add httpClient with retry

Author: AlexanderThiele

packages/linkfive_purchases/lib/client/linkfive_client.dart

@@ -2,7 +2,7 @@ import 'dart:convert';
 import 'dart:io';
 import 'dart:ui';
 
-import 'package:http/http.dart' as http;
+import 'package:http/http.dart';
 import 'package:in_app_purchase_android/in_app_purchase_android.dart';
 import 'package:in_app_purchase_storekit/in_app_purchase_storekit.dart';
 import 'package:linkfive_purchases/client/linkfive_client_interface.dart';
@@ -11,11 +11,15 @@ import 'package:linkfive_purchases/logic/linkfive_user_management.dart';
 import 'package:linkfive_purchases/models/requests/purchase_request_google.dart';
 import 'package:linkfive_purchases/models/requests/purchase_request_google_otp.dart';
 import 'package:linkfive_purchases/models/requests/purchase_request_pricing_phase.dart';
+import 'package:linkfive_purchases/src/client/http/http_client.dart';
+import 'package:linkfive_purchases/src/client/http/retry_http_client.dart';
 import 'package:linkfive_purchases/store/linkfive_app_data_store.dart';
 import 'package:package_info_plus/package_info_plus.dart';
 
 /// HTTP client to LinkFive
 class LinkFiveClient extends LinkFiveClientInterface {
+  late final httpClient = RetryHttpClient(HttpClientFactory.basic());
+
   final String stagingUrl = "api.staging.linkfive.io";
   final String prodUrl = "api.linkfive.io";
 
@@ -79,7 +83,7 @@ class LinkFiveClient extends LinkFiveClientInterface {
   Future<LinkFiveResponseData> fetchLinkFiveResponse() async {
     final uri = _makeUri("api/v1/subscriptions");
 
-    final response = await http.get(uri, headers: await _headers);
+    final response = await httpClient.get(uri, headers: await _headers);
     LinkFiveLogger.d('Response status: ${response.statusCode}');
     LinkFiveLogger.d('Response body: ${response.body}');
     final mapBody = jsonDecode(response.body);
@@ -107,18 +111,9 @@ class LinkFiveClient extends LinkFiveClientInterface {
     };
 
     LinkFiveLogger.d("purchase. $body");
-    try {
-      final response = await http.post(uri, body: jsonEncode(body), headers: await _headers);
-
-      return _parseOneTimePurchaseListResponse(response);
-    } catch (e) {
-      LinkFiveLogger.e("Purchase Request Error: ${e.toString()}");
-      LinkFiveLogger.e("Try Again with same request");
+    final response = await httpClient.post(uri, body: body, headers: await _headers);
 
-      final response = await http.post(uri, body: jsonEncode(body), headers: await _headers);
-
-      return _parseOneTimePurchaseListResponse(response);
-    }
+    return _parseOneTimePurchaseListResponse(response);
   }
 
   /// after a purchase on Google we call the purchases/google
@@ -151,18 +146,10 @@ class LinkFiveClient extends LinkFiveClientInterface {
 
     LinkFiveLogger.d("purchase: $purchaseBody");
 
-    try {
-      final response = await http.post(uri, body: jsonEncode(purchaseBody.toJson()), headers: await _headers);
-
-      return _parseOneTimePurchaseListResponse(response);
-    } catch (e) {
-      LinkFiveLogger.e("Purchase Request Error: ${e.toString()}");
-      LinkFiveLogger.e("Try Again with same request");
-
-      final response = await http.post(uri, body: jsonEncode(purchaseBody.toJson()), headers: await _headers);
+    final response =
+        await httpClient.post(uri, body: purchaseBody.toJson(), headers: await _headers);
 
-      return _parseOneTimePurchaseListResponse(response);
-    }
+    return _parseOneTimePurchaseListResponse(response);
   }
 
   @override
@@ -178,18 +165,10 @@ class LinkFiveClient extends LinkFiveClientInterface {
     );
 
     LinkFiveLogger.d("purchase: $purchaseBody");
-    try {
-      final response = await http.post(uri, body: jsonEncode(purchaseBody.toJson()), headers: await _headers);
-
-      return _parseOneTimePurchaseListResponse(response);
-    } catch (e) {
-      LinkFiveLogger.e("Purchase Request Error: ${e.toString()}");
-      LinkFiveLogger.e("Try Again with same request");
+    final response =
+        await httpClient.post(uri, body: purchaseBody.toJson(), headers: await _headers);
 
-      final response = await http.post(uri, body: jsonEncode(purchaseBody.toJson()), headers: await _headers);
-
-      return _parseOneTimePurchaseListResponse(response);
-    }
+    return _parseOneTimePurchaseListResponse(response);
   }
 
   /// Fetches the receipts for a user
@@ -200,7 +179,7 @@ class LinkFiveClient extends LinkFiveClientInterface {
   Future<LinkFiveActiveProducts> fetchUserPlanListFromLinkFive() async {
     final uri = _makeUri("api/v1/purchases/user");
 
-    final response = await http.get(uri, headers: await _headers);
+    final response = await httpClient.get(uri, headers: await _headers);
     return _parseOneTimePurchaseListResponse(response);
   }
 
@@ -221,7 +200,7 @@ class LinkFiveClient extends LinkFiveClientInterface {
 
     LinkFiveLogger.d("Restore body: $body");
 
-    final response = await http.post(uri, body: jsonEncode(body), headers: await _headers);
+    final response = await httpClient.post(uri, body: body, headers: await _headers);
     return _parseOneTimePurchaseListResponse(response);
   }
 
@@ -242,15 +221,15 @@ class LinkFiveClient extends LinkFiveClientInterface {
 
     LinkFiveLogger.d("Restore body: $body");
 
-    final response = await http.post(uri, body: jsonEncode(body), headers: await _headers);
+    final response = await httpClient.post(uri, body: body, headers: await _headers);
     return _parseOneTimePurchaseListResponse(response);
   }
 
   @override
   Future<LinkFiveActiveProducts> changeUserId(String? userId) async {
     final uri = _makeUri("api/v1/purchases/user/customer-user-id");
 
-    final response = await http.put(uri, headers: await _headers);
+    final response = await httpClient.put(uri, headers: await _headers);
     return _parseOneTimePurchaseListResponse(response);
   }
 
@@ -263,7 +242,7 @@ class LinkFiveClient extends LinkFiveClientInterface {
     return Uri.https(hostUrl, path, queryParams);
   }
 
-  LinkFiveActiveProducts _parseOneTimePurchaseListResponse(http.Response response) {
+  LinkFiveActiveProducts _parseOneTimePurchaseListResponse(Response response) {
     LinkFiveLogger.d("Parse with body ${response.body}");
 
     Map<String, dynamic> jsonResponse = jsonDecode(response.body);

packages/linkfive_purchases/lib/logic/linkfive_purchases_impl.dart

@@ -61,8 +61,8 @@ class LinkFivePurchasesImpl extends DefaultPurchaseHandler implements CallbackIn
 
   //#region Members
 
-  /// Cache of AppStoreProductDetail
-  ProductDetails? _productDetailsToPurchase;
+  /// Saving productDetails for the purchase
+  ProductDetails? _lastProductDetailsToPurchase;
 
   /// the v2 of purchases waits for the async purchase response and completes the future
   final List<Completer<LinkFiveActiveProducts>> registeredPurchaseCompleterList = [];
@@ -238,7 +238,7 @@ class LinkFivePurchasesImpl extends DefaultPurchaseHandler implements CallbackIn
 
     // We're saving the product Details whenever the user purchases a product to send it to the server
     // after a purchase
-    _productDetailsToPurchase = productDetailsProcessed;
+    _lastProductDetailsToPurchase = productDetailsProcessed;
 
     try {
       // try to buy it
@@ -465,22 +465,19 @@ class LinkFivePurchasesImpl extends DefaultPurchaseHandler implements CallbackIn
           super.isPendingPurchase = false;
           break;
         case PurchaseStatus.purchased:
-          final productDetails = _productDetailsToPurchase;
-          _productDetailsToPurchase = null;
-
           // handle ios Purchase
           if (Platform.isIOS) {
             // handle the ios purchase request to LinkFive
             await _handlePurchaseApple(
               appstorePurchaseDetails: purchaseDetails as AppStorePurchaseDetails,
-              productDetailsToPurchase: productDetails,
+              productDetailsToPurchase: _lastProductDetailsToPurchase,
             );
           }
           // Handle google play purchase
           if (purchaseDetails is GooglePlayPurchaseDetails) {
             await _handlePurchaseGoogle(
               purchaseDetails: purchaseDetails,
-              productDetails: productDetails as GooglePlayProductDetails,
+              productDetails: _lastProductDetailsToPurchase as GooglePlayProductDetails,
             );
           }
 

packages/linkfive_purchases/lib/src/client/http/http_client.dart

@@ -0,0 +1,20 @@
+import 'dart:convert';
+
+import 'package:http/http.dart';
+import 'package:http/io_client.dart';
+
+abstract class LinkFiveHttpClient {
+  Future<Response> post(Uri uri, {Map<String, String>? headers, Map<String, dynamic>? body});
+
+  Future<Response> get(Uri url, {Map<String, String>? headers});
+
+  Future<Response> put(Uri url, {Map<String, String>? headers, Map<String, dynamic>? body, Encoding? encoding});
+}
+
+class HttpClientFactory {
+  final Client _client;
+
+  HttpClientFactory.basic() : _client = IOClient();
+
+  Client getClient() => _client;
+}

packages/linkfive_purchases/lib/src/client/http/retry_http_client.dart

@@ -0,0 +1,57 @@
+import 'dart:convert';
+
+import 'package:http/http.dart' as http;
+import 'package:in_app_purchases_interface/in_app_purchases_interface.dart';
+import 'package:linkfive_purchases/src/client/http/http_client.dart';
+
+/// HTTP Client with retry function
+class RetryHttpClient extends LinkFiveHttpClient {
+  final http.Client httpClient;
+  final int requestTimeoutSeconds;
+  final int retryTimeoutMillis;
+  final int retryTimes = 3;
+
+  RetryHttpClient(HttpClientFactory clientFactory)
+      : httpClient = clientFactory.getClient(),
+        requestTimeoutSeconds = 16,
+        retryTimeoutMillis = 500;
+
+  RetryHttpClient.test(HttpClientFactory clientFactory)
+      : httpClient = clientFactory.getClient(),
+        requestTimeoutSeconds = 1,
+        retryTimeoutMillis = 0;
+
+  @override
+  Future<http.Response> post(Uri uri, {Map<String, String>? headers, Map<String, dynamic>? body}) async {
+    for (int retryCount = 0; retryCount < retryTimes; retryCount++) {
+      try {
+        final response = await httpClient
+            .post(uri, body: jsonEncode(body), headers: headers)
+            .timeout(Duration(seconds: requestTimeoutSeconds));
+        if(response.statusCode == 429){
+          throw Exception("Too many requests");
+        }
+        return response;
+      } catch (e) {
+        if (retryCount >= retryTimes - 1) {
+          LinkFiveLogger.e("Retried $retryCount but still Request Error: ${e.toString()}");
+          rethrow;
+        }
+        LinkFiveLogger.e("Purchase Request Error: ${e.toString()}");
+        LinkFiveLogger.e("Try Again with same request");
+        await Future.delayed(Duration(milliseconds: retryTimeoutMillis));
+      }
+    }
+    throw Exception("Could not do any request");
+  }
+
+  @override
+  Future<http.Response> get(Uri url, {Map<String, String>? headers}) {
+    return httpClient.get(url, headers: headers);
+  }
+
+  @override
+  Future<http.Response> put(Uri url, {Map<String, String>? headers, Object? body, Encoding? encoding}) {
+    return httpClient.put(url, headers: headers, body: body, encoding: encoding);
+  }
+}

packages/linkfive_purchases/pubspec.yaml

@@ -28,6 +28,7 @@ dev_dependencies:
   test: ^1.25.1
   flutter_lints: ^3.0.1
   mockito: ^5.4.4
+  mocktail: ^1.0.3
   build_runner: ^2.4.8
   json_serializable: ^6.7.1
 

packages/linkfive_purchases/test/src/client/http/retry_http_client_test.dart

@@ -0,0 +1,115 @@
+import 'dart:async';
+
+import 'package:http/src/response.dart';
+import 'package:linkfive_purchases/src/client/http/retry_http_client.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:test/test.dart';
+
+import '../mocks.dart';
+
+void main() {
+  final uri = Uri.parse("linkfive.io");
+
+  setUpAll(() {
+    registerFallbackValue(Uri());
+  });
+
+  test('instant 200', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async => Response("", 200));
+
+    final Response response = await retryClient.post(uri);
+
+    expect(response.statusCode, 200);
+  });
+
+  test('always Exception', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenThrow(Error());
+
+    expect(retryClient.post(uri), throwsA(isA<Error>()));
+  });
+
+  test('retry after 1', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    int requestCounter = 0;
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      if (requestCounter++ < 1) {
+        throw Exception("");
+      }
+      return Response("", 200);
+    });
+
+    final Response response = await retryClient.post(uri);
+
+    expect(response.statusCode, 200);
+  });
+
+  test('retry max RetryTimes + 0', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    int requestCounter = 0;
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      if (requestCounter++ < retryClient.retryTimes - 1) {
+        throw Error();
+      }
+      return Response("", 200);
+    });
+
+    final Response response = await retryClient.post(uri);
+
+    expect(response.statusCode, 200);
+  });
+
+  test('retry max RetryTimes + 1 error', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    int requestCounter = 0;
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      if (requestCounter++ < retryClient.retryTimes) {
+        throw Error();
+      }
+      return Response("", 200);
+    });
+    expect(retryClient.post(uri), throwsA(isA<Error>()));
+  });
+
+  test('test timeout', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      await Future.delayed(const Duration(seconds: 15));
+      return Response("", 200);
+    });
+    expect(retryClient.post(uri), throwsA(isA<TimeoutException>()));
+  });
+
+  test('test error too many requests', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      return Response("", 429);
+    });
+    expect(retryClient.post(uri), throwsA(isA<Exception>()));
+  });
+
+  test('test success with -1 too many requests', () async {
+    final mockClient = MockClient();
+    final retryClient = RetryHttpClient.test(MockHttpClientFactory()..withMockClient(mockClient));
+    int requestCounter = 0;
+    when(() => mockClient.post(any(), body: any(named: "body"))).thenAnswer((_) async {
+      if (requestCounter++ < retryClient.retryTimes - 1) {
+        return Response("", 429);
+      }
+      return Response("", 200);
+    });
+
+    final response = await retryClient.post(uri);
+    expect(response.statusCode, 200);
+  });
+}