我有一个 WebSocket
创建每个连接参与者处理程序的 Controller :
class WebSocketController @Inject()(cc: ControllerComponents)(implicit exc: ExecutionContext) {
def socket: WebSocket = WebSocket.accept[JsValue, JsValue] { request =>
ActorFlow.actorRef { out => // Flow that is handled by an actor from 'out' ref
WebSocketActor.props(out) // Create an actor for new connected WebSocket
}
}
}
在 Actor 处理程序中,我需要使用
ReactiveMongo
:trait ModelDAO extends MongoController with ReactiveMongoComponents {
val collectionName: String
...
}
class UsersCollection @Inject()(val cc: ControllerComponents,
val reactiveMongoApi: ReactiveMongoApi,
val executionContext: ExecutionContext,
val materializer: Materializer)
extends AbstractController(cc) with ModelDAO {
val collectionName: String = "users"
}
所以,通常的方法是 @Inject()
UsersCollection
在目标类中。但我不能做这样的事情:class WebSocketActor @Inject()(out: ActorRef, users: UsersCollection) extends Actor { ... }
因为actor实例在
WebSocketActor
内部创建伴生对象:object WebSocketActor {
def props(out: ActorRef) = Props(new WebSocketActor(out))
}
如何使用
UsersCollection
里面WebSocketActor
?
最佳答案
您可以创建 Actor 谁的依赖项将由 Play 自动注入(inject)。没问题。 (https://www.playframework.com/documentation/2.6.x/ScalaAkka)
但是如果是网络套接字, Prop 预期的 Actor ,但不是 Actor (或 ActorRef)本身。
ActorFlow.actorRef { out => // Flow that is handled by an actor from 'out' ref
WebSocketActor.props(out) // <- ACTOR IS NOT CREATED HERE, WE RETURN PROPS
}
所以在这种情况下没有办法自动完成(至少我没有找到它)。
你可以做的是通过
UsersCollection
手动。class WebSocketController @Inject()(cc: ControllerComponents, usersCollection: UsersCollection)(implicit exc: ExecutionContext) {
def socket: WebSocket = WebSocket.accept[JsValue, JsValue] { request =>
ActorFlow.actorRef { out => // Flow that is handled by an actor from 'out' ref
WebSocketActor.props(out, usersCollection) //<- ACTOR IS NOT CREATED HERE, WE RETURN PROPS
}
}
}
注意到我注入(inject)了
UsersCollection
进入 WebSocketController
并将其传递给 Prop 。简单,我没有看到任何缺点。
关于scala - 如何将()注入(inject)到具有构造函数参数的类中?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46252946/