Add WEB-support for CoreStoreSembastImp (#436)

* Add websupport for CoreStoreSembastImp

* Add debug warning when using sembast on web

ParseCoreData().debug should be null at that time

* fixed issues

Author: fischerscode

README.md

@@ -27,6 +27,8 @@ await Parse().initialize(
 ```
 
 If you want to use secure storage or use the Flutter web/desktop SDK, please change to the below instance of CoreStorage as it has no dependencies on Flutter.
+
+**The `CoreStoreSembastImp` does not encrypt the data!** (Web is not safe anyway. Encrypt fields manually as needed.)
 ```dart
 
 await Parse().initialize(

lib/parse_server_sdk_dart.dart

@@ -14,6 +14,7 @@ import 'package:parse_server_sdk/src/network/parse_websocket.dart'
 import 'package:path/path.dart' as path;
 import 'package:sembast/sembast.dart';
 import 'package:sembast/sembast_io.dart';
+import 'package:sembast_web/sembast_web.dart';
 import 'package:uuid/uuid.dart';
 import 'package:web_socket_channel/web_socket_channel.dart';
 import 'package:xxtea/xxtea.dart';

lib/src/storage/core_store_sem_impl.dart

@@ -9,9 +9,16 @@ class CoreStoreSembastImp implements CoreStore {
   static Future<CoreStore> getInstance(String dbPath,
       {DatabaseFactory factory, String password = 'flutter_sdk'}) async {
     if (_instance == null) {
-      factory ??= databaseFactoryIo;
-      final SembastCodec codec = getXXTeaSembastCodec(password: password);
-      final Database db = await factory.openDatabase(dbPath, codec: codec);
+      factory ??= !parseIsWeb ? databaseFactoryIo : databaseFactoryWeb;
+      assert(() {
+        if (parseIsWeb) {
+          print(
+              'Warning: CoreStoreSembastImp of the Parse_Server_SDK does not encrypt the database on WEB.');
+        }
+        return true;
+      }());
+      final Database db = await factory.openDatabase(dbPath,
+          codec: !parseIsWeb ? getXXTeaSembastCodec(password: password) : null);
       _instance =
           CoreStoreSembastImp._internal(db, StoreRef<String, String>.main());
     }

pubspec.yaml

@@ -17,6 +17,7 @@ dependencies:
 
   #Database
   sembast: ^2.4.7+6
+  sembast_web: '>=1.0.0'
   xxtea: ^2.0.3
   shared_preferences: ^0.5.10 # only used in the flutter part