlugin: Qonversion.PurchasesDelegate {
   public func qonversionDidReceiveUpdatedPermissions(_ permissions: [String : Qonversion.Permission]) {
     let payload = permissions.mapValues { $0.toMap() }.toJson()
 
-    purchasesEventStreamHandler?.eventSink?(payload)
+    deferredPurchasesStreamHandler?.eventSink?(payload)
+  }
+}
+
+extension SwiftQonversionFlutterSdkPlugin: QNPromoPurchasesDelegate {
+  public func shouldPurchasePromoProduct(withIdentifier productID: String, executionBlock: @escaping Qonversion.PromoPurchaseCompletionHandler) {
+    promoPurchasesExecutionBlocks[productID] = executionBlock
+    
+    promoPurchasesStreamHandler?.eventSink?(productID)
   }
 }

lib/src/constants.dart

@@ -20,6 +20,7 @@ class Constants {
   static const mLaunch = 'launch';
   static const mProducts = 'products';
   static const mPurchase = 'purchase';
+  static const mPromoPurchase = 'promoPurchase';
   static const mUpdatePurchase = 'updatePurchase';
   static const mCheckPermissions = 'checkPermissions';
   static const mRestore = 'restore';

lib/src/qonversion.dart

@@ -19,9 +19,13 @@ class Qonversion {
   static const String _sdkVersion = "3.0.1";
 
   static const MethodChannel _channel = MethodChannel('qonversion_flutter_sdk');
+
   static const _purchasesEventChannel =
       EventChannel('qonversion_flutter_updated_purchases');
 
+  static const _promoPurchasesEventChannel =
+      EventChannel('qonversion_flutter_promo_purchases');
+
   /// Yields an event each time a deferred transaction happens
   static Stream<Map<String, QPermission>> get updatedPurchasesStream =>
       _purchasesEventChannel
@@ -34,6 +38,12 @@ class Qonversion {
             .map((key, value) => MapEntry(key, QPermission.fromJson(value)));
       });
 
+  /// Yields an event each time a promo transaction happens on iOS.
+  /// Returns App Store product ID
+  static Stream<String> get promoPurchasesStream => _promoPurchasesEventChannel
+          .receiveBroadcastStream()
+          .cast<String>();
+
   /// Initializes Qonversion SDK with the given API key.
   /// You can get one in your account on qonversion.io.
   static Future<QLaunchResult> launch(
@@ -94,17 +104,7 @@ class Qonversion {
     final rawResult = await _channel
         .invokeMethod(Constants.mPurchase, {Constants.kProductId: productId});
 
-    final resultMap = Map<String, dynamic>.from(rawResult);
-
-    final error = resultMap[Constants.kError];
-    if (error != null) {
-      throw QPurchaseException(
-        error,
-        isUserCancelled: resultMap[Constants.kIsCancelled] ?? false,
-      );
-    }
-
-    return QMapper.permissionsFromJson(resultMap[Constants.kPermissions]);
+    return _handlePurchaseResult(rawResult);
   }
 
   /// Android only. Returns `null` if called on iOS.
@@ -130,6 +130,22 @@ class Qonversion {
     return QMapper.permissionsFromJson(rawResult);
   }
 
+  /// iOS only. Returns `null` if called on Android.
+  /// Starts a promo purchase process with App Store [productId].
+  ///
+  /// Throws `QPurchaseException` in case of error in purchase flow.
+  static Future<Map<String, QPermission>?> promoPurchase(
+      String productId) async {
+    if (!Platform.isIOS) {
+      return null;
+    }
+
+    final rawResult = await _channel.invokeMethod(
+        Constants.mPromoPurchase, {Constants.kProductId: productId});
+
+    return _handlePurchaseResult(rawResult);
+  }
+
   /// You need to call the checkPermissions method at the start of your app to check if a user has the required permission.
   ///
   /// This method will check the user receipt and will return the current permissions.
@@ -244,4 +260,19 @@ class Qonversion {
         "source": "flutter",
         "sourceKey": Constants.sourceKey
       });
+
+  static Map<String, QPermission> _handlePurchaseResult(
+      Map<dynamic, dynamic> rawResult) {
+    final resultMap = Map<String, dynamic>.from(rawResult);
+
+    final error = resultMap[Constants.kError];
+    if (error != null) {
+      throw QPurchaseException(
+        error,
+        isUserCancelled: resultMap[Constants.kIsCancelled] ?? false,
+      );
+    }
+
+    return QMapper.permissionsFromJson(resultMap[Constants.kPermissions]);
+  }
 }

pubspec.lock

@@ -21,7 +21,7 @@ packages:
       name: args
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0"
+    version: "2.1.0"
   async:
     dependency: transitive
     description:
@@ -91,7 +91,7 @@ packages:
       name: built_value
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "8.0.5"
+    version: "8.0.6"
   characters:
     dependency: transitive
     description:
@@ -161,7 +161,7 @@ packages:
       name: dart_style
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0"
+    version: "2.0.1"
   fake_async:
     dependency: transitive
     description:
@@ -325,7 +325,7 @@ packages:
       name: shelf
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.1.4"
   shelf_web_socket:
     dependency: transitive
     description:
@@ -428,7 +428,7 @@ packages:
       name: web_socket_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0"
+    version: "2.1.0"
   yaml:
     dependency: transitive
     description: