// // DataManager.swift // GRDBDemo // // Created by Apple on 2021/4/21. // import GRDB struct DataBaseName { /// 数据库名字 static let test = "conversation.db" } /// 数据库表名 struct TableName { static let message = "ChatMessage" } /// 数据库连接 class DBManager: NSObject { /// 数据库路径 private static var dbPath: String = { // 获取工程内容数据库名字 let filePath: String = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true).first!.appending("/\(DataBaseName.test)") //print("数据库地址：", filePath as Any) return filePath }() /// 数据库配置 private static var configuration: Configuration = { // 配置 var configuration = Configuration() // 设置超时 configuration.busyMode = Database.BusyMode.timeout(5.0) // 试图访问锁着的数据 //configuration.busyMode = Database.BusyMode.immediateError return configuration }() // MARK: 创建数据 多线程 /// 数据库 用于多线程事务处理 static var dbQueue: DatabaseQueue = { // 创建数据库 let db = try! DatabaseQueue(path: DBManager.dbPath, configuration: DBManager.configuration) db.releaseMemory() // 设备版本 return db }() }
// // ChatMessage.swift // GRDBDemo // // Created by Apple on 2021/4/21. // import Foundation import GRDB /// 聊天消息类 struct ChatMessage: Codable { var messageId : String? var messageType : String? var messageContent : String? var senderId : String? var targetId : String? private enum Columns: String, CodingKey, ColumnExpression { case messageId case messageType case messageContent case senderId case targetId } } extension ChatMessage: MutablePersistableRecord, FetchableRecord { /// 获取数据库对象 private static let dbQueue: DatabaseQueue = DBManager.dbQueue //MARK: 创建 /// 创建数据库 private static func createTable() -> Void { try! self.dbQueue.inDatabase { (db) -> Void in // 判断是否存在数据库 if try db.tableExists(TableName.message) { debugPrint("表已经存在") return } // 创建数据库表 try db.create(table: TableName.message, temporary: false, ifNotExists: true, body: { (t) in t.column(Columns.messageId.rawValue, Database.ColumnType.text) t.column(Columns.messageType.rawValue, Database.ColumnType.text) t.column(Columns.messageContent.rawValue, Database.ColumnType.text) t.column(Columns.senderId.rawValue, Database.ColumnType.text) t.column(Columns.targetId.rawValue, Database.ColumnType.text) }) } } //MARK: 插入 /// 插入单个数据 static func insert(message: ChatMessage) -> Void { // 判断是否存在 guard ChatMessage.query(messageId: message.messageId!) == nil else { debugPrint("插入消息 内容重复") // 更新 self.update(message: message) return } // 创建表 self.createTable() // 事务 try! self.dbQueue.inTransaction { (db) -> Database.TransactionCompletion in do { var messageTemp = message // 插入到数据库 try messageTemp.insert(db) return Database.TransactionCompletion.commit } catch { return Database.TransactionCompletion.rollback } } } //MARK: 查询一条记录 static func query(messageId: String) -> ChatMessage? { // 创建数据库 self.createTable() // 返回查询结果 return try! self.dbQueue.unsafeRead({ (db) -> ChatMessage? in return try ChatMessage.filter(Column(Columns.messageId.rawValue) == messageId).fetchOne(db) }) } //MARK:查询与某人聊天的多条记录 - 从第几页开始 static func query(userId:String,page:Int) -> [ChatMessage] { // 创建数据库 self.createTable() return try! self.dbQueue.unsafeRead({ (db) -> [ChatMessage] in return try ChatMessage.fetchAll(db, sql: "Select * from ChatMessage where senderId = ‘\(userId)‘ or targetId = ‘\(userId)‘ limit \(20 * page),20") }) } /// 查询所有 static func queryAll() -> [ChatMessage] { // 创建数据库 self.createTable() // 返回查询结果 return try! self.dbQueue.unsafeRead({ (db) -> [ChatMessage] in return try ChatMessage.fetchAll(db) }) } //MARK: 更新 /// 更新 static func update(message: ChatMessage) -> Void { /// 创建数据库表 self.createTable() // 事务 更新场景 try! self.dbQueue.inTransaction { (db) -> Database.TransactionCompletion in do { // 赋值 try message.update(db) return Database.TransactionCompletion.commit } catch { return Database.TransactionCompletion.rollback } } } //MARK: 删除 /// 根据messageId删除聊天记录 static func delete(messageId: String) -> Void { // 查询 guard let message = self.query(messageId: messageId) else { return } // 删除 self.delete(message: message) } /// 删除单个聊天信息 static func delete(message: ChatMessage) -> Void { // 是否有数据库表 self.createTable() // 事务 try! self.dbQueue.inTransaction { (db) -> Database.TransactionCompletion in do { // 删除数据 try message.delete(db) return Database.TransactionCompletion.commit } catch { return Database.TransactionCompletion.rollback } } } }
使用示例：
override func viewWillAppear(_ animated: Bool) { super.viewWillAppear(animated) let user1 = ChatMessage(messageId: "1010", messageType: "text", messageContent: "12345", senderId: "1", targetId: "2") ChatMessage.insert(message: user1) let user2 = ChatMessage(messageId: "1012", messageType: "text", messageContent: "12345", senderId: "123", targetId: "2") ChatMessage.insert(message: user2) let user3 = ChatMessage(messageId: "1013", messageType: "text", messageContent: "12345", senderId: "1", targetId: "123") ChatMessage.insert(message: user3) let user4 = ChatMessage(messageId: "1014", messageType: "text", messageContent: "12345", senderId: "1", targetId: "2") ChatMessage.insert(message: user4) let user5 = ChatMessage(messageId: "1015", messageType: "text", messageContent: "12345", senderId: "1", targetId: "123") ChatMessage.insert(message: user5) let user6 = ChatMessage(messageId: "1016", messageType: "text", messageContent: "12345", senderId: "123", targetId: "2") ChatMessage.insert(message: user6) let user7 = ChatMessage(messageId: "1017", messageType: "text", messageContent: "12345", senderId: "1", targetId: "2") ChatMessage.insert(message: user7) let user8 = ChatMessage(messageId: "1018", messageType: "text", messageContent: "12345", senderId: "1", targetId: "123") ChatMessage.insert(message: user8) let message1 = ChatMessage.query(userId: "123", page: 0) print(message1) }