WSClient - Too Many Open Files

Question

I'm working with Play Framework 2.4 on CentOS 6 and my application is throwing this exception:

java.net.SocketException: Too many open files

I've searched a lot of topics on Stack Overflow and tried the solutions:

• Increase the number of open files to 65535;
• Change hard and soft limits on /etc/security/limits.conf;
• Change the value of fs.file-max on /etc/sysctl.conf;
• Reduced the timeout on file /proc/sys/net/ipv4/tcp_fin_timeout;

The error keeps happening. On another sites, i've found people that are facing the same problem because they weren't calling the method close() from WSClient but in my case, i'm working with dependency injection:

@Singleton
class RabbitService @Inject()(ws:WSClient) {

  def myFunction() {
    ws.url(“url”).withHeaders(
      "Content-type" -> "application/json",
      "Authorization" -> ("Bearer " + authorization))
      .post(message)
      .map(r => {
      r.status match {
        case 201 => Logger.debug("It Rocks")
        case _ => Logger.error(s"It sucks")
      }
    })

  }

}

If i change my implementation to await the result, it work's like a charm but the performance is very poor - and i would like to use map function instead wait the result:

@Singleton
class RabbitService @Inject()(ws:WSClient) {

  def myFunction() {
    val response = ws.url("url")
      .withHeaders(
        "Content-type" -> "application/json",
        "Authorization" -> ("Bearer " + authorization))
      .post(message)

    Try(Await.result(response, 1 seconds)) match {
      case Success(r) =>
        if(r.status == 201) {
          Logger.debug(s"It rocks")
        } else {
          Logger.error(s"It sucks")
        }
      case Failure(e) => Logger.error(e.getMessage, e)
    }

  }

}

Anyone have an idea how can i fix this error? I've tried everything but without success.

Answer 1

If anyone is facing the same problem, you need to configure WSClient on application.conf - need to set maxConnectionsTotal and maxConnectionsPerHost.

This is how I solved this problem.

https://www.playframework.com/documentation/2.5.x/ScalaWS