IllegalArgumentException: Neither port nor sslPort specified.

For Ktor 1.0.0 server, java version 1.8.0_181 (running server on localhost, Ubuntu 18.04.1 LTS)

Facing the following issue:

Exception in thread "main" java.lang.IllegalArgumentException: Neither port nor sslPort specified. Use command line options -port/-sslPort or configure connectors in application.conf
	at io.ktor.server.engine.CommandLineKt$commandLineEnvironment$environment$1.invoke(CommandLine.kt:121)
	at io.ktor.server.engine.CommandLineKt$commandLineEnvironment$environment$1.invoke(CommandLine.kt)
	at io.ktor.server.engine.ApplicationEngineEnvironmentBuilder.build(ApplicationEngineEnvironment.kt:95)
	at io.ktor.server.engine.ApplicationEngineEnvironmentKt.applicationEngineEnvironment(ApplicationEngineEnvironment.kt:40)
	at io.ktor.server.engine.CommandLineKt.commandLineEnvironment(CommandLine.kt:50)
	at io.ktor.server.netty.EngineMain.main(EngineMain.kt:16)
	at com.gurpreetsk.ApplicationKt.main(Application.kt:36)

However, the application.conf file contains the following:

ktor {
  deployment {
    port = 8080
    port = ${?PORT}
  }
  application {
    modules = [ com.gurpreetsk.ApplicationKt.module ]
  }
}

[piritus]

There was the same problem after the update of the IDE, it helped “Sync Project with Gradle Files”

[cy6erGn0m]

That’s quite strange that you have orange test and out directories. For sure something is misconfigured.

application.conf should be in out directory, like this:

I’ve just tried to create a project using ktor plugin and it runs just fine in IDEA and via gradle as well. Same for website https://start.ktor.io