/*
* @Copyright (c) Huawei Technologies Co., Ltd. 2023-2024. All rights reserved.
*/
package mysqlclient_ffi
/*
* 定义数据库事务的核心行为
*/
public class MysqlTransaction <: Transaction {
private var mysql: CPointer<Unit>
private var mysqlConnection: MysqlConnection
/*
* 初始化数据库事务
*
* 参数 mysql - 初始化的mysql
*/
init(mysql: CPointer<Unit>, mysqlConnection: MysqlConnection) {
this.mysql = mysql
this.mysqlConnection = mysqlConnection
}
/*
* 数据库事务隔离级别。
* 没有提供直接获取数据库事务隔离级别的接口或属性。但是，可以通过执行 SQL 语句来查询事务隔离级别，
*
* 异常 SqlException - 数据库事务隔离级别获取设置失败。
*/
public mut override prop isoLevel: TransactionIsoLevel {
get() {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
let sql = "SELECT @@transaction_isolation"
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
let res: CPointer<Unit> = mysql_use_result(mysql)
let row: CPointer<CString> = mysql_fetch_row(res)
let tmp: String = row.read().toString()
LibC.free(sqlcstr)
mysql_free_result(res)
match (tmp.toAsciiLower()) {
case "chaos" => return TransactionIsoLevel.Chaos
case "default" => return TransactionIsoLevel.Unspecified
case "linearizable" => return TransactionIsoLevel.Linearizable
case "read-committed" => return TransactionIsoLevel.ReadCommitted
case "read-uncommitted" => return TransactionIsoLevel.ReadUncommitted
case "repeatable-read" => return TransactionIsoLevel.RepeatableRead
case "serializable" => return TransactionIsoLevel.Serializable
case "snapshot" => return TransactionIsoLevel.Snapshot
case _ => throw SqlException("unknown TransactionIsoLevel Type: ${tmp}")
}
}
}
set(value) {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
var sql = match (value) {
case TransactionIsoLevel.ReadCommitted => "SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED"
case TransactionIsoLevel.ReadUncommitted => "SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED"
case TransactionIsoLevel.RepeatableRead => "SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ"
case TransactionIsoLevel.Serializable => "SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE"
case TransactionIsoLevel.Unspecified => "SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ"
case _ => throw SqlException("unsupport TransactionIsoLevel Type: ${value}")
}
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
LibC.free(sqlcstr)
}
}
}
/*
* 数据库事务访问模式。
* 没有提供直接获取数据库事务隔离级别的接口或属性。但是，可以通过执行 SQL 语句来查询事务隔离级别，
* 返回一个值 0 或 1。如果值是 0，表示事务访问模式是读写模式；如果值是 1，表示事务访问模式是只读模式
*
* 异常 SqlException - 数据库事务访问模式获取设置失败。
*/
public mut override prop accessMode: TransactionAccessMode {
get() {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
let sql = "SELECT @@transaction_read_only"
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
let res: CPointer<Unit> = mysql_use_result(mysql)
let row: CPointer<CString> = mysql_fetch_row(res)
let tmp: String = row.read().toString()
LibC.free(sqlcstr)
mysql_free_result(res)
match (tmp.toAsciiLower()) {
case "0" => return TransactionAccessMode.ReadWrite
case "1" => return TransactionAccessMode.ReadOnly
case _ => throw SqlException("unknown TransactionAccessMode Type: ${tmp}")
}
}
}
set(value) {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
var sql = ""
match (value) {
case TransactionAccessMode.ReadWrite => sql = "SET SESSION transaction_read_only = OFF"
case TransactionAccessMode.ReadOnly => sql = "SET SESSION transaction_read_only = ON"
case TransactionAccessMode.Unspecified => sql = "SET SESSION transaction_read_only = OFF"
}
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
LibC.free(sqlcstr)
}
}
}
/*
* 数据库事务延迟模式。(不支持)
* 仅PostgreSQL和PostgreSQL支持
*/
public mut override prop deferrableMode: TransactionDeferrableMode {
get() {
return TransactionDeferrableMode.Deferrable
}
set(_) {
}
}
/*
* 开始数据库事务。
*
* 异常 SqlException - 开始数据库事务失败。
*/
public override func begin(): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
// 设置自动提交模式
let isBool: Bool = mysql_autocommit(mysql, false)
if (isBool) {
throw SqlException(mysql_error(mysql).toString())
}
}
}
/*
* 提交数据库事务。
*
* 异常 SqlException - 提交数据库事务失败。
*/
public override func commit(): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
// 提交事务
let isBool: Bool = mysql_commit(mysql)
if (isBool) {
throw SqlException(mysql_error(mysql).toString())
}
}
}
/*
* 从挂起状态回滚事务。
*
* 异常 SqlException - 从挂起状态回滚事务失败。
*/
public override func rollback(): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
// 回滚事务
let isBool: Bool = mysql_rollback(mysql)
if (isBool) {
throw SqlException(mysql_error(mysql).toString())
}
}
}
/*
* 在事务中创建一个指定名称的保存点，可用于回滚事务的一部分。
*
* 参数 savePointName - 保存点名称。
* 异常 SqlException - 提交事务时服务器端发生错误或者事务已提交或回滚或连接已断开。
*/
public override func save(savePointName: String): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
let sql = "SAVEPOINT ${savePointName}"
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
LibC.free(sqlcstr)
}
}
/*
* 回滚事务至指定保存点名称。
*
* 参数 savePointName - 保存点名称。
* 异常 SqlException - 提交事务时服务器端发生错误或者事务已提交或回滚或连接已断开。
*/
public override func rollback(savepointName: String): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
let sql = "rollback to SAVEPOINT ${savepointName}"
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
LibC.free(sqlcstr)
}
}
/*
* 销毁先前在当前事务中定义的保存点。这允许系统在事务结束之前回收一些资源。
*
* 参数 savePointName - 保存点名称。
* 异常 SqlException - 提交事务时服务器端发生错误或者事务已提交或回滚或连接已断开。
*/
public override func release(savePointName: String): Unit {
if(mysqlConnection.isClosed()){
throw SqlException("The database connection has been closed")
}
unsafe {
let sql = "RELEASE SAVEPOINT ${savePointName}"
let sqlcstr: CString = LibC.mallocCString(sql)
if (mysql_query(mysql, sqlcstr) != 0) {
LibC.free(sqlcstr)
throw SqlException(mysql_error(mysql).toString())
}
LibC.free(sqlcstr)
}
}
}