Megatest

    ;;===============================================
    ;; READ/WRITE QUERIES
    ;;===============================================

    ((get-keys-write)                        (db:get-keys dbstruct)) ;; force a dummy "write" query to force server; for debug in -repl
    
    ;; SERVERS
    ((start-server)                    (apply server:kind-run params))
    ((start-server)                    (apply tt:server-process-run params))
    ((kill-server)                     (set! *server-run* #f))

    ;; TESTS

    ;;((test-set-state-status-by-id)     (apply mt:test-set-state-status-by-id dbstruct params))
    ;;BB - commented out above because it was calling below, eventually, incorrectly (dbstruct passed to mt:test-set-state-status-by-id, which previosly did more, but now only passes thru to db:set-state-status-and-roll-up-items.
    ((test-set-state-status-by-id)

(define *transport-type*    'http)             ;; override with [server] transport http|rpc|nmsg
(define *runremote*         #f)                ;; if set up for server communication this will hold <host port>
;; (define *max-cache-size*    0)
(define *logged-in-clients* (make-hash-table))
(define *server-id*         #f)
(define *server-info*       #f)  ;; good candidate for easily convert to non-global
(define *time-to-exit*      #f)
(define *server-run*        #t)
(define *run-id*            #f)
(define *server-kind-run*   (make-hash-table))
(define *home-host*         #f)
;; (define *total-non-write-delay* 0)
(define *heartbeat-mutex*   (make-mutex))
;; (define *api-process-request-count* 0)
;; (define *max-api-process-requests* 0)

;;======================================================================

(define *send-receive-mutex* (make-mutex)) ;; should have separate mutex per run-id

;; how to make area-dat
(define (rmt:set-ttdat areapath ttdat)
  (if (not ttdat)
  (if ttdat
      ttdat
      (let* ((newremote  (make-and-init-remote areapath)))
	(set! *ttdat* newremote)
	ttdat)))
	newremote)))

;; NB// area-dat replaced by ttdat
;; 
(define (rmt:send-receive cmd run-id params #!key (attemptnum 1)(ttdat #f))
  (assert *toppath* "FATAL: rmt:send-receive called with *toppath* not set.")
  (assert ttdat     "FATAL: rmt:send-receive must receive initialized area-dat")
  (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
         (attemptnum    (+ 1 attemptnum))
	 (readonly-mode (rmtmod:calc-ro-mode ttdat *toppath*))
	 (testsuite     (common:get-testsuite-name))
	 (mtexe         (common:find-local-megatest))
	 (dbfname       (conc (dbfile:run-id->dbnum run-id)".db")))
    (rmt:set-ttdat areapath ttdat)
    (tt:handler (rmt:set-ttdat ttdat) cmd run-id params
		attemptnum readonly-mode dbfname
		testsuite mtexe)))
	 (dbfname       (conc (dbfile:run-id->dbnum run-id)".db"))
	 (ttdat         (rmt:set-ttdat areapath ttdat))
	 (conn          (tt:get-conn ttdat dbfname))
	 (is-main       (equal? dbfname "main.db")) ;; why not (not run-id) ?
	 (server-start-proc (if is-main
				#f
				(lambda ()
				  ;; (debug:print-info 0 *default-log-port* "starting server for dbfname: "dbfname)
				  (rmt:start-server ;; tt:server-process-run
				   areapath
				   testsuite ;; (dbfile:testsuite-name)
				   mtexe
				   run-id)))))
    ;; here we look at ttdat, if dbfname is NOT main.db we check that a conn exists for it
    ;; and if there is no conn we first send a request to the main.db server to start a
    ;; server for the dbfname.
    #;(if (and (not is-main)(not conn)) ;; no existing connection to non-main server, call in a start up request
	(begin
	  (server-start-proc)
	  (thread-sleep! 1)))
    (tt:handler ttdat cmd run-id params attemptnum readonly-mode dbfname testsuite mtexe server-start-proc)))

;; KEEP THIS HERE FOR A WHILE, WE MAY WANT TO RESURECT IT
;; (define (nfs-transport-handler  runremote cmd run-id params attemptnum area-dat areapath readonly-mode testsuite mtexe)
;;   (let* ((keys     (common:get-fields *configdat*))
;; 	 (dbstruct (dbmod:nfs-get-dbstruct run-id keys (dbfile:db-init-proc) areapath tmpadj: "/dashboard")))
;;     (api:dispatch-request dbstruct cmd run-id params)))
	

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

(define (rmt:kill-server run-id)
  (rmt:send-receive 'kill-server run-id (list run-id)))

(define (rmt:start-server run-id)
  (rmt:send-receive 'start-server 0 (list run-id)))
(define (rmt:start-server areapath testsuite mtexe run-id) ;; run on main.db server
  (rmt:send-receive 'start-server #f (list areapath testsuite mtexe run-id)))

;;======================================================================
;;  M I S C
;;======================================================================

(define (rmt:login run-id)
  (rmt:send-receive 'login run-id (list *toppath* megatest-version (client:get-signature))))

;; This login does no retries under the hood - it acts a bit like a ping.
;; Deprecated for nmsg-transport.
;;
;; (define (rmt:login-no-auto-client-setup runremote)
;;   (rmt:send-receive-no-auto-client-setup runremote 'login 0 (list *toppath* megatest-version (client:get-signature))))
;;   (rmt:send-receive-no-auto-client-setup runremote 'login #f (list *toppath* megatest-version (client:get-signature))))


;; given a hostname, return a pair of cpu load and update time representing latest intelligence from tests running on that host
(define (rmt:get-latest-host-load hostname)
  (rmt:send-receive 'get-latest-host-load 0 (list hostname)))
  (rmt:send-receive 'get-latest-host-load #f (list hostname)))

(define (rmt:sdb-qry qry val run-id)
  ;; add caching if qry is 'getid or 'getstr
  (rmt:send-receive 'sdb-qry run-id (list qry val)))

;; NOT COMPLETED
(define (rmt:runtests user run-id testpatt params)

;; parameters
;;
(define tt-server-timeout-param (make-parameter 600))

;; make ttdat visible
(define *server-info* #f)
(define *server-run*  #t)

(define (tt:make-remote areapath)
  (make-tt areapath: areapath))

;; 1 ... or #f
;; and check that dbfname matches. FIXME: the propagation of dbfname and run-id
;; might not make the best sense
;;
(define (tt:valid-run-id run-id dbfname)
  (and (or (number? run-id)
	   (not run-id))
       (equal? (dbfile:run-id->dbfname run-id) dbfname)))

(tcp-buffer-size 2048)
;; (max-connections 4096) 
;; (max-connections 4096)

(define (tt:get-conn ttdat dbfname)
  (hash-table-ref/default (tt-conns ttdat) dbfname #f))

;; do all the busy work of finding and setting up conn for
;; connecting to a server
;; 
(define (tt:client-connect-to-server ttdat dbfname run-id testsuite)
(define (tt:client-connect-to-server ttdat dbfname run-id testsuite server-start-proc)
  (assert (tt:valid-run-id run-id dbfname) "FATAL: invalid run-id "run-id)
  (debug:print-info 2 *default-log-port* "tt:client-connect-to-server " dbfname " " run-id)
  (let* ((conn (hash-table-ref/default (tt-conns ttdat) dbfname #f))
	 (server-start-proc (lambda ()
			      (print "dbfname: "dbfname)
			      (assert (equal? dbfname "main.db") ;; only main.db is started here
				      "FATAL: called server-start-proc for db other than main.db")
			      (tt:server-process-run
			       (tt-areapath ttdat)
			       testsuite ;; (dbfile:testsuite-name)
			       (common:find-local-megatest)
			       run-id))
  (let* ((conn              (tt:get-conn ttdat dbfname))
	 (server-start-proc (or server-start-proc
				(lambda ()
				  (assert (equal? dbfname "main.db") ;; only main.db is started here
					  "FATAL: called server-start-proc for db other than main.db")
				  (tt:server-process-run
				   (tt-areapath ttdat)
				   testsuite ;; (dbfile:testsuite-name)
				   (common:find-local-megatest)
				   run-id)))))
			    ))
    (if conn
	(begin 
          (debug:print-info 2 *default-log-port* "already connected to a server")
           conn) ;; we are already connected to the server
	(let* ((sdat (tt:get-current-server-info ttdat dbfname)))
	  (match sdat
	    ((host port start-time server-id pid dbfname2 servinffile)

		   ((running)
                    (debug:print-info 2 *default-log-port* "Setting conn = " conn " in hash table")
		    (hash-table-set! (tt-conns ttdat) dbfname conn) ;;; is this ok to save before validating that the connection is good?
		    conn)
		   ((starting)
		    (thread-sleep! 0.5)
                    (debug:print-info 0 *default-log-port* "server for " dbfname " is in starting state, retrying connect")
		    (tt:client-connect-to-server ttdat dbfname run-id testsuite))
		    (tt:client-connect-to-server ttdat dbfname run-id testsuite server-start-proc))
		   (else
		    (let* ((curr-secs (current-seconds)))
		      ;; rm the (last server) would go here
		      (if (> (- curr-secs (tt-last-serv-start ttdat)) 10)
			  (begin
			    (tt-last-serv-start-set! ttdat curr-secs)
			    (server-start-proc))) ;; start server if 10 sec since last attempt
		      (thread-sleep! 1)
                      (debug:print-info 2 *default-log-port* "server ping result was neither running nor starting. Retrying connect")
		      (tt:client-connect-to-server ttdat dbfname run-id testsuite)))))))
		      (tt:client-connect-to-server ttdat dbfname run-id testsuite server-start-proc)))))))
	    (else ;; no good server found, if haven't started server in > 5 secs, start another
	     (if (> (- (current-seconds) (tt-last-serv-start ttdat)) 3) ;; BUG - grow this number really do not want to swamp the machine with servers
		 (begin
		   (debug:print-info 0 *default-log-port* "Starting server for "dbfname)
		   (server-start-proc)
		   (tt-last-serv-start-set! ttdat (current-seconds))
                   (thread-sleep! 3)
                   ))
	     (thread-sleep! 1)
             (debug:print-info 0 *default-log-port* "Connect to server for " dbfname)
	     (tt:client-connect-to-server ttdat dbfname run-id testsuite)))))))
	     (tt:client-connect-to-server ttdat dbfname run-id testsuite server-start-proc)))))))

(define (tt:timed-ping host port server-id)
  (let* ((start-time (current-milliseconds))
	 (result     (tt:ping host port server-id)))
    (cons result (- (current-milliseconds) start-time))))
    

       ;; (debug:print 0 *default-log-port* "res not in form (status errmsg result meta), got: "res)
       (try-again)))))

;; client side handler
;;
;;(tt:handler #<tt> get-keys #f () 2 #f "/home/matt/data/megatest/ext-tests" #f "main.db" "ext-tests" "/home/matt/data/megatest/bin/.22.04/../megatest")
;;
(define (tt:handler ttdat cmd run-id params attemptnum readonly-mode dbfname testsuite mtexe)
(define (tt:handler ttdat cmd run-id params attemptnum readonly-mode dbfname testsuite mtexe server-start-proc)
  ;; connect-to-server will start a server if needed.
  (let* ((areapath (tt-areapath ttdat))
	 (conn     (tt:client-connect-to-server ttdat dbfname run-id testsuite))) ;; looks up conn keyed by dbfname
	 (conn     (tt:client-connect-to-server ttdat dbfname run-id testsuite server-start-proc))) ;; looks up conn keyed by dbfname
    (if conn
	;; have connection, call the server
	(let* ((res (tt:send-receive ttdat conn cmd run-id params)))
	  ;; res is (status errmsg result meta)
	  (match res
	    ((status errmsg result meta)
	     (if (list? meta)

    (tt:create-server-registration-file ttdat dbfname)
    ;; now start watching the last-access, if it hasn't been touched
    ;; in over ten seconds we exit
    (thread-sleep! 0.05) ;; any real need for delay here?
    (let loop ()
      (let* ((servers (tt:get-server-info-sorted ttdat dbfname))
	     (ok      (cond
		       ((not *server-run*)
			(debug:print 0 *default-log-port* "WARNING: received a stop server from client by remote request.")
			#f)
		       ((null? servers) #f) ;; not ok
		       ((equal? (list-ref (car servers) 6) ;; compare the servinfofile
				(tt-servinf-file ttdat))
			(let* ((res (if db-locked-in
					#t
					(let* ((lock-result  ;; this is the primary lock - need to double verify that got it
						(dbfile:with-no-sync-db

	      (cleanup)
	      (exit)))

	(let* ((last-update (dbr:dbstruct-last-update dbstruct))
	       (curr-secs   (current-seconds)))
	  (if (and (eq? (tt-state ttdat) 'running)
		   (> (- curr-secs last-update) 3)) ;; every 3-4 seconds update the db?
	      (begin
		(set! (file-modification-time (tt-servinf-file ttdat)) (current-seconds))
	      (let* ((sinfo-file (tt-servinf-file ttdat)))
		;; (debug:print 0 *default-log-port* "INFO: touching "sinfo-file)
		(set! (file-modification-time sinfo-file) (current-seconds))
		((dbr:dbstruct-sync-proc dbstruct) last-update)
		(dbr:dbstruct-last-update-set! dbstruct curr-secs))))
	  
	(if (< (- (current-seconds) (tt-last-access ttdat)) (tt-server-timeout-param))
	    (begin
	      (thread-sleep! 5)
	      (loop)))))

;; find valid server
;; get servers listed, last part of name must match :<dbfname>
;; if more than one, wait one second and look again
;; future: ping oldest, if alive remove other :<dbfname> files
;;
(define (tt:find-server areapath dbfname)
  (let* ((servdir  (tt:get-servinfo-dir areapath))
	 (sfiles   (glob (conc servdir"/*:"dbfname))))
    
	 (sfiles   (glob (conc servdir"/*:"dbfname)))
	 (goodfiles '()))

    ;; filter the files here by looking in processes table (if we are not main.db)
    ;; and or look at the time stamp on the servinfo file, a running server will
    ;; touch the file every minute (again, this will only apply for main.db)
    
    sfiles))
    (for-each (lambda (fname)
		(let* ((age (- (current-seconds)(file-modification-time fname))))
		  (if (> age 10) ;; can't trust it if over ten seconds old
		      (begin
			(debug:print 0 *default-log-port* "WARNING: removing stale servinfo file "fname)
			(delete-file fname))
		      (set! goodfiles (cons fname goodfiles)))))
	      sfiles)
    goodfiles))

;; given a path to a server info file return: host port startseconds server-id pid dbfname logf
;; example of what it's looking for in the log file:
;;     SERVER STARTED: 10.38.175.67:50216 AT 1616502350.0 server-id: 4907e90fc55c7a09694e3f658c639cf4 
;;
(define (tt:server-get-info logf)
  (let ((server-rx    (regexp "^SERVER STARTED: (\\S+):(\\d+) AT ([\\d\\.]+) server-id: (\\S+) pid: (\\d+) dbfname: (\\S+)")) ;; SERVER STARTED: host:port AT timesecs server id

			    (string->number pid)
			    dbfname
			    logf))
		     (else
		      (debug:print 0 *default-log-port* "ERROR: did not recognise SERVER line info "mlst)
		      bad-dat)))))))))

(define *last-server-start* (make-hash-table))

(define (tt:too-recent-server-start dbfname)
  (let* ((last-run-time (hash-table-ref/default *last-server-start* dbfname #f)))
    (and last-run-time
	 (< (- (current-seconds) last-run-time) 5))))
    
;; Given an area path,  start a server process    ### NOTE ### > file 2>&1 
;; if the target-host is set 
;; try running on that host
;;   incidental: rotate logs in logs/ dir.
;;
(define  (tt:server-process-run areapath testsuite mtexe run-id #!key (profile-mode "")) ;; areapath is *toppath* for a given testsuite area
  (assert areapath  "FATAL: tt:server-process-run called without areapath defined.")
  (assert testsuite "FATAL: tt:server-process-run called without testsuite defined.")
  (assert mtexe     "FATAL: tt:server-process-run called without mtexe defined.")
  ;; mtest -server - -m testsuite:ext-tests -db 6.db
  (let* ((dbfname  (dbmod:run-id->dbfname run-id))
	 (load     (get-normalized-cpu-load))
	 (srvrs    (tt:find-server areapath dbfname))
	 (trying   (length srvrs))
	 (nrun     (number-of-processes-running (conc "mtest.*server.*"testsuite".*"dbfname))))
    (cond
     ((> load 2.0)
      (debug:print 0 *default-log-port* "Normalized load "load" on " (get-host-name) " is over the limit of 2.0. Not starting a server. Please reduce the load on "(get-host-name)" by killing some processes")
      (thread-sleep! 1)
      #f)
     ((> nrun 100)
      (debug:print 0 *default-log-port* nrun" servers running on " (get-host-name) ", not starting another.")
      (thread-sleep! 1)
      #f)
     ((> trying 2)
      (debug:print 0 *default-log-port* trying" servers registered in .servinfo dir. not starting another.")
      (thread-sleep! 1)
      #f)
     (else
      (if (not (file-exists? (conc areapath"/logs")))
	      (create-directory (conc areapath"/logs") #t))
	  (let* ((logfile   (conc areapath "/logs/server-"dbfname"-"(current-process-id)".log")) ;; -" curr-pid "-" target-host ".log"))
		 (cmdln     (conc
			     mtexe
			     " -startdir "areapath
			     " -server - ";; (or target-host "-")
			     " -m testsuite:"testsuite
			     " -db "dbfname ;; (dbmod:run-id->dbfname run-id)
			     " " profile-mode
			     (conc " >> " logfile " 2>&1 &"))))
	    ;; we want the remote server to start in *toppath* so push there
	    ;; (push-directory areapath) ;; use cd in the command line instead
	    (debug:print 2 *default-log-port* "INFO: Trying to start server in tcp mode (" cmdln ") at "(common:human-time)" for "areapath)
	    ;; (debug:print 0 *default-log-port* "INFO: starting server at " (common:human-time))
  (let* ((dbfname  (dbmod:run-id->dbfname run-id)))
    (if (tt:too-recent-server-start dbfname)
	#f
	(let* ((load     (get-normalized-cpu-load))
	       (srvrs    (tt:find-server areapath dbfname))
	       (trying   (length srvrs))
	       (nrun     (number-of-processes-running (conc "mtest.*server.*"testsuite".*"dbfname))))
	  (cond
	   ((> load 2.0)
	    (debug:print 0 *default-log-port* "Normalized load "load" on " (get-host-name) " is over the limit of 2.0. Not starting a server. Please reduce the load on "(get-host-name)" by killing some processes")
	    (thread-sleep! 1)
	    #f)
	   ((> nrun 100)
	    (debug:print 0 *default-log-port* nrun" servers running on " (get-host-name) ", not starting another.")
	    (thread-sleep! 1)
	    #f)
	   ((> trying 2)
	    (debug:print 0 *default-log-port* trying" servers registered in .servinfo dir. not starting another.")
	    (thread-sleep! 1)
	    #f)
	   (else
	    (if (not (file-exists? (conc areapath"/logs")))
		(create-directory (conc areapath"/logs") #t))
	    (let* ((logfile   (conc areapath "/logs/server-"dbfname"-"(current-process-id)".log")) ;; -" curr-pid "-" target-host ".log"))
		   (cmdln     (conc
			       mtexe
			       " -startdir "areapath
			       " -server - ";; (or target-host "-")
			       " -m testsuite:"testsuite
			       " -db "dbfname ;; (dbmod:run-id->dbfname run-id)
			       " " profile-mode
			       (conc " >> " logfile " 2>&1 &"))))
	      ;; we want the remote server to start in *toppath* so push there
	      ;; (push-directory areapath) ;; use cd in the command line instead
	      (debug:print 2 *default-log-port* "INFO: Trying to start server in tcp mode (" cmdln ") at "(common:human-time)" for "areapath)
	      ;; (debug:print 0 *default-log-port* "INFO: starting server at " (common:human-time))

	    (system cmdln)
	    ;; ;; use below to go back to nbfake - nbfake does cause trouble ...
	    ;; (setenv "NBFAKE_QUIET" "yes") ;; BUG: change to with-environment-variable ...
	    ;; (setenv "NBFAKE_LOG" logfile)
	    ;; (system (conc "cd "areapath" ; nbfake " cmdln))
	    ;; (unsetenv "NBFAKE_QUIET")
	    ;; (unsetenv "NBFAKE_LOG")
	    
	    ;;(pop-directory)
	    #t)))))
	      (system cmdln)
	      (hash-table-set! *last-server-start* dbfname (current-seconds))
	      ;; ;; use below to go back to nbfake - nbfake does cause trouble ...
	      ;; (setenv "NBFAKE_QUIET" "yes") ;; BUG: change to with-environment-variable ...
	      ;; (setenv "NBFAKE_LOG" logfile)
	      ;; (system (conc "cd "areapath" ; nbfake " cmdln))
	      ;; (unsetenv "NBFAKE_QUIET")
	      ;; (unsetenv "NBFAKE_LOG")
	      
	      ;;(pop-directory)
	      #t)))))))

;;======================================================================
;; tcp connection stuff
;;======================================================================

;; find a port and start tcp-server. This only starts the tcp portion of
;; the server, look at (tt:start-server ...) above for the entry point