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How to enter parameters into a class / method method in Scala

I have code in the Play Scala application (2.5x, 2.11.11), which so far works very simply (it is based on the following link: https://fizzylogic.nl/2016/11/27/authorize-access-to-your -play-application-using-action-builders-and-action-functions / ). But now I need to pass another instance of the class to the ApplicationAuthorizationHandler class (NOTE: in all my code I use Guice DI to enter parameters into class constructors).

Current Code:

class ApplicationAuthorizationHandler
   extends AuthorizationHandler {
...
}

trait AuthorizationHandler {
...
}

trait AuthorizationCheck {
   def authorizationHandler: AuthorizationHandler = new ApplicationAuthorizationHandler

   object AuthenticatedAction extends ActionBuilder[RequestWithPrincipal] {
      override def invokeBlock[A](request: Request[A], block: (RequestWithPrincipal[A]) => Future[Result]): Future[Result] = {
         def unauthorizedAction = authorizationHandler.unauthorized(RequestWithOptionalPrincipal(None, request))
         def authorizedAction(principal: Principal) = block(RequestWithPrincipal(principal, request))

         authorizationHandler.principal(request).fold(unauthorizedAction)(authorizedAction)
      }
  }
}

//Example controller using this trait AuthorizationCheck
class MyController @Inject() extends Controller with AuthorizationCheck {
    def myAction = AuthenticatedAction { implicit request =>
...
}

Required Code:

class ApplicationAuthorizationHandler @Inject() (userService: UserService)
   extends AuthorizationHandler {
   ...
   // userService is used here
}

ApplicationAuthorizationHandler AuthorizationCheck, UserService. , , ( ). -, /? , , ApplicationAuthorizationHandler AuthorizationCheck ? ?

+1
2

, - :

trait AuthorizationHandler {
  ...
}

class ApplicationAuthorizationHandler extends AuthorizationHandler {
  ...
}

trait AuthorizationCheck {

  // just declaring that implementations needs to provide a 
  def authorizationHandler: AuthorizationHandler 

  object AuthenticatedAction extends ActionBuilder[RequestWithPrincipal] {
    override def invokeBlock[A](request: Request[A], block: (RequestWithPrincipal[A]) => Future[Result]): Future[Result] = {
      def unauthorizedAction = authorizationHandler.unauthorized(RequestWithOptionalPrincipal(None, request))
      def authorizedAction(principal: Principal) = block(RequestWithPrincipal(principal, request))

      authorizationHandler.principal(request).fold(unauthorizedAction)(authorizedAction)
    }
  }
}

// So, now this controller needs to provide a concrete implementation 
// of "authorizationHandler" as declared by "AuthorizationCheck".
// You can do it by injecting a "AuthorizationHandler" as a val with
// name authorizationHandler.
class MyController @Inject()(val authorizationHandler: AuthorizationHandler) extends Controller with AuthorizationCheck {

   def myAction = AuthenticatedAction { implicit request =>
     ...
   }
}

, , AuthorizationHandler ApplicationAuthorizationHandler:

import play.api.inject._

class AuthorizationHandlerModule extends SimpleModule(
  bind[AuthorizationHandler].to[ApplicationAuthorizationHandler]
)

, ApplicationAuthorizationHandler . .

+1

, @Inject. , , .

, , ,

object Injector {
  val injector = Guice.createInjector(new ProjectModule())
}

, . ( ).

, , ,

trait Foo {
   lazy val userService = Injector.injector.getInstance(classOf[UserService])
}

, , , .

0

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