Question

你好，我想在Scala AKKA MySql中实现sql语句，该语句使用Slick.source连接到MySQL数据库，我想在具有特定时间段的计时器中执行查询。我想在10秒钟内从数据库中获取信息，但我没有找到有关如何执行此操作的任何信息。我的问题是：在Slick中是否可以使用SQL语句实现计时器的任何选项。知道吗??

class AKKAMYSQL {
  def run(connectionMysql: Config,mqttUrlSub:String,mqttUserSub:String,mqttPasswordSub:String,mqttTopicSub:String): Unit = {
print(" AKKAMYSQL ")
implicit val system = ActorSystem()
implicit val mat = ActorMaterializer()

val configFile = new File("application.conf")
val fileConfig = ConfigFactory.parseFile(configFile)
val config = ConfigFactory.load(fileConfig)

val sinkSettingsInflux = MqttConnectionSettings(
  mqttUrlSub,
  "",
  new MemoryPersistence
).withAuth(mqttUserSub, mqttPasswordSub)

implicit val session = SlickSession.forConfig(connectionMysql)
system.registerOnTermination(session.close())
case class User(plant: String,source: String,value:String,timeStamp:String,tipo: String)
implicit val getUserResult = GetResult(r => User(r.nextString(), r.nextString(),r.nextString(),r.nextString(),r.nextString()))
import session.profile.api._
val done: Future[Done] =
  Slick.source(sql"SELECT plantnodes.xid as planta,profilesources.xid as profileSource,profilevalues.value as value,profilevalues.ts as timeStamp,profiletypes.xid as tipo FROM profileheaders  INNER JOIN profilevalues ON profilevalues.profileHeaderId = profileheaders.id INNER JOIN plantnodes ON plantnodes.id = profileheaders.plantNodeId INNER JOIN profilesources ON profilesources.id = profileheaders.profileSourceId INNER JOIN profiletypes ON profiletypes.id = profileheaders.profileTypeId WHERE profiletypes.xid = 'RTV#FR#00'  OR profiletypes.xid = 'RTV#CAVG#00' OR profiletypes.xid = 'RTV#AP#00' OR profiletypes.xid = 'RTV#RP#00' OR 'RTV#SP#00' OR 'RTV#PF#00' OR 'RTV#VAVG#00' OR 'RTV#SOC#00' OR 'RTV#TH#00' LIMIT 3".as[User])
  .via(Flow[User].map(f = u => {
    val jsonString =
      """
{
}
    val json: JsValue = Json.parse(jsonString)
    new MqttMessage(topic =mqttTopicSub,ByteString.apply(Json.stringify(res)))
  }))
    .log("user")
    .runWith(Sink.ignore)

done.onComplete {end => {
  if (end.isFailure) {
    println("Error  " + end.get.toString())
    System.exit(1)
  }
  else
    println("Finished")
}

}


}
}

Answer 1

我不认为slick具有所需的功能。但是，您可以使用其他akka构造来实现相同的目标。

首先，构造一个执行您的SQL查询的Actor：

object Tick

class TickActor(akkamysql : AKKAMYSQL) extends Actor {
  override def receive : Receive = {
    case Tick => akkamysql.run()
  }
}

然后，将此Actor与ActorSystem的Scheduler结合使用：

val akkamysql : AKKAMYSQL = ???

val actorSystem : ActorSystem = ???

val tickActorRef = actorSystem.actorOf(Props(classOf[TickActor], akkamysql))

import system.dispatcher

val cancellable = 
  system.scheduler.schedule(0 milliseconds, 10000 milliseconds, tickActor, Tick)

在Akka中实现计时器

1 个答案: