EvolutionsComponents在编译时依赖注入游戏项目中

Question

我试图了解如何使用编译时DI运行演变.

import play.api.ApplicationLoader.Context
import play.api.cache.EhCacheComponents
import play.api.mvc.EssentialFilter
import play.api.routing.Router
import play.api._
import play.api.db.evolutions.{ DynamicEvolutions, EvolutionsComponents}
import play.filters.gzip.GzipFilter
import router.Routes

class AppLoader extends ApplicationLoader  {
  override def load(context: Context): Application = {
    LoggerConfigurator(context.environment.classLoader).foreach(_.configure(context.environment))
    new AppComponents(context).application
  }


}

class AppComponents(context: Context) extends BuiltInComponentsFromContext(context) with EhCacheComponents with EvolutionsComponents {

  lazy val applicationController = new controllers.Application(defaultCacheApi)
  lazy val usersController = new controllers.Users(defaultCacheApi)
  lazy val assets = new controllers.Assets(httpErrorHandler)

  applicationEvolutions

  // Routes is a generated class
  override def router: Router = new Routes(httpErrorHandler, applicationController, usersController, assets)

  val gzipFilter = new GzipFilter(shouldGzip =
    (request, response) => {
      val contentType = response.header.headers.get("Content-Type")
      contentType.exists(_.startsWith("text/html")) || request.path.endsWith("jsroutes.js")
    })

  override lazy val httpFilters: Seq[EssentialFilter] = Seq(gzipFilter)


}

但我一直得到错误错误:(19,7)类AppComponents需要是抽象的,因为类型=> play.api.db.DBApi的trait EvolutionsComponents中的方法dbApi未定义类AppComponents(context:Context)扩展BuiltInComponentsFromContext(context使用带有EvolutionsComponents的EhCacheComponents

我是斯卡拉的新手.

Answer 1

dbApi来自这个DBComponents特性,所以你的AppComponents课程也需要扩展DBComponents.您还需要扩展HikariCPComponents连接池.

class AppComponents(context: Context) extends BuiltInComponentsFromContext(context)
  with EhCacheComponents
  with EvolutionsComponents
  with DBComponents
  with HikariCPComponents {

请务必将evolutions和jdbc依赖项添加到您的build.sbt文件中.