Megatest

  (let* ((start-port      (portlogger:open-run-close portlogger:find-port))
	 (server-thread   (make-thread (lambda ()
					 (nmsg-transport:try-start-server dbstruct run-id start-port server-id))
				       "server thread"))
	 (tdbdat          (tasks:open-db)))
    (thread-start! server-thread)
    (if (nmsg-transport:ping hostn start-port timeout: 2 expected-key: (current-process-id))
	(let ((interface (if (equal? hostn "-")(get-host-name) hostn)))
	  (tasks:server-set-interface-port (db:delay-if-busy tdbdat) server-id interface start-port)
	  (tasks:server-set-state! (db:delay-if-busy tdbdat) server-id "dbprep")
	  (set! *server-info* (list hostn start-port)) ;; probably not needed anymore? currently used by keep-running
	  (thread-sleep! 3) ;; give some margin for queries to complete before switching from file based access to server based access
	  (set! *inmemdb*  dbstruct)
	  (tasks:server-set-state! (db:delay-if-busy tdbdat) server-id "running")
	  (thread-start! (make-thread
			  (lambda ()(nmsg-transport:keep-running server-id))

		    (begin
		      (debug:print-info 0 "Another server took the slot, exiting")
		      (exit 0))))
	      (begin
		;; since we didn't get the server lock we are going to clean up and bail out
		(debug:print-info 2 "INFO: server pid=" (current-process-id) ", hostname=" (get-host-name) " not starting due to other candidates ahead in start queue")
		(tasks:server-delete-records-for-this-pid (db:delay-if-busy tdbdat) " http-transport:launch")
		))
	  ;; locked in a server id, try to start up
	  (nmsg-transport:run dbstruct hostn run-id server-id))
      (set! *didsomething* #t)
      (exit))))

;;======================================================================
;; S E R V E R   U T I L I T I E S 
;;======================================================================

;;======================================================================

;; ping the server at host:port
;;   return the open socket if successful (return-socket == #t)
;;   expect the key expected-key returned in payload
;;   send our-key or #f as payload
;;
(define (nmsg-transport:ping hostn port #!key (timeout 3)(return-socket #t)(expected-key #f)(our-key #f)(socket #f))
  ;; send a random number along with pid and check that we get it back
  (let* ((req     (or socket (nn-socket 'req)))
	 (host    (if (or (not hostn)
			  (equal? hostn "-")) ;; use localhost
		      (get-host-name)
		      hostn))
	 (success #f)
	 (keepwaiting #t)
	 (dat     (db:obj->string (vector "ping" our-key) transport: 'nmsg))

				   (if (and keepwaiting (< count timeout)) ;; yes, this is very aproximate
				       (loop (+ count 1))))
				 (if keepwaiting
				     (begin
				       (print "timeout waiting for ping")
				       (thread-terminate! ping))))
			       "timeout")))
    (if (not socket)(nn-connect req (conc "tcp://" host ":" port)))
    (handle-exceptions
     exn
     (begin
       ;; (print-call-chain)
       ;; (print 0 " message: " ((condition-property-accessor 'exn 'message) exn))
       ;; (print "exn=" (condition->list exn))
       (debug:print-info 1 "ping failed to connect to " host ":" port))
     (thread-start! timeout)
     (thread-start! ping)
     (thread-join! ping)
     (if success (thread-terminate! timeout)))
    (if return-socket
	(if success req #f)
	(begin
	  (nn-close req) ;; should it be closed if we were handed a socket?
	  success))))


















;; run nmsg-transport:keep-running in a parallel thread to monitor that the db is being 
;; used and to shutdown after sometime if it is not.
;;
(define (nmsg-transport:keep-running server-id)
  ;; if none running or if > 20 seconds since 
  ;; server last used then start shutdown
  ;; This thread waits for the server to come alive

              (debug:print-info 0 "Starting to shutdown the server.")
              (set! *time-to-exit* #t)
              (tasks:server-delete-record (db:delay-if-busy tdbdat) server-id " http-transport:keep-running")
              (debug:print-info 0 "Server shutdown complete. Exiting")
              ;; (exit)
	      ))))))

;;======================================================================
;; C L I E N T S
;;======================================================================

(define (nmsg-transport:client-connect iface portnum)
  (let* ((reqsoc      (nmsg-transport:ping iface portnum return-socket: #t)))
    (vector iface portnum #f #f #f (current-seconds) reqsoc)))

(define (nmsg-transport:client-api-send-receive run-id connection-info cmd param)
  (let ((packet  (vector cmd param))
	(reqsoc  (http-transport:server-dat-get-socket connection-info)))
    (nn-send reqsoc (db:obj->string packet transport: 'nmsg))
    (db:string->obj (nn-recv reqsoc) transport: 'nmsg)))

;;======================================================================
;; J U N K 
;;======================================================================

;; DO NOT USE
;;
(define (nmsg-transport:client-signal-handler signum)
  (handle-exceptions
   exn
   (debug:print " ... exiting ...")
   (let ((th1 (make-thread (lambda ()
			     (if (not *received-response*)
				 (receive-message* *runremote*))) ;; flush out last call if applicable