[Architect] Abp 框架原理解析(5) UnitOfWork

本节目录

• 介绍
• 分析Abp源码
• 实现UOW

 

介绍

UOW(全称UnitOfWork)是指工作单元.

在Abp中,工作单元对于仓储和应用服务方法默认开启。并在一次请求中,共享同一个工作单元.

同时在Abp中,不仅支持同一个数据库连接,还支持事务处理.

 

分析Abp源码

1.UnitOfWorkRegistrar

 

2.ComponentRegistered

 

 

3.IsConventionalUowClass

 

 

4.Intercept

 

 

5.PerformSyncUow

 

 

 

实现UOW

定义IUnitOfWork

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public interface IUnitOfWork {     //1.开启事务     //2.设置Filter(本例中不做演示)     void Begin(UnitOfWorkOptions options);     void Complete(); } public class UnitOfWorkOptions {     public bool? IsTransactional { get; set; } }

 

实现uow,在uow中会提供db的创建,这样才能管理到每个db.

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public class EfUnitOfWork : UnitOfWorkBase {     public static DbContext DbContext { get; set; }     public static DbContext GetDbContext()     {         if (DbContext == null)         {             DbContext = new DemoDb();         }         return DbContext;     }     public override void Begin(UnitOfWorkOptions options)     {         if (options.IsTransactional == true)         {             CurrentTransaction = new TransactionScope();         }     }     public TransactionScope CurrentTransaction { get; set; }     public override void Complete()     {         SaveChanges();         if (CurrentTransaction != null)         {             CurrentTransaction.Complete();         }     }     private void SaveChanges()     {         DbContext.SaveChanges();     } } public abstract class UnitOfWorkBase : IUnitOfWork {     public virtual void Begin(UnitOfWorkOptions options)     {     }     public virtual void Complete()     {     } }

 

定义与实现仓储层,这里不再做DbProvider.

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public interface IRepository { } public interface ITaskRepository : IRepository {     void Add(Task task); } public class TaskRepository : ITaskRepository {     public void Add(Task task)     {         var db = (DemoDb)EfUnitOfWork.GetDbContext();         db.Tasks.Add(task);     } }

 

定义与实现应用层

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public interface IApplicationService { } public interface ITaskAppService : IApplicationService {     void CreateTask(CreateTaskInput input); } public class TaskAppService : ITaskAppService {     private ITaskRepository _repository;     public TaskAppService(ITaskRepository repository)     {         _repository = repository;     }     public void CreateTask(CreateTaskInput input)     {         _repository.Add(new Task(input.Name));     } } public class CreateTaskInput {     public string Name { get; set; } }

 

定义与实现uow拦截器

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internal class UnitOfWorkInterceptor : IInterceptor {     private IUnitOfWork _unitOfWork;     public UnitOfWorkInterceptor(IUnitOfWork unitOfWork)     {         _unitOfWork = unitOfWork;     }     public void Intercept(IInvocation invocation)     {         _unitOfWork.Begin(new UnitOfWorkOptions());         invocation.Proceed();         _unitOfWork.Complete();     } }

 

定义在IApplicationService与IRepository接口下拦截

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static void Kernel_ComponentRegistered(string key, Castle.MicroKernel.IHandler handler) {     var type = handler.ComponentModel.Implementation;     if (typeof(IApplicationService).IsAssignableFrom(type) || typeof(IRepository).IsAssignableFrom(type))     {         handler.ComponentModel.Interceptors.Add(new InterceptorReference(typeof(UnitOfWorkInterceptor)));     } }

 

执行

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static void Main(string[] args) {     using (var container = new WindsorContainer())     {         container.Register(Component.For<IInterceptor, UnitOfWorkInterceptor>());//先注入拦截器         container.Register(Component.For<IUnitOfWork, EfUnitOfWork>());         container.Kernel.ComponentRegistered += Kernel_ComponentRegistered;         container.Register(Component.For<ITaskAppService, TaskAppService>());         container.Register(Component.For<ITaskRepository, TaskRepository>());         var person = container.Resolve<ITaskAppService>();         person.CreateTask(new CreateTaskInput() { Name = "3333" });     }     Console.ReadKey(); }

 

会自动在application method的结尾调用Complete.

另外也可以在uow上定义option为启用事务.在本例中稍作扩展即可实现.