Megatest

(define (tasks:hostinfo-get-port        vec)    (vector-ref  vec 2))
(define (tasks:hostinfo-get-pubport     vec)    (vector-ref  vec 3))
(define (tasks:hostinfo-get-transport   vec)    (vector-ref  vec 4))
(define (tasks:hostinfo-get-pid         vec)    (vector-ref  vec 5))
(define (tasks:hostinfo-get-hostname    vec)    (vector-ref  vec 6))

(define (tasks:server-lock-slot mdb run-id)
  (let ((res '())
	(best #f))
    (tasks:server-clean-out-old-records-for-run-id mdb run-id)


    (tasks:server-set-available mdb run-id)
    (thread-sleep! 2) ;; Try removing this. It may not be needed.
    (tasks:server-am-i-the-server? mdb run-id)))

	
;; register that this server may come online (first to register goes though with the process)
(define (tasks:server-set-available mdb run-id)
  (sqlite3:execute 
   mdb 
   "INSERT INTO servers (pid,hostname,port,pubport,start_time,      priority,state,mt_version,heartbeat,   interface,transport,run_id)
                   VALUES(?, ?,       ?,   ?, strftime('%s','now'), ?,       ?,    ?, strftime('%s','now'),?,        ?,        ?);"
   (current-process-id)       ;; pid
   (get-host-name)            ;; hostname
   -1                         ;; port
   -1                         ;; pubport
   (random 1000)              ;; priority (used a tiebreaker on get-available)
   "available"                ;; state
   (common:version-signature) ;; mt_version
   -1                         ;; interface
   "http"                     ;; transport
   run-id
   ))











(define (tasks:server-clean-out-old-records-for-run-id mdb run-id)
  (sqlite3:execute mdb "DELETE FROM servers WHERE state in ('available','shutting-down') AND (strftime('%s','now') - start_time) > 30 AND run_id=?;" run-id)


  (sqlite3:execute mdb "DELETE FROM servers WHERE state='running' AND (strftime('%s','now') - heartbeat)  > 10 AND run_id=?;" run-id)
  )
  



(define (tasks:server-set-state! mdb server-id state)
  (sqlite3:execute mdb "UPDATE servers SET state=? WHERE id=?;" state server-id))

(define (tasks:server-delete-record! mdb server-id)
  (sqlite3:execute mdb "DELETE FROM servers WHERE id=?;" server-id))

(define (tasks:server-delete-records-for-this-pid mdb)
  (sqlite3:execute mdb "DELETE FROM servers WHERE hostname=? AND pid=?;" (get-host-name) (current-process-id)))

(define (tasks:server-set-interface-port mdb server-id interface port)
  (sqlite3:execute mdb "UPDATE servers SET interface=?,port=? WHERE id=?;" interface port server-id))
























(define (tasks:server-am-i-the-server? mdb run-id)
  (let* ((all    (tasks:server-get-servers-vying-for-run-id mdb run-id))
	 (first  (if (null? all)
		     (begin (debug:print 0 "ERROR: no servers listed, should be at least one by now.") 
			    (sqlite3:finalize! mdb)
			    (exit 1))
		     (car (db:get-rows all))))

     (lambda (a . b)
       (set! res (cons (apply vector a b) res)))
     mdb
     (conc "SELECT " selstr " FROM servers WHERE run_id=? ORDER BY start_time DESC;")
     run-id)
    (vector header res)))

(define (tasks:server-update-heartbeat mdb server-id)
  (debug:print-info 1 "Heart beat update of server id=" server-id)
  (handle-exceptions
   exn
   (begin
     (debug:print 0 "WARNING: probable timeout on monitor.db access")
     (thread-sleep! 1)
     (tasks:server-update-heartbeat mdb server-id))
   (sqlite3:execute mdb "UPDATE servers SET heartbeat=strftime('%s','now') WHERE id=?;" server-id)))

;; alive servers keep the heartbeat field upto date with seconds every 6 or so seconds
(define (tasks:server-alive? mdb server-id #!key (iface #f)(hostname #f)(port #f)(pid #f))
  (let* ((server-id  (if server-id 
			 server-id
			 (tasks:server-get-server-id mdb hostname iface port pid)))
	 (heartbeat-delta 99e9))
    (sqlite3:for-each-row
     (lambda (delta)
       (set! heartbeat-delta delta))
     mdb "SELECT strftime('%s','now')-heartbeat FROM servers WHERE id=?;" server-id)
    (< heartbeat-delta 10)))

(define (tasks:get-server mdb run-id)
  (let ((res  #f)
	(best #f))
    (sqlite3:for-each-row
     (lambda (id interface port pubport transport pid hostname)
       (set! res (vector id interface port pubport transport pid hostname)))
     mdb


     "SELECT id,interface,port,pubport,transport,pid,hostname FROM servers
          WHERE strftime('%s','now')-heartbeat < 10 
          AND mt_version=? AND run_id=? AND state='running'
          ORDER BY start_time DESC LIMIT 1;" (common:version-signature) run-id)
    res))

;; (define (tasks:get-all-servers mdb)
;;   (let ((res  '()))
;;     (sqlite3:for-each-row
;;      (lambda (id interface port pubport transport pid hostname)
;;        (set! res (cons (vector id interface port pubport transport pid hostname) res)))
;;      mdb
;;      "SELECT id,interface,port,pubport,transport,pid,hostname FROM servers
;;           WHERE strftime('%s','now')-heartbeat < 10 
;;           AND mt_version=? 
;;           ORDER BY start_time DESC;" (common:version-signature))
;;     res))

(define (tasks:get-all-servers mdb)
  (let ((res '()))
    (sqlite3:for-each-row
     (lambda (id pid hostname interface port pubport start-time priority state mt-version last-update transport)
       (set! res (cons (vector id pid hostname interface port pubport start-time priority state mt-version last-update transport) res)))
     mdb
     "SELECT id,pid,hostname,interface,port,pubport,start_time,priority,state,mt_version,strftime('%s','now')-heartbeat AS last_update,transport FROM servers ORDER BY start_time DESC;")
    res))

(define (tasks:kill-server status hostname port pid transport)
  (debug:print-info 1 "Removing defunct server record for " hostname ":" port)
  (if port
      (open-run-close tasks:server-deregister tasks:open-db hostname port: port)
      (open-run-close tasks:server-deregister tasks:open-db hostname pid:  pid))
  (if status ;; #t means alive
      (begin
	(if (equal? hostname (get-host-name))
	    (handle-exceptions
	     exn
	     (debug:print-info 0 "server may or may not be dead, check for megatest -server running as pid " pid "\n"
			       "  EXCEPTION: " ((condition-property-accessor 'exn 'message) exn))
	     (debug:print 1 "Sending signal/term to " pid " on " hostname)
	     (process-signal pid signal/term)
	     (thread-sleep! 5) ;; give it five seconds to die peacefully then do a brutal kill
	     ;;(process-signal pid signal/kill)
	     ) ;; local machine, send sig term
	    (begin
	      ;;(debug:print-info 1 "Stopping remote servers not yet supported."))))
	      (debug:print-info 1 "Telling alive server on " hostname ":" port " to commit servercide")
	      (let ((serverdat (list hostname port)))
	      	(case (if (string? transport) (string->symbol transport) transport)
	      	  ((http)(http-transport:client-connect hostname port))
	      	  (else  (debug:print "ERROR: remote stopping servers of type " transport " not supported yet")))
	      	(cdb:kill-server serverdat pid)))))    ;; remote machine, try telling server to commit suicide
      (begin
	(if status 
	    (if (equal? hostname (get-host-name))
		(begin
		  (debug:print-info 1 "Sending signal/term to " pid " on " hostname)
		  (process-signal pid signal/term)  ;; local machine, send sig term