Megatest

;;======================================================================
;;  S U P P O R T   F U N C T I O N S
;;======================================================================

;; if a server is either running or in the process of starting call client:setup
;; else return #f to let the calling proc know that there is no server available
;;
(define (rmt:get-connection-info areapath #!key (area-dat #f)) ;; TODO: push areapath down.
  (let* ((runremote (or area-dat *runremote*))
	 (cinfo     (if (remote? runremote)
			(remote-conndat runremote)
			#f)))
	  (if cinfo
	      cinfo
	      (if (server:check-if-running areapath)
		  (client:setup areapath)
		  #f))))

     ;; reset the connection if it has been unused too long
     ((and runremote
           (remote-conndat runremote)
	   (> (current-seconds) ;; if it has been more than server-timeout seconds since last contact, close this connection and start a new on
	      (+ (http-transport:server-dat-get-last-access (remote-conndat runremote))
		 (remote-server-timeout runremote))))
      (debug:print-info 0 *default-log-port* "Connection to " (remote-server-url runremote) " expired due to no accesses, forcing new connection.")


      (remote-conndat-set! runremote #f) ;; invalidate the connection, thus forcing a new connection.
      (http-transport:close-connections area-dat: runremote)
      (mutex-unlock! *rmt-mutex*)
      (rmt:send-receive cmd rid params attemptnum: attemptnum))
     
     ;;DOT CASE5 [label="local\nread"];
     ;;DOT MUTEXLOCK -> CASE5 [label="server not required,\non homehost,\nread-only query"]; {rank=same "case 5" CASE5};
     ;;DOT CASE5 -> "rmt:open-qry-close-locally";

	       (not (remote-conndat runremote)))
	  (and (not (cdr (remote-hh-dat runremote)))        ;; not on a homehost 
	       (not (remote-conndat runremote))))           ;; and no connection
      (debug:print-info 12 *default-log-port* "rmt:send-receive, case 9, hh-dat: " (remote-hh-dat runremote) " conndat: " (remote-conndat runremote))
      (mutex-unlock! *rmt-mutex*)
      (if (not (server:check-if-running *toppath*)) ;; who knows, maybe one has started up?
	  (server:start-and-wait *toppath*))
      (remote-conndat-set! runremote (rmt:get-connection-info *toppath*)) ;; calls client:setup which calls client:setup-http
      (rmt:send-receive cmd rid params attemptnum: attemptnum)) ;; TODO: add back-off timeout as

     ;;DOT CASE10 [label="on homehost"];
     ;;DOT MUTEXLOCK -> CASE10 [label="server not required,\non homehost"]; {rank=same "case 10" CASE10};
     ;;DOT CASE10 -> "rmt:open-qry-close-locally";
     ;; all set up if get this far, dispatch the query
     ((and (not (remote-force-server runremote))

	 (success  (if (vector? dat) (vector-ref dat 0) #f))
	 (res      (if (vector? dat) (vector-ref dat 1) #f)))
    (if (and (vector? conninfo) (< 5 (vector-length conninfo)))
	(http-transport:server-dat-update-last-access conninfo) ;; refresh access time
	(begin
	  (debug:print 0 *default-log-port* "INFO: Should not get here! conninfo=" conninfo)
	  (set! conninfo #f)
	  (remote-conndat-set! *runremote* #f) ;; NOTE: *runremote* is global copy of runremote. Purpose: factor out global.
	  (http-transport:close-connections  area-dat: runremote)))
    (debug:print-info 13 *default-log-port* "rmt:send-receive, case  9. conninfo=" conninfo " dat=" dat " runremote = " runremote)
    (mutex-unlock! *rmt-mutex*)
    (if success ;; success only tells us that the transport was
	;; successful, have to examine the data to see if
	;; there was a detected issue at the other end
	(extras-transport-succeded *default-log-port* *rmt-mutex* attemptnum runremote res params rid cmd)
	(begin

  (debug:print-info 12 log-port "rmt:send-receive, case 3")
  (debug:print 0 log-port "WARNING: write transaction requested on a readonly area.  cmd="cmd" params="params)
  #f)

(define (extras-transport-failed *default-log-port* *rmt-mutex* attemptnum runremote cmd rid params)
  (debug:print 0 *default-log-port* "WARNING: communication failed. Trying again, try num: " attemptnum)
  (mutex-lock! *rmt-mutex*)
  (remote-conndat-set!    runremote #f)
  (http-transport:close-connections area-dat: runremote)
  (remote-server-url-set! runremote #f)
  (mutex-unlock! *rmt-mutex*)
  (debug:print-info 12 *default-log-port* "rmt:send-receive, case  9.1")
  (rmt:send-receive cmd rid params attemptnum: (+ attemptnum 1)))
  
(define (extras-transport-succeded *default-log-port* *rmt-mutex* attemptnum runremote res params rid cmd)
  (if (and (vector? res)

						 ;; server is
						 ;; overloaded and we
						 ;; want to ease off
						 ;; the queries
      (let ((wait-delay (+ attemptnum (* attemptnum 10))))
	(debug:print 0 *default-log-port* "WARNING: server is overloaded. Delaying " wait-delay " seconds and trying call again.")
	(mutex-lock! *rmt-mutex*)
	(http-transport:close-connections area-dat: runremote)
	(set! *runremote* #f) ;; force starting over
	(mutex-unlock! *rmt-mutex*)
	(thread-sleep! wait-delay)
	(rmt:send-receive cmd rid params attemptnum: (+ attemptnum 1)))
      res)) ;; All good, return res

#;(set-functions rmt:send-receive                       remote-server-url-set!
	       http-transport:close-connections	      remote-conndat-set!
	       debug:print                            debug:print-info
	       remote-ro-mode                         remote-ro-mode-set!
	       remote-ro-mode-checked-set!            remote-ro-mode-checked)