播放WS standalone for 2.5.x.

Question

我想在Play应用程序之外创建一个Play Web服务客户端.对于Play WS版本2.4.x,很容易发现它是这样完成的:

val config = new NingAsyncHttpClientConfigBuilder().build()
val builder = new AsyncHttpClientConfig.Builder(config)
val client = new NingWSClient(builder.build)

但是在2.5.x中,NingWSClient现在已经弃用了 - 而AhcWSClient应该使用它.

不幸的是,我没有找到一个完整的例子来解释Play之外的AhcWsClient的创建和使用.目前我跟这个:

import play.api.libs.ws.ahc.AhcWSClient
import akka.stream.ActorMaterializer
import akka.actor.ActorSystem

implicit val system = ActorSystem()
implicit val materializer = ActorMaterializer()
val ws = AhcWSClient()

val req = ws.url("http://example.com").get().map{
  resp => resp.body
}(system.dispatcher)

这是创建一个正确的方法AhcWsClient吗？有没有办法创造一个AhcWSClient没有ActorSystem？

Answer 1

您可能正在使用编译时依赖注入,否则您只需使用@Inject() (ws: WSClient),对吧？
文档中有一个示例:https://www.playframework.com/documentation/2.5.x/ScalaWS#using-wsclient
因此您可以在应用程序加载器中编写类似的内容:

lazy val ws = {
  import com.typesafe.config.ConfigFactory
  import play.api._
  import play.api.libs.ws._
  import play.api.libs.ws.ahc.{AhcWSClient, AhcWSClientConfig}
  import play.api.libs.ws.ahc.AhcConfigBuilder
  import org.asynchttpclient.AsyncHttpClientConfig

  val configuration = Configuration.reference ++ Configuration(ConfigFactory.parseString(
    """
      |ws.followRedirects = true
    """.stripMargin))

  val parser = new WSConfigParser(configuration, environment)
  val config = new AhcWSClientConfig(wsClientConfig = parser.parse())
  val builder = new AhcConfigBuilder(config)
  val logging = new AsyncHttpClientConfig.AdditionalChannelInitializer() {
    override def initChannel(channel: io.netty.channel.Channel): Unit = {
      channel.pipeline.addFirst("log", new io.netty.handler.logging.LoggingHandler("debug"))
    }
  }
  val ahcBuilder = builder.configure()
  ahcBuilder.setHttpAdditionalChannelInitializer(logging)
  val ahcConfig = ahcBuilder.build()
  new AhcWSClient(ahcConfig)
}
applicationLifecycle.addStopHook(() => Future.successful(ws.close))

然后注入ws您的控制器.我不是100%肯定这种方法,如果有一些Play大师可以验证这一点,我会很高兴.
关于a ActorSystem,你只需要获得一个线程池来解决它Future.您也可以导入或注入默认执行上下文:
play.api.libs.concurrent.Execution.Implicits.defaultContext.
或者你可以使用自己的:
implicit val wsContext: ExecutionContext = actorSystem.dispatchers.lookup("contexts.your-special-ws-config").