Megatest

(define *server-loop-heart-beat* (current-seconds))
(define *heartbeat-mutex* (make-mutex))

;;======================================================================
;; S E R V E R
;;======================================================================

(define (nmsg-transport:run dbstruct hostn run-id server-id #!key (retrynum 1000))
  (debug:print 2 "Attempting to start the server ...")
  (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))
			  "keep running"))
	  (thread-join! server-thread))
	(if (> retrynum 0)
	    (begin
	      (debug:print 0 "WARNING: Failed to connect to server (self) on host " hostn ":" start-port ", trying again.")
	      (tasks:server-delete-record (db:delay-if-busy tdbdat) server-id "failed to start, never received server alive signature")
	      (portlogger:open-run-close portlogger:set-failed start-port)
	      (nmsg-transport:run dbstruct hostn run-id server-id))
	    (begin
	      (debug:print 0 "ERROR: could not find an open port to start server on. Giving up")
	      (exit 1))))))

(define (nmsg-transport:try-start-server dbstruct run-id portnum server-id)
  (let ((repsoc (nn-socket 'rep)))
    (nn-bind repsoc (conc "tcp://*:" portnum))
    (let loop ((msg-in (nn-recv repsoc)))
      (cond
       ((equal? msg-in "quit")

;; 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* ((host    (if (or (not hostn)
			  (equal? hostn "-")) ;; use localhost
		      (get-host-name)
		      hostn))
	 (req     (or socket
		      (let ((soc (nn-socket 'req)))
			(nn-connect soc (conc "tcp://" host ":" port))
			soc)))
	 (dat     (db:obj->string (vector "ping" our-key) transport: 'nmsg))
	 (result  (nmsg-transport:client-api-send-receive-raw req dat timeout: timeout))

	 (success (vector-ref result 0))
	 (key     (if success 
		      (vector-ref (db:string->obj (vector-ref result 1) transport: 'nmsg) 1)
		      #f)))
    (debug:print 0 "success=" success ", key=" key ", expected-key=" expected-key ", equal? " (equal? key expected-key))
    (if (and success
	     (or (not expected-key) ;; just getting a reply is good enough then
		 (equal? key expected-key)))
	(if return-socket
	    req
	    (begin

	      (if (not socket)(nn-close req)) ;; don't want a side effect of closing socket if handed it
	      #t))
	(begin
	  (if (not socket)(nn-close req)) ;; failed to ping, close socket as side effect
	  #f))))

;; send data to server, wait max of timeout seconds for a response.
;; return #( success/fail result )
;;
(define (nmsg-transport:client-api-send-receive-raw socreq dat #!key (timeout 5))
  (let* ((success     #f)
	 (result      #f)
	 (keepwaiting #t)
	 (send-recv   (make-thread
		       (lambda ()
			 (nn-send socreq dat)
			 (let* ((res (nn-recv socreq)))
			   (set! success #t)
			   (set! result res)))
		       "send-recv"))
	 (timeout     (make-thread
		       (lambda ()
			 (let loop ((count 0))
			   (thread-sleep! 1)
			   (debug:print-info 1 "send-receive-raw, still waiting after " count " seconds...")
			   (if (and keepwaiting (< count timeout)) ;; yes, this is very aproximate
			       (loop (+ count 1))))
			 (if keepwaiting
			     (begin
			       (print "timeout waiting for ping")
			       (thread-terminate! send-recv))))
		       "timeout")))

    (handle-exceptions
     exn



     (set! result "timeout")

     (thread-start! timeout)
     (thread-start! send-recv)
     (thread-join! send-recv)
     (if success (thread-terminate! timeout)))

    (vector success result)))




;; 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

;; 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)))

;; return #( success result )
;;
(define (nmsg-transport:client-api-send-receive run-id connection-info cmd param #!key (remtries 5))
  (mutex-lock! *http-mutex*)
  (let* ((packet  (db:obj->string (vector cmd param) transport: 'nmsg))
	 (reqsoc  (http-transport:server-dat-get-socket connection-info))
	 (rawres  (nmsg-transport:client-api-send-receive-raw reqsoc packet))

	 (status  (vector-ref rawres 0))
	 (result  (vector-ref rawres 1)))
    (mutex-unlock! *http-mutex*)

    (vector status (if status (db:string->obj result transport: 'nmsg) result))))
	
;;======================================================================
;; J U N K 
;;======================================================================

;; DO NOT USE
;;
(define (nmsg-transport:client-signal-handler signum)