2.4 As actor中的依赖注入

Question

在 Play 2.3 中，我们可以创建一个扩展来为 Akka actor 依赖注入设置默认注入器。迁移到 2.4 后，我们不再需要创建注入器。我们如何重用 Play's injector 来向 Akka actor 注入依赖？

我们有一个 GuiceExtensionProvider 这样的：

/**
 * An Akka Extension Provider
 */
object GuiceExtensionProvider extends ExtensionId[GuiceExtension] with ExtensionIdProvider {

  override def lookup = GuiceExtensionProvider

  /**
   * Is used by Akka to instantiate the Extension identified by this ExtensionId, internal use only.
   */
  override def createExtension(system: ExtendedActorSystem): GuiceExtension = new GuiceExtension(system)

}

/**
 * The Extension implementation.
 */
class GuiceExtension(system: ExtendedActorSystem) extends Extension {

  private var injector: Injector = _

  /**
   * Used to initialize the Guice Injector for the extension.
   */
  def initialize(injector: Injector) = this.injector = injector

  /**
   * Create a Props for the specified actorType using the GuiceActorProducer class.
   *
   * @param actorType The type of the actor to create Props for
   * @return a Props that will create the typed actor bean using Guice
   */
  def props(actorType: Type): Props = Props(classOf[GuiceActorProducer], injector, actorType)

}

当系统启动时，我们将调用这些来初始化扩展：

class MyModule extends ScalaModule {
  def configure() {
  }
}
val injector = Guice.createInjector(new MyModule()) <--- `How can we use the default injector from Play?`
GuiceExtensionProvider(Akka.system).initialize(injector)

这是我们用来初始化 actor 的方式：Akka.system.actorOf(GuiceExtensionProvider(Akka.system).props(classOf[EmailActor]), "emailActor")

Answer 1

Play 框架有关于这个主题的很好的文档： Play scala/akka dependency injection integration

在父 actor 上，您只需要使用 @Inject 并声明一个具有 AkkaGuiceSupport 特征的 Guice 模块。比你可以使用 @Named 注释注入你的演员。儿童演员有点棘手，你必须使用 Guice's assisted inject.

2.4 As actor中的依赖注入

Play 2.4 dependency injection in Akka actors

scala

akka

playframework

playframework-2.3

playframework-2.4