Megatest

  (port #f)
  (uuid #f)
  (rep  #f)
  (dbfile #f)
  (api-url #f)
  (api-uri #f)
  (api-req #f)
  (uconn   #f) ;; this is the listener
  (mode    #f)
  (status 'starting)
  (trynum 0) ;; count the number of ports we've tried
  ) 

(define (servdat->url sdat)
  (conc (servdat-host sdat)":"(servdat-port sdat)))

  (let* ((fullname (db:dbname->path apath dbname))
	 (conn     (hash-table-ref/default (remotedat-conns remdat) fullname #f)))
    (if (and conn
	     (< (current-seconds) (conndat-expires conn)))
	conn
	#f)))

(define (rmt:find-main-server uconn apath dbname)
  (let* ((pktsdir     (get-pkts-dir apath))
	 (all-srvpkts (get-all-server-pkts pktsdir *srvpktspec*))
	 ;; (dbpath      (conc apath "/" dbname))
	 (viable-srvs (get-viable-servers all-srvpkts dbname)))
    (get-the-server uconn apath viable-srvs)))


(define *connstart-mutex* (make-mutex))
(define *last-main-start* 0)

;; looks for a connection to main, returns if have and not exired
;; creates new otherwise

      #;(if (conndat-socket conn)
	  (nng-close! (conndat-socket conn))) ;; TODO - close the ulex server here?
      (hash-table-set! conns fullpath #f) ;; clean up
      (rmt:open-main-connection remdat apath))
     (else
      ;; Below we will find or create and connect to main
      (let* ((dbname         (db:run-id->dbname #f))
	     (the-srv        (rmt:find-main-server myconn apath dbname))
	     (start-main-srv (lambda () ;; call IF there is no the-srv found
			       (mutex-lock! *connstart-mutex*)
			       (if (> (- (current-seconds) *last-main-start*) 5) ;; at least four seconds since last attempt to start main server
				   (begin
				     (api:run-server-process apath dbname)
				     (set! *last-main-start* (current-seconds))
				     (thread-sleep! 1)))

      (let* ((uconn (servdat-uconn *server-info*)))
	(wait-and-close uconn))
      (let* ((port            (portlogger:open-run-close portlogger:find-port))
	     (handler-proc    (lambda (rem-host-port qrykey cmd params) ;;
				(api:execute-requests *dbstruct-db* cmd params))))
	;; (api:process-request *dbstuct-db* 
	(set! *server-info* (make-servdat host: hostn port: port))
	(let* ((uconn (run-listener handler-proc port))
	       (rport (udat-port uconn))) ;; the real port
	  (servdat-host-set! *server-info* hostn)
	  (servdat-port-set! *server-info* rport)
	  (servdat-uconn-set! *server-info* uconn)
	  (wait-and-close uconn)
	  (db:print-current-query-stats)
	  )))

	   (read-pkt->alist pkt-file pktspec: pktspec))
	 all-pkt-files)))

(define (server-address srv-pkt)
  (conc (alist-ref 'host srv-pkt) ":"
	(alist-ref 'port srv-pkt)))
	
(define (server-ready? uconn host port key) ;; server-address is host:port
  (let* ((data (sexpr->string  `((cmd . ping)
				 (key . ,key)
				 (params . ()))))
	 (res  (send-receive uconn (conc host ":" port) 'ping data)))
    (if res
	(string->sexpr res)
	res)))

; from the pkts return servers associated with dbpath
;; NOTE: Only one can be alive - have to check on each
;;       in the list of pkts returned
;;
(define (get-viable-servers serv-pkts dbpath)
  (let loop ((tail serv-pkts)
	     (res  '()))
    (if (null? tail)
	res ;; NOTE: sort by age so oldest is considered first
	(let* ((spkt (car tail)))
	  (loop (cdr tail)
		(if (equal? dbpath (alist-ref 'dbpath spkt))
		    (cons spkt res)
		    res))))))

(define (remove-pkts-if-not-alive uconn serv-pkts)
  (filter (lambda (pkt)
	    (let* ((host (alist-ref 'host pkt))
		   (port (alist-ref 'port pkt))
		   (key  (alist-ref 'servkey  pkt))
		   (pktz (alist-ref 'Z        pkt))
		   (res  (server-ready? uconn host port key)))
	      (if res
		  res
		  (let* ((pktsdir (get-pkts-dir *toppath*))
			 (pktpath (conc pktsdir"/"pktz".pkt")))
		    (debug:print 0 *default-log-port* "WARNING: pkt with no server "pktpath)
		    (delete-file* pktpath)
		    #f))))
	  serv-pkts))

;; from viable servers get one that is alive and ready
;;
(define (get-the-server uconn apath serv-pkts)
  (let loop ((tail serv-pkts))
    (if (null? tail)
	#f
	(let* ((spkt  (car tail))
	       (host  (alist-ref 'ipaddr spkt))
	       (port  (alist-ref 'port spkt))
	       (dbpth (alist-ref 'dbpath spkt))
	       (srvkey (alist-ref 'Z spkt)) ;; (alist-ref 'srvkey spkt))
	       (addr  (server-address spkt)))
	  (if (server-ready? uconn host port srvkey)
	      spkt
	      (loop (cdr tail)))))))

;; am I the "first" in line server? I.e. my D card is smallest
;; use Z card as tie breaker
;;
(define (get-best-candidate serv-pkts dbpath)

	(debug:print-info 0 *default-log-port* "Waiting for server alive signature")
	(mutex-lock! *heartbeat-mutex*)
	(set! sdat *server-info*)
	(mutex-unlock! *heartbeat-mutex*)
	(if (and sdat
		 (not changed)
		 (> (- (current-seconds) start-time) 2))
	    (let* ((uconn (servdat-uconn sdat)))
	      (servdat-status-set! sdat 'iface-stable)
	      (debug:print-info 0 *default-log-port* "Received server alive signature, now attempting to lock in server")
	      ;; create a server pkt in *toppath*/.meta/srvpkts
	      
	      ;; TODO:
	      ;;   1. change sdat to stuct
	      ;;   2. add uuid to struct
	      ;;   3. update uuid in sdat here
	      ;;
	      (servdat-uuid-set! sdat
				 (register-server
				  pkts-dir *srvpktspec*
				  (get-host-name)
				  (servdat-port sdat) server-key
				  (servdat-host sdat) db-file))
	      ;; (set! *my-signature* (servdat-uuid sdat)) ;; replace with Z, no, stick with proper key
	      ;; now read pkts and see if we are a contender
	      (let* ((all-pkts     (get-all-server-pkts pkts-dir *srvpktspec*))
		     (viables      (get-viable-servers all-pkts db-file))
		     (alive        (remove-pkts-if-not-alive uconn viables))
		     (best-srv     (get-best-candidate alive db-file))
		     (best-srv-key (if best-srv (alist-ref 'servkey best-srv) #f))
		     (i-am-srv     (equal? best-srv-key server-key))
		     (delete-pkt   (lambda ()
				     (let* ((pktfile (conc (get-pkts-dir *toppath*)
							 "/" (servdat-uuid *server-info*)
							 ".pkt")))