Megatest

(use format typed-records) ;; RADT => purpose of json format??

(declare (unit rmt))
(declare (uses api))
(declare (uses http-transport))
(include "common_records.scm")
(declare (uses rmtmod))

(import rmtmod)

;;
;; THESE ARE ALL CALLED ON THE CLIENT SIDE!!!
;;

;; generate entries for ~/.megatestrc with the following
;;

  ;; 2. check the age of the connections. refresh the connection if it is older than timeout-20 seconds.
  ;; 3. do the query, if on homehost use local access
  ;;
  (let* ((start-time    (current-seconds)) ;; snapshot time so all use cases get same value
         (areapath      *toppath*);; TODO - resolve from dbstruct to be compatible with multiple areas
	 (runremote     (or area-dat
			    *runremote*))
	 (readonly-mode (if (and runremote
	 (readonly-mode (rmtmod:calc-ro-mode runremote *toppath*)))
				 (remote-ro-mode-checked runremote))
			    (remote-ro-mode runremote)
			    (let* ((dbfile  (conc *toppath* "/megatest.db"))
				   (ro-mode (not (file-write-access? dbfile)))) ;; TODO: use dbstruct or runremote to figure this out in future
			      (if runremote
				  (begin
				    (remote-ro-mode-set! runremote ro-mode)
				    (remote-ro-mode-checked-set! runremote #t)
				    ro-mode)
				  ro-mode)))))

    ;; DOT INIT_RUNREMOTE; // leaving off - doesn't really add to the clarity
    ;; DOT MUTEXLOCK -> INIT_RUNREMOTE [label="no remote?"];
    ;; DOT INIT_RUNREMOTE -> MUTEXLOCK;
    ;; ensure we have a record for our connection for given area
    (if (not runremote)                   ;; can remove this one. should never get here.         
	(begin

      (rmt:open-qry-close-locally cmd 0 params)
      )

     ;;DOT CASE3 [label="write in\nread-only mode"];
     ;;DOT MUTEXLOCK -> CASE3 [label="readonly\nmode?"]; {rank=same "case 3" CASE3}
     ;;DOT CASE3 -> "#f";
     ;; readonly mode, write request.  Do nothing, return #f
     (readonly-mode
     (readonly-mode (extras-readonly-mode *rmt-mutex* *default-log-port* cmd params))
      (mutex-unlock! *rmt-mutex*)
      (debug:print-info 12 *default-log-port* "rmt:send-receive, case 3")
      (debug:print 0 *default-log-port* "WARNING: write transaction requested on a readonly area.  cmd="cmd" params="params)
      #f)

     ;; This block was for pre-emptively resetting the connection if there had been no communication for some time.
     ;; I don't think it adds any value. If the server is not there, just fail and start a new connection.
     ;; also, the expire-time calculation might not be correct. We want, time-since-last-server-access > (server:get-timeout)
     ;;
     ;;DOT CASE4 [label="reset\nconnection"];
     ;;DOT MUTEXLOCK -> CASE4 [label="have connection,\nlast_access > expire_time"]; {rank=same "case 4" CASE4}

      (rmt:open-qry-close-locally cmd (if rid rid 0) params))

     ;;DOT CASE11 [label="send_receive"];
     ;;DOT MUTEXLOCK -> CASE11 [label="else"]; {rank=same "case 11" CASE11};
     ;;DOT CASE11 -> "rmt:send-receive" [label="call failed"];
     ;;DOT CASE11 -> "RESULT" [label="call succeeded"];
     ;; not on homehost, do server query
     (else
      ;; (mutex-unlock! *rmt-mutex*)
      (debug:print-info 12 *default-log-port* "rmt:send-receive, case  9")
      ;; (mutex-lock! *rmt-mutex*)
      (let* ((conninfo (remote-conndat runremote))
	     (dat      (case (remote-transport runremote)
			 ((http) (condition-case ;; handling here has caused a lot of problems. However it is needed to deal with attemtped communication to servers that have gone away
                                  (http-transport:client-api-send-receive 0 conninfo cmd params)
                                  ((commfail)(vector #f "communications fail"))
                                  ((exn)(vector #f "other fail" (print-call-chain)))))
			 (else
			  (debug:print 0 *default-log-port* "ERROR: transport " (remote-transport runremote) " not supported")
			  (exit))))
	     (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)
              (http-transport:close-connections  area-dat: runremote)))
	;; (mutex-unlock! *rmt-mutex*)
        (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
	    (if (and (vector? res)
		     (eq? (vector-length res) 2)
		     (eq? (vector-ref res 1) 'overloaded)) ;; since we are looking at the data to carry the error we'll use a fairly obtuse combo to minimise the chances of some sort of collision.
                ;; this is the case where the returned data is bad or the 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
	    (begin
	      (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")
	      ;; (if (not (server:check-if-running *toppath*))
	      ;; 	  (server:start-and-wait *toppath*))
	      (rmt:send-receive cmd rid params attemptnum: (+ attemptnum 1)))))))))

     (else (extras-case-11 *default-log-port* runremote cmd params attemptnum)))))
    ;;DOT }
    

;; bunch of small functions factored out of send-receive to make debug easier
;;

(define (extras-case-11 *default-log-port* runremote cmd params attemptnum)
  ;; (mutex-unlock! *rmt-mutex*)
  (debug:print-info 12 *default-log-port* "rmt:send-receive, case  9")
  ;; (mutex-lock! *rmt-mutex*)
  (let* ((conninfo (remote-conndat runremote))
	 (dat      (case (remote-transport runremote)
		     ((http) (condition-case ;; handling here has
					     ;; caused a lot of
					     ;; problems. However it
					     ;; is needed to deal with
					     ;; attemtped
					     ;; communication to
					     ;; servers that have gone
					     ;; away
			      (http-transport:client-api-send-receive 0 conninfo cmd params)
			      ((commfail)(vector #f "communications fail"))
			      ((exn)(vector #f "other fail" (print-call-chain)))))
		     (else
		      (debug:print 0 *default-log-port* "ERROR: transport " (remote-transport runremote) " not supported")
		      (exit))))
	 (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)
	(extras-transport-failed *default-log-port* *rmt-mutex* attemptnum runremote cmd rid params)
	)))

;; (define (rmt:update-db-stats run-id rawcmd params duration)
;;   (mutex-lock! *db-stats-mutex*)
;;   (handle-exceptions
;;    exn
;;    (begin
;;      (debug:print 0 *default-log-port* "WARNING: stats collection failed in update-db-stats")
;;      (debug:print 0 *default-log-port* " message: " ((condition-property-accessor 'exn 'message) exn))

  (rmt:send-receive 'archive-register-disk #f (list bdisk-name bdisk-path df)))

(define (rmt:test-set-archive-block-id run-id test-id archive-block-id)
  (rmt:send-receive 'test-set-archive-block-id run-id (list run-id test-id archive-block-id)))

(define (rmt:test-get-archive-block-info archive-block-id)
  (rmt:send-receive 'test-get-archive-block-info #f (list archive-block-id)))

(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)