Megatest

            tcp-transportmod.scm

all : $(PREFIX)/bin/.$(ARCHSTR) mtest dboard mtut tcmt

transport-mode.scm : transport-mode.scm.template
	cp transport-mode.scm.template transport-mode.scm

dashboard-transport-mode.scm : transport-mode.scm.template
	cp transport-mode.scm.template dashboard-transport-mode.scm

megatest.scm : transport-mode.scm
dashboard.scm : dashboard-transport-mode.scm

# dbmod.import.o is just a hack here
mofiles/dbfile.o     : mofiles/debugprint.o mofiles/commonmod.o dbmod.import.o
db.o : dbmod.import.o
mofiles/debugprint.o : mofiles/mtargs.o

# ftail.scm rmtmod.scm commonmod.scm removed

;; These are called by the server on recipt of /api calls
;;    - keep it simple, only return the actual result of the call, i.e. no meta info here
;;
;;    - returns #( flag result )
;;
(define (api:execute-requests dbstruct dat)
  (db:open-no-sync-db) ;; sets *no-sync-db*
  ;;   (handle-exceptions
  ;;    exn
  ;;    (let ((call-chain (get-call-chain)))
  ;;      (debug:print 0 *default-log-port* "WARNING: api:execute-requests received an exception from peer, dat=" dat ", exn=" exn)
  ;;      (print-call-chain (current-error-port))
  ;;      (debug:print 0 *default-log-port* " message: "  ((condition-property-accessor 'exn 'message) exn))       
  ;;      (vector #f (vector exn call-chain dat))) ;; return some stuff for debug if an exception happens
  (if (> *api-process-request-count* 200)
      (begin
	(if (common:low-noise-print 30 "too many threads")
	    (debug:print 0 *default-log-port* "WARNING: "*api-process-request-count*" threads, potential overload, adding 0.5 sec delay."))
	(thread-sleep! 0.5) ;; take a nap
	))
  (cond
   ((not (vector? dat))                    ;; it is an error to not receive a vector
    (vector #f (vector #f "remote must be called with a vector")))
   #;((> *api-process-request-count* 200) ;; 20)
   (debug:print 0 *default-log-port* "WARNING: api:execute-requests received an overloaded message.")
   (set! *server-overloaded* #t)
   (vector #f (vector #f 'overloaded))) ;; the inner vector is what gets returned. nope, don't know why. please refactor!
   (else  
    (let* ((cmd-in            (vector-ref dat 0))
           (cmd               (if (symbol? cmd-in)
				  cmd-in
				  (string->symbol cmd-in)))
           (params            (vector-ref dat 1))
	   (run-id            (if (null? params)
				  0
				  (car params)))
	   (write-mutex       (if (hash-table-exists? *db-write-mutexes* run-id)
				  (hash-table-ref *db-write-mutexes* run-id)
				  (let* ((newmutex (make-mutex)))
				    (hash-table-set! *db-write-mutexes* run-id newmutex)
				    newmutex)))
           (start-t           (current-milliseconds))
           (readonly-mode     (dbr:dbstruct-read-only dbstruct))
           (readonly-command  (member cmd api:read-only-queries))
           (writecmd-in-readonly-mode (and readonly-mode (not readonly-command))))
      (if (not readonly-command)
	  (mutex-lock! write-mutex))
      (let* ((tmppath    (dbr:dbstruct-tmppath  dbstruct))
	     (clean-run-id (cond
			    ((number? run-id)   run-id)
			    ((equal? run-id #f) "main")
			    (else               "other")))
	     (crumbfile  (dbfile:wait-for-qif tmppath clean-run-id (cons cmd params)))
	     (res    
              (if writecmd-in-readonly-mode
                  (conc "attempt to run write command "cmd" on a read-only database")
		  (api:dispatch-request dbstruct cmd run-id params))))
	(delete-file* crumbfile)
	(if (not readonly-command)
	    (mutex-unlock! write-mutex))
	
	;; save all stats
	(let ((delta-t (- (current-milliseconds)
			  start-t))
	      (modified-cmd (if (eq? cmd 'general-call)
				(string->symbol (conc "general-call-" (car params)))
				cmd)))
	  (hash-table-set! *db-api-call-time* modified-cmd
			   (cons delta-t (hash-table-ref/default *db-api-call-time* modified-cmd '()))))
	(if writecmd-in-readonly-mode
            (begin
              #;(common:telemetry-log (conc "api-out:"(->string cmd))
              payload: `((params . ,params)
              (ok-res . #t)))
	      (vector #f res))
            (begin
              #;(common:telemetry-log (conc "api-out:"(->string cmd))
              payload: `((params . ,params)
              (ok-res . #f)))
              (vector #t res))))))))

;; indat is (cmd run-id params meta)
;;
;; WARNING: Do not print anything in this function as it reads/writes to current in/out port
;;
(define (api:tcp-dispatch-request-make-handler dbstruct) ;; cmd run-id params)
  (lambda ()
    (let* ((indat (deserialize)))
      (set! *api-process-request-count* (+ *api-process-request-count* 1))
      (match indat
	((cmd run-id params meta)
	 (let* ((status  (cond
			  ;; turn off busy throttling while trying to get things stable
			  ;; ((> *api-process-request-count* 50) 'busy)
			  ;; ((> *api-process-request-count* 25) 'loaded)
			  (else 'ok)))
		(errmsg  (case status
			   ((busy)   (conc "Server overloaded, "*api-process-request-count*" threads in flight"))
			   ((loaded) (conc "Server loaded, "*api-process-request-count*" threads in flight"))
			   (else     #f)))
		(result  (case status
			   ((busy loaded) #f)
			   (else
			    (case cmd
			      ((ping) (tt:mk-signature *toppath*))
			      (else
			       (api:dispatch-request dbstruct cmd run-id params))))))
		(payload (list status errmsg result '())))
	   (set! *api-process-request-count* (- *api-process-request-count* 1))
	   (serialize payload)))
	(else
	 (assert #f "FATAL: failed to deserialize indat "indat))))))
       

(define (api:dispatch-request dbstruct cmd run-id params)
  (db:open-no-sync-db)
  (case cmd
    ;;===============================================
    ;; READ/WRITE QUERIES
    ;;===============================================

    ((get-keys-write)                        (db:get-keys dbstruct)) ;; force a dummy "write" query to force server; for debug in -repl
    

	      (lambda (dbdat db)
		(sqlite3:execute  (db:get-cache-stmth dbdat db "DELETE FROM metadat WHERE var=?;") var))))

;;======================================================================
;; no-sync.db - small bits of data to be shared between servers
;;======================================================================

(define (db:get-dbsync-path)
  (case (rmt:transport-mode)
    ((http)(common:get-db-tmp-area))
    ((tcp) (conc *toppath*"/.megatest"))
    ((nfs) (conc *toppath*"/.megatest"))
    (else "/tmp/dunno-this-gonna-exist")))

 ;; (define (db:no-sync-db db-in)
 ;;   (if db-in
 ;;       db-in
 ;;       (if *no-sync-db*
 ;; 	  *no-sync-db*
 ;; 	  (begin
 ;; 	    (mutex-lock! *db-access-mutex*)
 ;; 	    (let ((dbpath (db:get-dbsync-path))
 ;; 		  (db     (dbfile:open-no-sync-db dbpath)))
 ;; 	      (assert (sqlite3:database? db) "FATAL: db:no-sync-db failed to open a database")
 ;; 	      (set! *no-sync-db* db)
 ;; 	      (mutex-unlock! *db-access-mutex*)
 ;; 	      db)))))

(define (with-no-sync-db proc)
  (let* ((db  (db:open-no-sync-db)))
    (proc db)))

(define (db:open-no-sync-db)
  (dbfile:open-no-sync-db (db:get-dbsync-path)))

(define (db:no-sync-close-db db stmt-cache)
  (db:safely-close-sqlite3-db db stmt-cache))


;; use a global for some primitive caching, it is just silly to
;; re-read the db over and over again for the keys since they never

  (let* ((backupfname (conc fname"-"(current-process-id)".bak"))
	 (cmd (conc "cp "fname" "backupfname";mv "fname" "(conc fname ".delme;")
		    "cp "backupfname" "fname)))
    (dbfile:print-err "WARNING: attempting recovery of file "fname" by running commands:\n"
		      "  "cmd)
    (system cmd)))


(define (dbfile:open-no-sync-db dbpath)
  (if *no-sync-db*
      *no-sync-db*
      (begin
	(if (not (file-exists? dbpath))
	    (create-directory dbpath #t))
	(let* ((dbname    (conc dbpath "/no-sync.db"))
	       (db-exists (file-exists? dbname))
	       (init-proc (lambda (db)
			    (if (not db-exists)
				(begin
				  (sqlite3:execute db "CREATE TABLE IF NOT EXISTS no_sync_metadat (var TEXT,val TEXT, CONSTRAINT no_sync_metadat_constraint UNIQUE (var));"))
				)))
	       (on-tmp      (equal? (car (string-split dbpath "/")) "tmp"))
	       (db        (if on-tmp
			      (dbfile:cautious-open-database dbname init-proc 0 "WAL")
			      (sqlite3:open-database dbname))))
	  (if on-tmp	      ;; done in cautious-open-database
	      (begin
		(sqlite3:execute db "PRAGMA synchronous = 0;")
		(sqlite3:set-busy-handler! db (sqlite3:make-busy-timeout 136000))))
	  (set! *no-sync-db* db)
	  db))))

(define (db:no-sync-set db var val)
  (sqlite3:execute db "INSERT OR REPLACE INTO no_sync_metadat (var,val) VALUES (?,?);" var val))

(define (db:no-sync-del! db var)

   ((> attemptnum 20) (thread-sleep! 1)))

  ;; I'm turning this off, it may make sense to move it
  ;; into http-transport-handler
  (if (and (> attemptnum 5) (= 0 (modulo attemptnum 15)))  
      (begin
	(debug:print 0 *default-log-port* "ERROR: can't connect to server, trying to start a server.")
	(case (rmt:transport-mode)
	  ((http)
	   (server:run *toppath*)
	   (thread-sleep! 3))
	  (else
	   (thread-sleep! 1) ;; for tcp the server is started by routines in tcp-transportmod. For nfs there is no server
	   ))))
  
  ;; 1. check if server is started IFF cmd is a write OR if we are not on the homehost, store in runremote
  ;; 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

  ;; find oldest alive
  ;;   1. sort by age ascending and ping until good
  ;; find alive rand from youngest
  ;;   1. sort by age descending
  ;;   2. take five
  ;;   3. check alive, discard if not and repeat
  ;; first we clean up old server files
  (assert (eq? (rmt:transport-mode) 'http) "FATAL: server:run called with rmt:transport-mode="(rmt:transport-mode))
  (server:clean-up-old areapath)
  (let* ((since-last (- (current-seconds) server-last-start))
        (server-start-delay 10))     
    (if ( < (- (current-seconds) server-last-start) 10 )
      (begin
        (debug:print 2 *default-log-port* "server:choose-server: seconds since last server start: " (- (current-seconds) server-last-start))
        (debug:print 2 *default-log-port* "server:choose-server: last server start less than " server-start-delay " seconds ago. Sleeping " server-start-delay " seconds")

		 (debug:print 0 *default-log-port* "WARNING: failed to delete old server info file "sfile)
		 (delete-file sfile))))))
     sfiles)))

;; would like to eventually get rid of this
;;
(define (common:on-homehost?)
  (if (eq? (rmt:transport-mode) 'http)
      (server:choose-server *toppath* 'home?)
      #t)) ;; there is no homehost for tcp and nfs is always on home so #t should work

;; kind start up of server, wait before allowing another server for a given
;; area to be launched
;;
(define (server:kind-run areapath)
  ;; look for $MT_RUN_AREA_HOME/logs/server-start-last
  ;; and wait for it to be at least <server idletime> seconds old

  (thread       #f)
  (host-port    #f)
  (cmd-thread   #f)
  (ro-mode      #f)
  (ro-mode-checked #f)
  (last-access  (current-seconds))
  (servinf-file #f)
  (last-serv-start 0)
  )

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

;; do all the busy work of finding and setting up conn for
;; connecting to a server

			   server-id: server-id
			   server-start: start-time
			   pid: pid)))
	       (hash-table-set! (tt-conns ttdat) dbfname conn)
	       ;; verify we can talk to this server
	       (if (tt:ping host port server-id)
		   conn
		   (let* ((curr-secs (current-seconds)))
		     ;; rm the (last server) would go here
		     (if (> (- curr-secs (tt-last-serv-start ttdat)) 30)
			 (begin
			   (tt-last-serv-start-set! ttdat curr-secs)
			   (server-start-proc))) ;; don't try and start server unless 30 sec has gone by since last attempt
		     (thread-sleep! 1)
		     (tt:client-connect-to-server ttdat dbfname run-id testsuite)))))
	    (else
	     (debug:print-info 0 *default-log-port* "No server found. Starting one for run-id "run-id" in dbfile "dbfname)
	     (tt-last-serv-start-set! ttdat (current-seconds))
	     (server-start-proc)
	     (thread-sleep! 1)
	     (tt:client-connect-to-server ttdat dbfname run-id testsuite)))))))
    
(define (tt:ping host port server-id)
  (let*  ((res (tt:send-receive-direct host port `(ping #f #f #f)))) ;; please send me your server-id
    ;;

		(debug:print 0 *default-log-port* "WARNING: server is loaded, will try again in a second.")
		(thread-sleep! 1)
		(tt:handler  ttdat cmd run-id params attemptnum area-dat areapath readonly-mode dbfname testsuite mtexe))
	       (else
		result)))
	    (else
	     (if (not res)
		 (begin ;; let* ((srvfile (tt-conn-servinf-file ))) ;; server likely died
		   (hash-table-set! (tt-conns ttdat) dbfname #f)
		   (debug:print 0 *default-log-port* "INFO: connection to server broken, reconnecting.")
		   (tt:handler ttdat cmd run-id params attemptnum area-dat areapath readonly-mode dbfname testsuite mtexe))
		 (assert #f "FATAL: tt:handler received bad data "res)))))
	(begin
	  (thread-sleep! 1) ;; give it a rest and try again
	  (tt:handler ttdat cmd run-id params attemptnum area-dat areapath readonly-mode dbfname testsuite mtexe)))))