val response = window.fetch(url, object: RequestInit {
        override var method: String? = method
        override var body: dynamic = body
        override var credentials: RequestCredentials? = RequestCredentials.Companion.INCLUDE
        override var cache: RequestCache? = RequestCache.Companion.NO_CACHE
        override var mode: RequestMode? = RequestMode.Companion.NO_CORS
        override var headers: dynamic = json("Accept" to "application/json")
      }).await()

override var headers

override var headers: dynamic = json("User-Id" to "ewfwefwe")

kotlin-fullstack-sample

require 'socket'
s = TCPServer.new 8080

loop do
    c = s.accept    # Wait for a client to connect
    while line = c.gets # Read lines from socket
        puts line         # and print them
    end
end

fetch