Starting a Vertx web server and handler

vertx.clj

(defmethod ig/init-key ::http-server
  [_ {:keys [vertx port]}]
  (let [server
        (..
         vertx
         (createHttpServer
          (..
           (new HttpServerOptions)
           (setPort port))))]
    (..
     server
     (requestHandler
      (reify Handler
        (handle [_ event]
          (..
           event
           response
           (setChunked true)
           (setStatusCode 200)
           (write "Hello World!")
           end))))
     listen)))