From 91ee5d1d0eb16c1a3cac0edbbabca724725b5f75 Mon Sep 17 00:00:00 2001
From: sunkaixuan <610262374@qq.com>
Date: Sun, 24 Jul 2022 16:39:29 +0800
Subject: [PATCH] Add new  optimistic lock

---
 .../UpdateProvider/UpdateableProvider.cs      | 39 ++++++++++++++++++-
 Src/Asp.Net/SqlSugar/Interface/IUpdateable.cs |  2 +
 Src/Asp.Net/SqlSugar/Utilities/UtilMethods.cs | 24 ++++++++++++
 3 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/Src/Asp.Net/SqlSugar/Abstract/UpdateProvider/UpdateableProvider.cs b/Src/Asp.Net/SqlSugar/Abstract/UpdateProvider/UpdateableProvider.cs
index a1d01657f..32f21cdb5 100644
--- a/Src/Asp.Net/SqlSugar/Abstract/UpdateProvider/UpdateableProvider.cs
+++ b/Src/Asp.Net/SqlSugar/Abstract/UpdateProvider/UpdateableProvider.cs
@@ -59,6 +59,15 @@ namespace SqlSugar
             var sqlObj = this.ToSql();
             this.Context.Queues.Add(sqlObj.Key, sqlObj.Value);
         }
+
+        public virtual int ExecuteCommandWithOptLock()
+        {
+            var updateData = UpdateObjs.FirstOrDefault();
+            if (updateData == null) return 0;
+            _ExecuteCommandWithOptLock(updateData);
+            return this.ExecuteCommand();
+        }
+
         public virtual int ExecuteCommand()
         {
             string sql = _ExecuteCommand();
@@ -74,6 +83,13 @@ namespace SqlSugar
         {
             return this.ExecuteCommand() > 0;
         }
+        public virtual async Task<int> ExecuteCommandWithOptLockAsync()
+        {
+            var updateData = UpdateObjs.FirstOrDefault();
+            if (updateData == null) return 0;
+            _ExecuteCommandWithOptLock(updateData);
+            return await this.ExecuteCommandAsync();
+        }
         public virtual async Task<int> ExecuteCommandAsync()
         {
             string sql = _ExecuteCommand();
@@ -852,7 +868,28 @@ namespace SqlSugar
                 this.RemoveCacheFunc();
             }
         }
-
+        private void _ExecuteCommandWithOptLock(T updateData)
+        {
+            Check.ExceptionEasy(UpdateParameterIsNull == true, "Optimistic lock can only be an entity update method", "乐观锁只能是实体更新方式");
+            var verColumn = this.EntityInfo.Columns.FirstOrDefault(it => it.IsEnableUpdateVersionValidation);
+            Check.ExceptionEasy(verColumn == null, $" {this.EntityInfo.EntityName } need  IsEnableUpdateVersionValidation=true ", $"实体{this.EntityInfo.EntityName}没有找到版本标识特性 IsEnableUpdateVersionValidation");
+            Check.ExceptionEasy(UpdateObjs.Length > 1, $"Optimistic lock can only handle a single update ", $"乐观锁只能处理单条更新");
+            Check.ExceptionEasy(!verColumn.UnderType.IsIn(UtilConstants.StringType, UtilConstants.LongType, UtilConstants.GuidType, UtilConstants.DateType), $"Optimistic locks can only be guid, long, and string types", $"乐观锁只能是Guid、Long和字符串类型");
+            var oldValue = verColumn.PropertyInfo.GetValue(updateData);
+            var newValue = UtilMethods.GetRandomByType(verColumn.UnderType);
+            verColumn.PropertyInfo.SetValue(updateData, newValue);
+            var data = this.UpdateBuilder.DbColumnInfoList.First(it =>
+            it.PropertyName.EqualCase(verColumn.PropertyName));
+            data.Value = newValue;
+            var pks = GetPrimaryKeys();
+            this.Where(verColumn.DbColumnName, "=", oldValue);
+            foreach (var p in pks)
+            {
+                var pkColumn = this.EntityInfo.Columns.FirstOrDefault(
+                    it => it.DbColumnName.EqualCase(p) || it.PropertyName.EqualCase(p));
+                this.Where(pkColumn.DbColumnName, "=", pkColumn.PropertyInfo.GetValue(updateData));
+            }
+        }
         private void Before(string sql)
         {
             if (this.IsEnableDiffLogEvent)
diff --git a/Src/Asp.Net/SqlSugar/Interface/IUpdateable.cs b/Src/Asp.Net/SqlSugar/Interface/IUpdateable.cs
index 56e5703b4..430e830d6 100644
--- a/Src/Asp.Net/SqlSugar/Interface/IUpdateable.cs
+++ b/Src/Asp.Net/SqlSugar/Interface/IUpdateable.cs
@@ -12,6 +12,8 @@ namespace SqlSugar
         UpdateBuilder UpdateBuilder { get; set; }
         bool UpdateParameterIsNull { get; set; }
 
+        int ExecuteCommandWithOptLock();
+        Task<int> ExecuteCommandWithOptLockAsync();
         int ExecuteCommand();
         bool ExecuteCommandHasChange();
         Task<int> ExecuteCommandAsync();
diff --git a/Src/Asp.Net/SqlSugar/Utilities/UtilMethods.cs b/Src/Asp.Net/SqlSugar/Utilities/UtilMethods.cs
index 8ff8b35f1..2ac280d1c 100644
--- a/Src/Asp.Net/SqlSugar/Utilities/UtilMethods.cs
+++ b/Src/Asp.Net/SqlSugar/Utilities/UtilMethods.cs
@@ -133,6 +133,30 @@ namespace SqlSugar
             };
         }
 
+        internal static object GetRandomByType(Type underType)
+        {
+            if (underType == UtilConstants.GuidType)
+            {
+                return Guid.NewGuid();
+            }
+            else if (underType == UtilConstants.LongType)
+            {
+                return SnowFlakeSingle.Instance.NextId();
+            }
+            else if (underType == UtilConstants.StringType)
+            {
+                return Guid.NewGuid() + "";
+            }
+            else if (underType == UtilConstants.DateType)
+            {
+                return System.DateTime.Now;
+            }
+            else 
+            {
+                return Guid.NewGuid() + "";
+            }
+        }
+
         public static bool IsAsyncMethod(MethodBase method)
         {
             if (method == null)