Question

假设有两个存储库接口：

interface IFooRepository
{
    void Delete(int id);
}

interface IBarRepository
{
    void Delete(int id);
}

和IUnitOfWork界面如：

interface IUnitOfWork : IDisposable
{
    void Commit();
    void Rollback();
}

使用ServiceStack.ORMLite实现这些界面的最佳实践是什么，以便用户可以像

一样使用它们

MyFooRepository.Delete(4);
// if an Exception throws here, Bar won't be deleted
MyBarRepository.Delete(7);

或者

using (var uow = CreateUnitOfWork())
{
    MyFooRepository.Delete(4);
    MyBarRepository.Delete(7);
    uow.Commit();  //now they are in an transaction
}

Answer 1

不确定是否需要Repository + UnitOfWork模式，但我认为ServiceStack + OrmLite中有一些替代解决方案可以在您需要引入任何模式之前保持代码“DRY”（特别是如果您主要寻求事务/回滚）支持）。下面的内容就是我要开始的地方。

public class Foo //POCO for data access
{
    //Add Attributes for Ormlite
    public int Id { get; set;  }
}

public class Bar //POCO for data access
{
    //Add Attributes for Ormlite
    public int Id { get; set; }
}

//your request class which is passed to your service
public class DeleteById 
{
    public int Id { get; set; }
}

public class FooBarService : MyServiceBase //MyServiceBase has resusable method for handling transactions. 
{
    public object Post(DeleteById request)
    {
        DbExec(dbConn =>
                   {
                       dbConn.DeleteById<Foo>(request.Id);
                       dbConn.DeleteById<Bar>(request.Id);
                   });

        return null;
    }
}

public class MyServiceBase : Service
{
    public IDbConnectionFactory DbFactory { get; set; }

    protected void DbExec(Action<IDbConnection> actions)
    {
        using (var dbConn = DbFactory.OpenDbConnection())
        {
            using (var trans = dbConn.OpenTransaction())
            {
                try
                {
                    actions(dbConn);
                    trans.Commit();
                }
                catch (Exception ex)
                {
                    trans.Rollback();
                    throw ex;
                }
            }
        }
    }
}

一些参考文献......

https://github.com/ServiceStack/ServiceStack.RedisWebServices - 上述代码已从此示例中修改

https://groups.google.com/forum/#!msg/servicestack/1pA41E33QII/R-trWwzYgjEJ - 讨论ServiceStack中的图层

http://ayende.com/blog/3955/repository-is-the-new-singleton - 存储模式上的Ayende Rahien（NHibernate核心贡献者）

使用ServiceStack.ORMLite实现工作单元和存储库模式的最佳实践

1 个答案: