Improvement:

- Shorten log when changing avatar

.dockerignore

@@ -0,0 +1,14 @@
+# Files and directories created by pub.
+Dockerfile
+build/
+.dart_tool/
+.git/
+.github/
+.gitignore
+.packages
+
+.data/
+.tmp/
+
+# Conventional directory for build output.
+build/

Dockerfile

@@ -0,0 +1,27 @@
+# Specify the Dart SDK base image version using dart:<version> (ex: dart:2.12)
+FROM dart:stable AS compile
+
+# Resolve app dependencies.
+WORKDIR /lchatserver
+COPY pubspec.* ./
+RUN dart pub get
+
+# Copy app source code and AOT compile it.
+COPY . .
+# Ensure packages are still up-to-date if anything has changed
+RUN dart pub get --offline
+RUN dart compile exe bin/tcp_server.dart -o bin/tcp_server
+
+FROM ubuntu:latest
+
+RUN apt-get update && apt-get -y install libsqlite3-0 libsqlite3-dev
+
+# Copy the previously built executable into the scratch layer
+RUN mkdir /lchatserver
+COPY --from=compile /runtime/ /lchatserver/
+COPY --from=compile /lchatserver/bin/tcp_server /lchatserver/bin/
+
+# Start server.
+EXPOSE 20706
+WORKDIR /lchatserver/bin
+CMD ["/lchatserver/bin/tcp_server"]

bin/tcp_server.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-06 15:44:16
- * @LastEditTime : 2022-10-09 22:57:10
+ * @LastEditTime : 2022-10-23 10:33:58
  * @Description  : 
  */
 
@@ -15,153 +15,348 @@ import 'package:tcp_server/tcpcontroller/request.dart';
 import 'package:tcp_server/tcpcontroller/response.dart';
 
 void main(List<String> arguments) async {
-  //Set port
+  //Set address
   var port = arguments.isEmpty ? 20706 : int.tryParse(arguments[0]) ?? 20706;
 
+  print('[L] [STARTUP  ]-----------------------');
+  print('[L] Running at directory ${Directory.current.path}');
+  
   //Create nessesary working directories
-  await Directory('${Directory.current.path}/.tmp').create();
   await Directory('${Directory.current.path}/.data').create();
+  await Directory('${Directory.current.path}/.data/.tmp').create();
   await Directory('${Directory.current.path}/.data/files').create();
 
   await DataBaseHelper().initialize();
-  var tokenMap = <int, TCPController>{};
-  var controllerMap = <TCPController, Future<int>>{};
-  var listenSocket = await ServerSocket.bind('127.0.0.1', port);
+  Map<int, List<TCPController>> tokenMap = {};
+  Map<TCPController, Future<int>> controllerMap = {};
+  var listenSocket = await ServerSocket.bind(InternetAddress.anyIPv4, port);
   listenSocket.listen(
     (socket) {
       var controller = TCPController(socket: socket);
-      controller.inStream.listen((request) async {
-        print('[L] ${request.toJSON}');
-        if(request.tokenID == null) {
-          if(controllerMap[controller] == null) {
-            controllerMap[controller] = (() async => (await DataBaseHelper().createToken()))();
+      controller.responseStreamBroadcast.listen(
+        null,
+        onError: (_) {
+          print('[L] [EXCEPTION]-----------------------');
+          print('[L] TCP Controller ran into exception');
+          print('[L] socket: ${controller.socket.address}:${controller.socket.port}');
+          var token = controllerMap[controller];
+          controllerMap.remove(controller);
+          tokenMap[token]?.remove(controller);
+        },
+        onDone: () {
+          var token = controllerMap[controller];
+          controllerMap.remove(controller);
+          tokenMap[token]?.remove(controller);
+        },
+        cancelOnError: true
+      );
+      controller.requestStreamBroadcast.listen(
+        (request) async {
+          print('[L] [INCOMING ]-----------------------');
+          print('[L] Incoming from ${controller.socket.remoteAddress}:${controller.socket.remotePort}');
+          if(request.requestType == RequestType.sendMessage) {
+            print('[L] Message: (Message body)');
           }
-          request.tokenID = await controllerMap[controller];
-          var tokenResponse = TCPResponse(
-            type: ResponseType.token,
-            status: ResponseStatus.ok,
-            body: {
-              "tokenid": request.tokenID
+          else if(request.requestType == RequestType.modifyProfile) {
+            print('[L] Profile: (Profile body)');
+          }
+          else {
+            print('[L] Message: ${request.toJSON}');
+          }
+          if(!(await DataBaseHelper().isTokenValid(tokenid: request.tokenID))) {
+            if(controllerMap[controller] == null) {
+              controllerMap[controller] = (() async => (await DataBaseHelper().createToken()))();
             }
-          );
-          controller.outStream.add(tokenResponse);
-        }
-        tokenMap[request.tokenID!] = tokenMap[request.tokenID!] ?? controller;
-        switch(request.requestType) {
-          case RequestType.checkState: {
-            var response = await onCheckState(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.register: {
-            var response = await onRegister(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.login: {
-            var response = await onLogin(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.logout: {
-            var response = await onLogout(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.profile: {
-            var response = await onFetchProfile(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.modifyProfile: {
-            var response = await onModifyProfile(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.modifyPassword: {
-            var response = await onModifyPassword(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.sendMessage: {
-            //Forword Message
-            var message = Message.fromJSONObject(request.body);
-            await DataBaseHelper().setFetchHistoryFor(
-              tokenID: request.tokenID, 
-              newTimeStamp: message.timestamp
-            );
-            var originUserID = message.senderID;
-            var onlineDevices = await DataBaseHelper().fetchTokenIDsViaUserID(userID: originUserID);
-            for(var device in onlineDevices) {
-              if(device == request.tokenID) {
-                continue;
+            request.tokenID = await controllerMap[controller];
+            var tokenResponse = TCPResponse(
+              type: ResponseType.token,
+              status: ResponseStatus.ok,
+              body: {
+                "tokenid": request.tokenID
               }
-              var targetController = tokenMap[device];
-              var forwardResponse = TCPResponse(
-                type: ResponseType.forwardMessage,
-                status: ResponseStatus.ok,
-                body: message.jsonObject
-              );
-              targetController?.outStream.add(forwardResponse);
-              //Update Fetch Histories
+            );
+            controller.outStream.add(tokenResponse);
+          }
+          tokenMap[request.tokenID!] ??= [];
+          if(!tokenMap[request.tokenID]!.contains(controller)) {
+            tokenMap[request.tokenID]!.add(controller);
+          }
+          switch(request.requestType) {
+            case RequestType.checkState: {
+              var response = await onCheckState(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.register: {
+              var response = await onRegister(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.login: {
+              var response = await onLogin(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.logout: {
+              var response = await onLogout(request, socket);
+              controller.outStream.add(response);
+              break;
+            }
+            case RequestType.profile: {
+              var response = await onFetchProfile(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.modifyProfile: {
+              var response = await onModifyProfile(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.modifyPassword: {
+              var response = await onModifyPassword(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.sendMessage: {
+              //Forword Message
+              var message = Message.fromJSONObject(request.body);
               await DataBaseHelper().setFetchHistoryFor(
-                tokenID: device, 
+                tokenID: request.tokenID, 
                 newTimeStamp: message.timestamp
               );
+              var originUserID = message.senderID;
+              var onlineDevices = await DataBaseHelper().fetchTokenIDsViaUserID(userID: originUserID);
+              for(var device in onlineDevices) {
+                if(device == request.tokenID) {
+                  continue;
+                }
+                var targetControllers = tokenMap[device] ?? [];
+                var forwardResponse = TCPResponse(
+                  type: ResponseType.forwardMessage,
+                  status: ResponseStatus.ok,
+                  body: message.jsonObject
+                );
+                for(var controller in targetControllers) {
+                  try {
+                    print('[L] [MSGFOWARD]-----------------------');
+                    print('[L] Forwarding message to ${controller.socket.remoteAddress}:${controller.socket.remotePort}');
+                    controller.outStream.add(forwardResponse);
+                  } catch(e) {
+                    print('[E] [EXCEPTION]-----------------------');
+                    var token = controllerMap[controller];
+                    controllerMap.remove(controller);
+                    tokenMap[token]?.remove(controller);
+                    continue;
+                  }
+                }
+                // //Update Fetch Histories
+                // await DataBaseHelper().setFetchHistoryFor(
+                //   tokenID: device, 
+                //   newTimeStamp: message.timestamp
+                // );
+              }
+              var targetUserID = message.receiverID;
+              var targetDevices = await DataBaseHelper().fetchTokenIDsViaUserID(userID: targetUserID);
+              for(var device in targetDevices) {
+                //Forward to socket
+                var targetControllers = tokenMap[device] ?? [];
+                var forwardResponse = TCPResponse(
+                  type: ResponseType.forwardMessage,
+                  status: ResponseStatus.ok,
+                  body: message.jsonObject
+                );
+                for(int i = targetControllers.length - 1; i >= 0; i--) {
+                  var controller = targetControllers[i];
+                  try{
+                    print('[L] [MSGFOWARD]-----------------------');
+                    print('[L] Forwarding message to ${controller.socket.remoteAddress}:${controller.socket.remotePort}');
+                    controller.outStream.add(forwardResponse);
+                  } catch(e) {
+                    print('[E] [EXCEPTION]-----------------------');
+                    var token = controllerMap[controller];
+                    controllerMap.remove(controller);
+                    tokenMap[token]?.remove(controller);
+                    continue;
+                  }
+                }
+                // //Update Fetch Histories
+                // await DataBaseHelper().setFetchHistoryFor(
+                //   tokenID: device, 
+                //   newTimeStamp: message.timestamp
+                // );
+              }
+              var response = await onSendMessage(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
             }
-            var targetUserID = message.receiverID;
-            var targetDevices = await DataBaseHelper().fetchTokenIDsViaUserID(userID: targetUserID);
-            for(var device in targetDevices) {
-              //Forward to socket
-              var targetController = tokenMap[device];
-              var forwardResponse = TCPResponse(
-                type: ResponseType.forwardMessage,
-                status: ResponseStatus.ok,
-                body: message.jsonObject
-              );
-              targetController?.outStream.add(forwardResponse);
-              //Update Fetch Histories
-              await DataBaseHelper().setFetchHistoryFor(
-                tokenID: device, 
-                newTimeStamp: message.timestamp
-              );
+            case RequestType.fetchMessage: {
+              var response = await onFetchMessage(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.findFile: {
+              var response = await onFindFile(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.fetchFile: {
+              var response = await onFetchFile(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.searchUser: {
+              var response = await onSearchUser(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.addContact: {
+              var response = await onAddContact(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              var contactResponse = await onFetchContact(
+                TCPRequest.fromData(
+                  type: RequestType.fetchContact, 
+                  body: {}, 
+                  tokenID: request.tokenID
+                ), 
+                socket
+              );
+              controller.outStream.add(contactResponse);
+              break;
+            }
+            case RequestType.fetchContact: {
+              var response = await onFetchContact(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            case RequestType.ackFetch: {
+              onAckFetch(request, socket);
+              break;
+            }
+            case RequestType.unknown: {
+              var response = await onUnknownRequest(request, socket);
+              try {
+                controller.outStream.add(response);
+              } catch (e) {
+                print('[E] [EXCEPTION]-----------------------');
+                var token = controllerMap[controller];
+                controllerMap.remove(controller);
+                tokenMap[token]?.remove(controller);
+              }
+              break;
+            }
+            default: {
+              print('[E] Drop out of switch case');
             }
-            var response = await onSendMessage(request, socket);
-            controller.outStream.add(response);
-            break;
           }
-          case RequestType.fetchMessage: {
-            var response = await onFetchMessage(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.fetchFile: {
-            var response = await onFetchFile(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.searchUser: {
-            var response = await onSearchUser(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.fetchContact: {
-            var response = await onFetchContact(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          case RequestType.unknown: {
-            var response = await onUnknownRequest(request, socket);
-            controller.outStream.add(response);
-            break;
-          }
-          default: {
-            print('[E] Drop out of switch case');
+          //Clear temp file
+          if(request.payload?.existsSync() ?? false) {
+            request.payload?.delete();
           }
+        },
+        onError: (e) {
+          print(e);
+          var token = controllerMap[controller];
+          controllerMap.remove(controller);
+          tokenMap[token]?.remove(controller);
+        },
+        onDone: () {
+          var token = controllerMap[controller];
+          controllerMap.remove(controller);
+          tokenMap[token]?.remove(controller);
         }
-        //Clear temp file
-        request.payload?.delete();
-      });
+      );
     },
+    cancelOnError: true
   );
 }

lib/database.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-06 16:15:01
- * @LastEditTime : 2022-10-09 20:31:23
+ * @LastEditTime : 2022-10-22 21:08:27
  * @Description  : 
  */
 
@@ -25,7 +25,7 @@ class DataBaseHelper {
 
   Future<void> initialize() async {
     _database = await databaseFactoryFfi.openDatabase(
-      '${Directory.current.path}/.tmp/database.db',
+      '${Directory.current.path}/.data/.tmp/database.db',
       options: OpenDatabaseOptions(
         version: 1,
         onCreate: (db, version) async {
@@ -34,7 +34,7 @@ class DataBaseHelper {
             '''
               CREATE TABLE users (
                 userid    integer primary key autoincrement,
-                username  text not null,
+                username  text unique not null,
                 passwd    text not null,
                 avatar    text
               );
@@ -83,6 +83,24 @@ class DataBaseHelper {
     );
   }
 
+  Future<bool> isTokenValid({
+    required int? tokenid,
+  }) async {
+    if(tokenid == null) {
+      return false;
+    }
+
+    var tokenQueryResult = await _database.query(
+      'tokens',
+      where: 'tokenid = ?',
+      whereArgs: [
+        tokenid
+      ]
+    );
+
+    return tokenQueryResult.isNotEmpty;
+  }
+
   //Creates new token
   Future<int> createToken() async {
     //Insert new row
@@ -223,17 +241,29 @@ class DataBaseHelper {
     
     //Insert into users
     try {
-      await _database.insert(
-        'users',
-        {
-          'username': identity.userName,
-          'passwd': identity.userPasswd,
-          'avatar': null
-        },
-        conflictAlgorithm: ConflictAlgorithm.rollback
-      );
-    } catch (conflict) {
-      throw Exception(['Database failure', conflict.toString()]);
+      await _database.transaction((txn) async {
+        var result = await txn.query(
+          'users',
+          where: 'username = ?',
+          whereArgs: [
+            identity.userName
+          ]
+        );
+        if(result.isNotEmpty) {
+          throw Exception('Username already exists');
+        }
+        await txn.insert(
+          'users',
+          {
+            'username': identity.userName,
+            'passwd': identity.userPasswd,
+            'avatar': null
+          },
+          conflictAlgorithm: ConflictAlgorithm.rollback
+        );
+      });
+    } catch (e) {
+      rethrow;
     }
 
     //Get new userid
@@ -340,7 +370,16 @@ class DataBaseHelper {
 
     //Fetch unfetched messages
     var unfetchMsgQueryResult = await _database.query(
-      'msgs',
+      'msgs left outer join msgfiles on msgs.md5encoded = msgfiles.msgmd5',
+      columns: [
+        'msgs.userid as userid',
+        'msgs.targetid as targetid',
+        'msgs.contenttype as contenttype',
+        'msgs.content as content',
+        'msgs.timestamp as timestamp',
+        'msgs.md5encoded as md5encoded',
+        'msgfiles.filemd5 as filemd5'
+      ],
       where: '(userid = ? or targetid = ?) and timestamp > ?',
       whereArgs: [
         userID,
@@ -358,24 +397,25 @@ class DataBaseHelper {
         ),
         content: message['content'] as String,
         timestamp: message['timestamp'] as int,
-        md5encoded: message['md5encoded'] as String
+        md5encoded: message['md5encoded'] as String,
+        filemd5: message['filemd5'] as String?
       );
     }).toList();
 
     //Set new fetch history
-    if(unfetchMsgQueryResult.isNotEmpty) {
-      await _database.update(
-        'histories',
-        {
-          'lastfetch': unfetchMsgQueryResult[0]['timestamp']
-        },
-        where: 'tokenid = ? and userid = ?',
-        whereArgs: [
-          tokenID,
-          userID
-        ]
-      );
-    }
+    // if(unfetchMsgQueryResult.isNotEmpty) {
+    //   await _database.update(
+    //     'histories',
+    //     {
+    //       'lastfetch': unfetchMsgQueryResult[0]['timestamp']
+    //     },
+    //     where: 'tokenid = ? and userid = ?',
+    //     whereArgs: [
+    //       tokenID,
+    //       userID
+    //     ]
+    //   );
+    // }
     
     //return result
     return unfetchMessages;
@@ -484,6 +524,16 @@ class DataBaseHelper {
     var filePath = '${Directory.current.path}/.data/files/$fileMd5';
     await tempFile.copy(filePath);
     try {
+      var sameFile = await _database.query(
+        'files',
+        where: 'filemd5 = ?',
+        whereArgs: [
+          fileMd5
+        ]
+      );
+      if(sameFile.isNotEmpty) {
+        return;
+      }
       await _database.insert(
         'files',
         {
@@ -497,12 +547,25 @@ class DataBaseHelper {
     }
   }
 
+  Future<bool> findFile({
+    required String fileMd5
+  }) async {
+    var targetFile = await _database.query(
+      'files',
+      where: 'filemd5 = ?',
+      whereArgs: [
+        fileMd5
+      ]
+    );
+    return targetFile.isNotEmpty;
+  }
+
   Future<String> fetchFilePath({
     required String msgMd5
   }) async {
     var queryResult = await _database.query(
       'msgfiles natural join files',
-      where: 'msgfile.msgmd5 = ?',
+      where: 'msgfiles.msgmd5 = ?',
       whereArgs: [
         msgMd5
       ]
@@ -510,33 +573,30 @@ class DataBaseHelper {
     if(queryResult.isEmpty) {
       throw Exception('File not found');
     }
-    return queryResult[0]['filedir'] as String;
+    return queryResult[0]['dir'] as String;
   }
 
-  Future<UserInfo> fetchUserInfoViaToken({
-    required int? tokenID
+  Future<UserInfo> fetchUserInfoViaID({
+    required int userid
   }) async {
-    if(tokenID == null) {
-      throw Exception('Invalid device token');
-    }
     
     //Find current binded userID
-    var currentUserQueryResult = (await _database.query(
-      'bindings natural join users',
-      where: 'bindings.tokenid = ?',
+    var userQueryResult = (await _database.query(
+      'users',
+      where: 'userid = ?',
       whereArgs: [
-        tokenID
+        userid
       ]
     ));
-    if(currentUserQueryResult.isEmpty) {
-      throw Exception('User not logged in');
+
+    if(userQueryResult.isEmpty) {
+      throw Exception('User not found');
     }
-    var currentUser = currentUserQueryResult[0];
     
     return UserInfo(
-      userID: currentUser['userid'] as int,
-      userName: currentUser['username'] as String,
-      userAvatar: currentUser['avatar'] as String?
+      userID: userQueryResult[0]['userid'] as int,
+      userName: userQueryResult[0]['username'] as String,
+      userAvatar: userQueryResult[0]['avatar'] as String?
     );
   }
 
@@ -569,6 +629,10 @@ class DataBaseHelper {
           'username': userInfo.userName,
           'avatar': userInfo.userAvatar
         },
+        where: 'userid = ?',
+        whereArgs: [
+          currentUserID
+        ],
         conflictAlgorithm: ConflictAlgorithm.rollback
       );
     } catch (conflict) {
@@ -618,13 +682,19 @@ class DataBaseHelper {
     }
     
     //Find current binded userID
-    var currentUserID = (await _database.query(
+    var currentUserIDQueryResult = (await _database.query(
       'bindings',
       where: 'tokenid = ?',
       whereArgs: [
         tokenID
       ]
-    ))[0]['userid'] as int;
+    ));
+    
+    if(currentUserIDQueryResult.isEmpty) {
+      throw Exception('User not logged in');
+    }
+
+    var currentUserID = currentUserIDQueryResult[0]['userid'] as int;
 
     //Fetch all contacts
     var contactsQueryResult = await _database.query(
@@ -655,14 +725,19 @@ class DataBaseHelper {
       throw Exception('Invalid device token');
     }
     
-    //Find current binded userID
-    var currentUserID = (await _database.query(
+    var currentUserIDQueryResult = (await _database.query(
       'bindings',
       where: 'tokenid = ?',
       whereArgs: [
         tokenID
       ]
-    ))[0]['userid'] as int;
+    ));
+    
+    if(currentUserIDQueryResult.isEmpty) {
+      throw Exception('User not logged in');
+    }
+
+    var currentUserID = currentUserIDQueryResult[0]['userid'] as int;
 
     //Fetch pending contacts
     var contactsQueryResult = await _database.query(
@@ -697,13 +772,19 @@ class DataBaseHelper {
     }
     
     //Find current binded userID
-    var currentUserID = (await _database.query(
+    var currentUserIDQueryResult = (await _database.query(
       'bindings',
       where: 'tokenid = ?',
       whereArgs: [
         tokenID
       ]
-    ))[0]['userid'] as int;
+    ));
+    
+    if(currentUserIDQueryResult.isEmpty) {
+      throw Exception('User not logged in');
+    }
+
+    var currentUserID = currentUserIDQueryResult[0]['userid'] as int;
     
         //Fetch pending contacts
     var contactsQueryResult = await _database.query(

lib/requesthandler.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-08 20:52:48
- * @LastEditTime : 2022-10-09 13:39:02
+ * @LastEditTime : 2022-10-22 20:56:15
  * @Description  : 
  */
 
@@ -90,7 +90,7 @@ Future<TCPResponse> onLogout(TCPRequest request, Socket socket) async {
 
 Future<TCPResponse> onFetchProfile(TCPRequest request, Socket socket) async {
   try {
-    var userInfo = await DataBaseHelper().fetchUserInfoViaToken(tokenID: request.tokenID);
+    var userInfo = await DataBaseHelper().fetchUserInfoViaID(userid: request.body['userid'] as int);
     return TCPResponse(
       type: ResponseType.fromRequestType(request.requestType),
       status: ResponseStatus.ok,
@@ -161,12 +161,15 @@ Future<TCPResponse> onSendMessage(TCPRequest request, Socket socket) async {
     return TCPResponse(
       type: ResponseType.fromRequestType(request.requestType),
       status: ResponseStatus.ok,
+      body: {
+        'md5encoded': message.md5encoded
+      }
     );
   } on Exception catch (exception) {
     return TCPResponse(
       type: ResponseType.fromRequestType(request.requestType),
       status: ResponseStatus.err,
-      errInfo: exception.toString()
+      errInfo: exception.toString(),
     );
   }
 }
@@ -190,6 +193,15 @@ Future<TCPResponse> onFetchMessage(TCPRequest request, Socket socket) async {
   }
 }
 
+Future<TCPResponse> onFindFile(TCPRequest request, Socket socket) async {
+  var hasFile = await DataBaseHelper().findFile(fileMd5: request.body['filemd5'] as String);
+  return TCPResponse(
+    type: ResponseType.fromRequestType(request.requestType),
+    status: hasFile ? ResponseStatus.ok : ResponseStatus.err,
+    errInfo: hasFile ? null : 'File not found'
+  );
+}
+
 Future<TCPResponse> onFetchFile(TCPRequest request, Socket socket) async {
   try {
     var filePath = await DataBaseHelper().fetchFilePath(msgMd5: request.body['msgmd5'] as String);
@@ -250,9 +262,9 @@ Future<TCPResponse> onFetchContact(TCPRequest request, Socket socket) async {
       type: ResponseType.fromRequestType(request.requestType),
       status: ResponseStatus.ok,
       body: {
-        "contacts": contacts.map((e) => e.jsonObject),
-        "pending": pendingContacts.map((e) => e.jsonObject),
-        "requesting": requestingContacts.map((e) => e.jsonObject)
+        "contacts": contacts.map((e) => e.jsonObject).toList(),
+        "pending": pendingContacts.map((e) => e.jsonObject).toList(),
+        "requesting": requestingContacts.map((e) => e.jsonObject).toList()
       }
     );
   } on Exception catch (exception) {
@@ -264,6 +276,14 @@ Future<TCPResponse> onFetchContact(TCPRequest request, Socket socket) async {
   }
 }
 
+void onAckFetch(TCPRequest request, Socket socket) async {
+  //Update Fetch Histories
+  await DataBaseHelper().setFetchHistoryFor(
+    tokenID: request.tokenID, 
+    newTimeStamp: request.body['timestamp'] as int,
+  );
+}
+
 Future<TCPResponse> onUnknownRequest(TCPRequest request, Socket socket) async {
   return TCPResponse(
     type: ResponseType.fromRequestType(request.requestType),

lib/tcpcontroller/controller.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-08 15:10:04
- * @LastEditTime : 2022-10-09 21:24:07
+ * @LastEditTime : 2022-10-22 21:20:57
  * @Description  : 
  */
 
@@ -9,6 +9,7 @@ import 'dart:async';
 import 'dart:io';
 import 'dart:typed_data';
 
+import 'package:async/async.dart';
 import 'package:tcp_server/tcpcontroller/request.dart';
 import 'package:tcp_server/tcpcontroller/response.dart';
 
@@ -23,28 +24,79 @@ class TCPController {
   //Byte length for subsequent data of the json object
   int payloadLength = 0;
 
+  int _fileCounter = 0;
+
   //Construct a stream which emits events on intact requests
-  StreamController<List<int>> _requestStreamController = StreamController()..close();
+  final StreamController<List<int>> _requestRawStreamController = StreamController();
+  final StreamController<File> _payloadRawStreamController = StreamController();
 
   //Construct a payload stream which forward the incoming byte into temp file
-  StreamController<List<int>> _payloadStreamController = StreamController()..close();
+  StreamController<List<int>> _payloadPullStreamController = StreamController()..close();
 
   //Provide a request stream for caller functions to listen on
-  final StreamController<TCPRequest> _inStreamController = StreamController();
-  Stream<TCPRequest> get inStream => _inStreamController.stream;
+  final StreamController<TCPRequest> _requestStreamController = StreamController();
+  Stream<TCPRequest>? _requestStreamBroadcast;
+  Stream<TCPRequest> get requestStreamBroadcast {
+    _requestStreamBroadcast ??= _requestStreamController.stream.asBroadcastStream();
+    return _requestStreamBroadcast!;
+  }
 
   //Provide a post stream for caller functions to push to
-  final StreamController<TCPResponse> _outStreamController = StreamController();
-  StreamSink<TCPResponse> get outStream => _outStreamController.sink;
+  final StreamController<TCPResponse> _responseStreamController = StreamController();
+  StreamSink<TCPResponse> get outStream => _responseStreamController;
+  Stream<TCPResponse>? _responseStreamBroadcast;
+  Stream<TCPResponse> get responseStreamBroadcast {
+    _responseStreamBroadcast ??= _responseStreamController.stream.asBroadcastStream();
+    return _responseStreamBroadcast!;
+  }
 
   TCPController({
     required this.socket
   }) {
-    socket.listen(socketHandler);
+    print('[L] [CONNECTED]-----------------------');
+    print('[L] Connection Established');
+    print('[L] Remote: ${socket.remoteAddress}:${socket.remotePort}');
+    print('[L] Local: ${socket.address}:${socket.port}');
+    Future(() async {
+      try {
+        await for(var request in socket) {
+          _pullRequest(request);
+          await Future.delayed(const Duration(microseconds: 0));
+        }
+      } catch (e) {
+        _requestStreamController.addError(e);
+        _responseStreamController.addError(e);
+      }
+    }).then((_) {
+      print('[L] [CLOSED   ]-----------------------');
+      print('[L] Connection closed: ${socket.address}:${socket.port}');
+      _requestStreamController.close();
+      _responseStreamController.close();
+    });
+    // socket.listen(
+    //   _pullRequest,
+    //   onError: (e) {
+    //     print(e);
+    //     _requestStreamController.addError(e);
+    //   },
+    //   onDone: () {
+    //     print('[L] [CLOSED   ]-----------------------');
+    //     print('[L] Connection closed: ${socket.address}:${socket.port}<-${socket.remoteAddress}:${socket.remotePort}');
+    //     _requestStreamController.close();
+    //   },
+    //   cancelOnError: true,
+    // );
     //This future never ends, would that be bothersome?
     Future(() async {
-      await for(var response in _outStreamController.stream) {
-        await socket.addStream(response.stream);
+      try{
+        await for(var response in responseStreamBroadcast) {
+          await socket.addStream(response.stream);
+        }
+      } catch (e) {
+        print('[E] [EXCEPTION]-----------------------');
+        print('[E] Adding bytes to socket stream failed');
+        await socket.flush();
+        socket.close();
       }
     });
     //This one will fail if two request are handled simultaneously, which cause a stream
@@ -52,40 +104,48 @@ class TCPController {
     // _outStreamController.stream.listen((response) async {
     //   await socket.addStream(response.stream);
     // });
+    Future(() async {
+      var requestQueue = StreamQueue(_requestRawStreamController.stream);
+      var payloadQueue = StreamQueue(_payloadRawStreamController.stream);
+      while(await Future<bool>(() => !_requestRawStreamController.isClosed && !_payloadRawStreamController.isClosed)) {
+        var request = await requestQueue.next;
+        var payload = await payloadQueue.next;
+        await _pushRequest(requestBytes: request, tempFile: payload);
+      }
+      requestQueue.cancel();
+      payloadQueue.cancel();
+    });
   }
 
   //Listen to the incoming stream and emits event whenever there is a intact request
-  void socketHandler(Uint8List fetchedData) {
+  void _pullRequest(Uint8List fetchedData) {
     //Put incoming data into buffer
     buffer.addAll(fetchedData);
     //Consume buffer until it's not enough for first 8 byte of a message
     while(true) {
-      if(requestLength == 0 && payloadLength == 0 && _payloadStreamController.isClosed) {
+      if(requestLength == 0 && payloadLength == 0 && _payloadPullStreamController.isClosed) {
         //New request
-        if(buffer.length >= 8) {
+        if(buffer.length >= 12) {
           //Buffered data has more than 8 bytes, enough to read request length and body length
           requestLength = Uint8List.fromList(buffer.sublist(0, 4)).buffer.asInt32List()[0];
-          payloadLength = Uint8List.fromList(buffer.sublist(4, 8)).buffer.asInt32List()[0];
+          payloadLength = Uint8List.fromList(buffer.sublist(4, 12)).buffer.asInt64List()[0];
           //Clear the length indicator bytes
-          buffer.removeRange(0, 8);
-          //Create temp file to read payload (might be huge)
-          var tempFile = File('${Directory.current.path}/.tmp/${DateTime.now().microsecondsSinceEpoch}')..createSync();
+          buffer.removeRange(0, 12);
           //Initialize payload transmission controller
-          _payloadStreamController = StreamController();
+          _payloadPullStreamController = StreamController();
           //Create a future that listens to the status of the payload transmission
-          var payloadTransmission = Future(() async {
-            await for(var data in _payloadStreamController.stream) {
-              await tempFile.writeAsBytes(data, mode: FileMode.append, flush: true);
-            }
-          });
-          //Bind request construction on stream
-          _requestStreamController = StreamController();
-          _requestStreamController.stream.listen((requestBytes) {
-            //When request stream is closed by controller
-            payloadTransmission.then((_) {
-              _inStreamController.add(TCPRequest(requestBytes, tempFile));
+          () {
+            var payloadPullStream = _payloadPullStreamController.stream;
+            var tempFile = File('${Directory.current.path}/.data/.tmp/${DateTime.now().microsecondsSinceEpoch}$_fileCounter')..createSync();
+            _fileCounter += 1;
+            _fileCounter %= 1000;
+            Future(() async {
+              await for(var data in payloadPullStream) {
+                await tempFile.writeAsBytes(data, mode: FileMode.writeOnlyAppend);
+              }
+              _payloadRawStreamController.add(tempFile);
             });
-          });
+          }();
         }
         else {
           //Buffered data is not long enough
@@ -100,8 +160,7 @@ class TCPController {
           if(buffer.length >= requestLength) {
             //Got intact request json
             //Emit request buffer through stream
-            _requestStreamController.add(buffer.sublist(0, requestLength));
-            _requestStreamController.close();
+            _requestRawStreamController.add(buffer.sublist(0, requestLength));
             //Remove proccessed buffer
             buffer.removeRange(0, requestLength);
             //Clear awaiting request length
@@ -118,18 +177,18 @@ class TCPController {
           if(buffer.length >= payloadLength) {
             //Last few bytes to emit
             //Send the last few bytes to stream
-            _payloadStreamController.add(Uint8List.fromList(buffer.sublist(0, payloadLength)));
+            _payloadPullStreamController.add(buffer.sublist(0, payloadLength));
             //Clear buffer
             buffer.removeRange(0, payloadLength);
             //Set payload length to zero
             payloadLength = 0;
             //Close the payload transmission stream
-            _payloadStreamController.close();
+            _payloadPullStreamController.close();
           }
           else {
             //Part of payload
             //Transmit all to stream
-            _payloadStreamController.add(Uint8List.fromList(buffer));
+            _payloadPullStreamController.add([...buffer]);
             //Reduce payload bytes left
             payloadLength -= buffer.length;
             //Clear buffer
@@ -141,4 +200,16 @@ class TCPController {
       }
     }
   }
+
+  Future<void> _pushRequest({
+    required List<int> requestBytes,
+    required File tempFile
+  }) async {
+    try{
+      _requestStreamController.add(TCPRequest(requestBytes, tempFile));
+    } catch (e) {
+      print('[E] [EXCEPTION]-----------------------');
+      print('[E] Adding bytes to request stream failed');
+    }
+  }
 }

lib/tcpcontroller/request.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-08 15:14:26
- * @LastEditTime : 2022-10-09 22:56:26
+ * @LastEditTime : 2022-10-22 20:54:40
  * @Description  : 
  */
 import 'dart:convert';
@@ -16,6 +16,7 @@ enum RequestType {
   modifyPassword('MODIFYPASSWD'),   //Modify user password
   modifyProfile ('MODIFYPROFILE'),  //Modify user profile
   sendMessage   ('SENDMSG'),        //Send message
+  ackFetch      ('ACKFETCH'),       //Ack fetched messages, update fetch history
   fetchMessage  ('FETCHMSG'),       //Fetch message
   findFile      ('FINDFILE'),       //Find file by md5 before transmitting the file
   fetchFile     ('FETCHFILE'),      //Fetch file and file md5 by message md5
@@ -40,6 +41,16 @@ class TCPRequest {
   File? payload;
 
   TCPRequest(List<int> data, this.payload): _data = jsonDecode(String.fromCharCodes(data));
+  TCPRequest.fromData({
+    required RequestType type, 
+    required Map<String, Object?> body, 
+    required int? tokenID,
+    this.payload
+  }): _data = {
+    'request': type.value,
+    'tokenid': tokenID,
+    'body': body
+  };
   TCPRequest.none(): _data = {};
 
   String get toJSON => jsonEncode(_data);

lib/tcpcontroller/response.dart

@@ -1,7 +1,7 @@
 /*
  * @Author       : Linloir
  * @Date         : 2022-10-08 22:40:47
- * @LastEditTime : 2022-10-09 16:39:02
+ * @LastEditTime : 2022-10-18 14:44:49
  * @Description  : 
  */
 
@@ -72,11 +72,11 @@ class TCPResponse {
     }), 
     payloadFile = payload;
 
-  int get responseLength => responseJson.length;
+  int get responseLength => responseJson.codeUnits.length;
   int get payloadLength => payloadFile?.lengthSync() ?? 0;
   Stream<List<int>> get stream async* {
     yield Uint8List(4)..buffer.asInt32List()[0] = responseLength;
-    yield Uint8List(4)..buffer.asInt32List()[0] = payloadLength;
+    yield Uint8List(8)..buffer.asInt64List()[0] = payloadLength;
     yield Uint8List.fromList(responseJson.codeUnits);
     if(payloadFile != null) {
       yield await payloadFile!.readAsBytes();

license

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.
+
+  Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+  For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+  Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+  Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
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+"recipients" may be individuals or organizations.
+
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pubspec.lock

@@ -23,7 +23,7 @@ packages:
     source: hosted
     version: "2.3.1"
   async:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: async
       url: "https://pub.flutter-io.cn"

pubspec.yaml

@@ -12,6 +12,7 @@ dependencies:
   sqflite_common: ^2.3.0
   crypto: ^3.0.2
   convert: ^3.0.2
+  async: ^2.9.0
 
 # dependencies:
 #   path: ^1.8.0