详解在.net core中完美解决多租户分库分表的问题_ASP.NET教程

详解在.net core中完美解决多租户分库分表的问题

2020-06-29 14:29hubro ASP.NET教程

这篇文章主要介绍了详解在.net core中完美解决多租户分库分表的问题，文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

前几天有人想做一个多租户的平台,每个租户一个库,可以进行水平扩展,应用端根据登录信息,切换到不同的租户库

计划用ef core实现,他们说做不出来,需要动态创建dbContext,不好实现

然而这个使用CRL很轻松就能解决了

以下为演示数据库,有两个库testdb和testdb2,查询结果如下

详解在.net core中完美解决多租户分库分表的问题

目标:

根据传入登录信息连不不同的库,查询返回结果,如登录人为01,返回d1.default,登录人为02 返回 d2.default

实际上这个需求就是分库分表的实现,通过设置数据库/表映射关系,根据传入的定位数据进行匹配,找到正确的库表配置,生成数据访问对象

以core控制台程序为例

									class Program

									  {

									    static IServiceProvider provider;

									    static Program()

									    {

									      var services = new ServiceCollection();

									      services.AddCRL<DBLocationCreator>();

									      services.AddScoped<Code.Sharding.MemberManage>();

									      provider = services.BuildServiceProvider();

									      provider.UseCRL();

									    }

									    static void Main(string[] args)

									    {

									    label1:

									      var instance = provider.GetService<Code.Sharding.MemberManage>();

									      var data = new Code.Sharding.MemberSharding();

									      data.Code = "01";

									      instance.SetLocation(data);

									      var find1 = instance.QueryItem(b => b.Id > 0)?.Name;

									      Console.WriteLine($"定位数据输入{data.Code},查询值为{find1}");

									      data.Code = "02";

									      instance.SetLocation(data);

									      var find2 = instance.QueryItem(b => b.Id > 0)?.Name;

									      Console.WriteLine($"定位数据输入{data.Code},查询值为{find2}");

									      Console.ReadLine();

									      goto label1;

									    }

									  }

上面代码中,通过SetLocation方法传入定位数据Code,通过QueryItem方法查询出数据并打印出来

通过services.AddCRL<DBLocationCreator>()注入定位配置,DBLocationCreator继承了接口IDBLocationCreator

这里完全符合core注入规范,可以通过配置或数据库存储动态读取定位设置

									public class DBLocationCreator : IDBLocationCreator

									  {

									    ISettingConfigBuilder _settingConfigBuilder;

									    public DBLocationCreator(ISettingConfigBuilder settingConfigBuilder)

									    {

									      _settingConfigBuilder = settingConfigBuilder;

									    }

									    public void Init()

									    {

									      //自定义定位

									      _settingConfigBuilder.RegisterLocation<Code.Sharding.MemberSharding>((t, a) =>

									      {

									        var tableName = t.TableName;

									        var dbName = a.Code == "02" ? "testdb2" : "testdb";

									        var dataBase = $"Data Source=.;Initial Catalog={dbName};User ID=sa;Password=123";

									        //返回定位库和表名

									        return new CRL.Sharding.Location(dataBase, tableName);

									      });

									      _settingConfigBuilder.RegisterDBAccessBuild(dbLocation =>

									      {

									        var connectionString = "Data Source=.;Initial Catalog=testdb;User ID=sa;Password=123";

									        if (dbLocation.ShardingLocation != null)

									        {

									          connectionString = dbLocation.ShardingLocation.DataBaseSource;

									        }

									        return new CRL.DBAccessBuild(DBType.MSSQL, connectionString);

									      });

									    }

									  }