code_projects_kotlin/STEP1_Basics/9_Network/Main.kt

package org.server

import com.beust.klaxon.Klaxon
import java.io.BufferedReader
import java.io.InputStreamReader
import java.io.PrintWriter
import java.net.ServerSocket

data class Person(
    val name: String,
    val age: Int,
    val city: String
)

const val serverPort: Int = 12345

fun main() {
    val server = ServerSocket(serverPort)
    println("Server started on port $serverPort...")

    while (true) {
        val client = server.accept()
        println("Client connected: ${client.inetAddress.hostAddress}:${client.port}")

        val reader = BufferedReader(InputStreamReader(client.getInputStream()))
        val writer = PrintWriter(client.getOutputStream(), true)

        val rawReceived = reader.readLine()
        //println("Received from client: $received")
        val json = Klaxon().parse<Person>(rawReceived)
        println("""
            
            Parsed data:
            name: ${json?.name}
            age: ${json?.age}
            city: ${json?.city}
            
        """.trimIndent())

        val response = "OK"
        writer.println(response)

        client.close()
    }
}