Play框架Scala应用程序(数据库)中的数据库事务

问题描述：

我正在使用Play框架和scala开发应用程序.我正在将anorm用于数据访问层.我有一个我无法解决的问题.

I am developing an application using Play framework and scala. I am using anorm for data-access layer. And I've got a problem I could not solve.

简介:我希望能够在数据访问对象(dao)中拥有一些方法，以便在事务内部工作以及被单独调用.

Brief: I want to be able to have methods in data-access objects (dao) to work inside transactions as well as being called alone.

详细信息:

我的数据访问层由类组成，这些类仅具有通过数据库执行特定SQL的方法.传统上，它们看起来像:

I have data-access layer consist of class with methods that only executes particular SQL over database. Traditionally they looks like:

def list() = DB.withConnection { implicit cn =>
  ...
}

现在，我想在事务范围内执行一些方法.类似于传统的选择更新服务方法，但仍然能够单独运行它们.所以，我的想法是这样的:

Now I want to have some methods to be executed in a transaction scope. Like traditional select-update service methods but still be able to run them alone. So, what I have in my mind is like this:

class Service {
  def fooTransacted() = {
    inTransaction {
      val old = dao.select(id = 2)
      val newObj = old.copy(isActive = true)
      dao.update(newObj)
    }
  }

  def fooSinle() = {
    dao.select(id = 2)
  }
}

我尝试了几种方法，但无法提出任何解决方案.

I tried around several ways, but could not come up with any solution.

答

那

class Dao {
  def foo(id: Long)(implicit connection: Connection) = {
    SQL("select * from foo where id={id}").on('id->id).as(...)
  }
}

class Service{
  def withConnection = {
    DB.withConnection {implicit connection =>
      Dao.foo(1)
      Dao.foo(2)
    }
  }

  def withTransaction = {
    DB.withTransaction {implicit connection =>
      Dao.foo(1)
      Dao.foo(2)
  }
}

Play框架Scala应用程序(数据库)中的数据库事务

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