;;======================================================================
;; Copyright 2022, Matthew Welland.
;;
;; This file is part of Megatest.
;;
;; Megatest is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;;
;; Megatest is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with Megatest. If not, see <http://www.gnu.org/licenses/>.
;;======================================================================
(declare (unit dbmgrmod))
(declare (uses ulex))
(declare (uses apimod))
(declare (uses pkts))
(declare (uses commonmod))
(declare (uses dbmod))
(declare (uses mtargs))
(declare (uses portloggermod))
(declare (uses debugprint))
(module dbmgrmod
*
(import scheme
chicken.base
chicken.condition
chicken.file
chicken.format
chicken.port
chicken.process
chicken.process-context
chicken.process-context.posix
chicken.sort
chicken.string
chicken.time
(prefix sqlite3 sqlite3:)
matchable
md5
message-digest
regex
s11n
srfi-1
srfi-18
srfi-69
system-information
typed-records
pkts
ulex
commonmod
apimod
dbmod
debugprint
(prefix mtargs args:)
portloggermod
)
;; Configurations for server
;; (tcp-buffer-size 2048)
;; (max-connections 2048)
;; info about me as a listener and my connections to db servers
;; stored (for now) in *db-serv-info*
;;
(defstruct servdat
(host #f)
(port #f)
(uuid #f)
(dbfile #f)
(uconn #f) ;; this is the listener for this process
(mode #f)
(status 'starting)
(trynum 0) ;; count the number of ports we've tried
(conns (make-hash-table)) ;; apath/dbname => conndat
)
(define *db-serv-info* #f)
(define (servdat->url sdat)
(conc (servdat-host sdat)":"(servdat-port sdat)))
;; db servers contact info
;;
(defstruct conndat
(apath #f)
(dbname #f)
(fullname #f)
(hostport #f)
(ipaddr #f)
(port #f)
(srvpkt #f)
(srvkey #f)
(lastmsg 0)
(expires 0))
(define *srvpktspec*
`((server (host . h)
(port . p)
(servkey . k)
(pid . i)
(ipaddr . a)
(dbpath . d))))
;;======================================================================
;; S U P P O R T F U N C T I O N S
;;======================================================================
;; set up the api proc, seems like there should be a better place for this?
;;
;; IS THIS NEEDED ANYMORE? TODO - REMOVE IF POSSIBLE
;;
;; (define api-proc (make-parameter conc))
;; (api-proc api:execute-requests)
;; do we have a connection to apath dbname and
;; is it not expired? then return it
;;
;; else setup a connection
;;
;; if that fails, return '(#f "some reason") ;; NB// convert to raising an exception
;;
(define (rmt:get-conn remdat apath dbname)
(let* ((fullname (db:dbname->path apath dbname)))
(hash-table-ref/default (servdat-conns remdat) fullname #f)))
(define (rmt:drop-conn remdat apath dbname)
(let* ((fullname (db:dbname->path apath dbname)))
(hash-table-delete! (servdat-conns remdat) fullname)))
(define (rmt:find-main-server uconn apath dbname)
(let* ((pktsdir (get-pkts-dir apath))
(all-srvpkts (get-all-server-pkts pktsdir *srvpktspec*))
(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
;;
;; connections for other servers happens by requesting from main
;;
;; TODO: This is unnecessarily re-creating the record in the hash table
;;
(define (rmt:open-main-connection remdat apath)
(let* ((fullpath (db:dbname->path apath ".db/main.db"))
(conns (servdat-conns remdat))
(conn (rmt:get-conn remdat apath ".db/main.db")) ;; (hash-table-ref/default conns fullpath #f)) ;; TODO - create call for this
(myconn (servdat-uconn remdat)))
(cond
((not myconn)
(servdat-uconn-set! remdat (make-udat))
(rmt:open-main-connection remdat apath))
((and conn ;; conn is NOT a socket, just saying ...
(< (current-seconds) (conndat-expires conn)))
#t) ;; we are current and good to go - we'll deal elsewhere with a server that was killed or died
((and conn
(>= (current-seconds)(conndat-expires conn)))
(debug:print-info 0 *default-log-port* "connection to "fullpath" server expired. Reconnecting.")
(rmt:drop-conn remdat apath ".db/main.db") ;;
(rmt:open-main-connection remdat apath))
(else
;; Below we will find or create and connect to main
(debug:print-info 0 *default-log-port* "rmt:open-main-connection - starting from scratch")
(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))
(thread-sleep! 0.25))
(mutex-unlock! *connstart-mutex*)
(rmt:open-main-connection remdat apath) ;; TODO: Add limit to number of tries
)))
(if (not the-srv) ;; have server, try connecting to it
(start-main-srv)
(let* ((srv-addr (server-address the-srv)) ;; need serv
(ipaddr (alist-ref 'ipaddr the-srv))
(port (alist-ref 'port the-srv))
(srvkey (alist-ref 'servkey the-srv))
(fullpath (db:dbname->path apath dbname))
(new-the-srv (make-conndat
apath: apath
dbname: dbname
fullname: fullpath
hostport: srv-addr
;; socket: (open-nn-connection srv-addr) - TODO - open ulex connection?
ipaddr: ipaddr
port: port
srvpkt: the-srv
srvkey: srvkey ;; generated by rmt:get-signature on the server side
lastmsg: (current-seconds)
expires: (+ (current-seconds)
(server:expiration-timeout)
-2) ;; this needs to be gathered during the ping
)))
(hash-table-set! conns fullpath new-the-srv)))
#t)))))
;; NB// sinfo is a servdat struct
;;
(define (rmt:general-open-connection sinfo apath dbname #!key (num-tries 5))
(assert (not (equal? dbname ".db/main.db")) "ERROR: general-open-connection should never be called with main as the db")
(let* ((mdbname ".db/main.db") ;; (db:run-id->dbname #f)) TODO: put this back to the lookup when stable
(fullname (db:dbname->path apath dbname))
(conns (servdat-conns sinfo))
(mconn (rmt:get-conn sinfo apath ".db/main.db"))
(dconn (rmt:get-conn sinfo apath dbname)))
#;(if (and mconn
(not (debug:print-logger)))
(begin
(debug:print-info 0 *default-log-port* "Turning on logging to main, look in logs dir for main log.")
(debug:print-logger rmt:log-to-main)))
(cond
((and mconn
dconn
(< (current-seconds)(conndat-expires dconn)))
#t) ;; good to go
((not mconn) ;; no channel open to main? open it...
(rmt:open-main-connection sinfo apath)
(rmt:general-open-connection sinfo apath dbname num-tries: (- num-tries 1)))
((not dconn) ;; no channel open to dbname?
(let* ((res (rmt:send-receive sinfo apath mdbname 'get-server `(,apath ,dbname))))
(case res
((server-started)
(if (> num-tries 0)
(begin
(thread-sleep! 2)
(rmt:general-open-connection sinfo apath dbname num-tries: (- num-tries 1)))
(begin
(debug:print-error 0 *default-log-port* "Failed to start servers needed or open channel to "apath", "dbname)
(exit 1))))
(else
(if (list? res) ;; server has been registered and the info was returned. pass it on.
(begin ;; ("192.168.0.9" 53817
;; "5e34239f48e8973b3813221e54701a01" "24310"
;; "192.168.0.9"
;; "/home/matt/data/megatest/tests/simplerun"
;; ".db/1.db")
(match
res
((host port servkey pid ipaddr apath dbname)
(debug:print-info 0 *default-log-port* "got "res)
(hash-table-set! conns
fullname
(make-conndat
apath: apath
dbname: dbname
hostport: (conc host":"port)
;; socket: (open-nn-connection (conc host":"port)) ;; TODO - open ulex connection?
ipaddr: ipaddr
port: port
srvkey: servkey
lastmsg: (current-seconds)
expires: (+ (current-seconds)
(server:expiration-timeout)
-2))))
(else
(debug:print-info 0 *default-log-port* "return data from starting server did not match host port servkey pid ipaddr apath dbname " res)))
res)
(begin
(debug:print-info 0 *default-log-port* "Unexpected result: " res)
res)))))))
#t))
;;======================================================================
;; FOR DEBUGGING SET TO #t
;; (define *localmode* #t)
(define *localmode* #f)
(define *dbstruct* (make-dbr:dbstruct))
;; Defaults to current area
;;
(define (rmt:send-receive cmd rid params #!key (attemptnum 1)(area-dat #f))
(let* ((apath *toppath*)
(sinfo *db-serv-info*)
(dbname (db:run-id->dbname rid)))
(if (not *db-serv-info*)
(begin
(set! *db-serv-info* (make-servdat))
(set! sinfo *db-serv-info*)))
(rmt:open-main-connection sinfo apath)
(if rid (rmt:general-open-connection sinfo apath dbname))
;; (if (not (member cmd '(log-to-main)))
;; (debug:print-info 0 *default-log-port* "rmt:send-receive "cmd" params="params))
(let* ((cdat (rmt:get-conn sinfo apath dbname)))
(assert cdat "FATAL: rmt:send-receive-real called without the needed channels opened")
(let* ((uconn (servdat-uconn sinfo)) ;; get the interface to ulex
;; then send-receive using the ulex layer to host-port stored in cdat
(res (send-receive uconn (conndat-hostport cdat) cmd params)))
(conndat-expires-set! cdat (+ (current-seconds)
(server:expiration-timeout)
-2)) ;; two second margin for network time misalignments etc.
res))))
;; db is at apath/.db/dbname, rid is an intermediary solution and will be removed
;; sometime in the future.
;;
;; Purpose - call the main.db server and request a server be started
;; for the given area path and dbname
;;
(define (rmt:print-db-stats)
(let ((fmtstr "~40a~7-d~9-d~20,2-f")) ;; "~20,2-f"
(debug:print 18 *default-log-port* "DB Stats, "(seconds->year-week/day-time (current-seconds))"\n=====================")
(debug:print 18 *default-log-port* (format #f "~40a~8a~10a~10a" "Cmd" "Count" "TotTime" "Avg"))
(for-each (lambda (cmd)
(let ((cmd-dat (hash-table-ref *db-stats* cmd)))
(debug:print 18 *default-log-port* (format #f fmtstr cmd (vector-ref cmd-dat 0) (vector-ref cmd-dat 1) (/ (vector-ref cmd-dat 1)(vector-ref cmd-dat 0))))))
(sort (hash-table-keys *db-stats*)
(lambda (a b)
(> (vector-ref (hash-table-ref *db-stats* a) 0)
(vector-ref (hash-table-ref *db-stats* b) 0)))))))
(define (rmt:get-max-query-average run-id)
(mutex-lock! *db-stats-mutex*)
(let* ((runkey (conc "run-id=" run-id " "))
(cmds (filter (lambda (x)
(substring-index runkey x))
(hash-table-keys *db-stats*)))
(res (if (null? cmds)
(cons 'none 0)
(let loop ((cmd (car cmds))
(tal (cdr cmds))
(max-cmd (car cmds))
(res 0))
(let* ((cmd-dat (hash-table-ref *db-stats* cmd))
(tot (vector-ref cmd-dat 0))
(curravg (/ (vector-ref cmd-dat 1) (vector-ref cmd-dat 0))) ;; count is never zero by construction
(currmax (max res curravg))
(newmax-cmd (if (> curravg res) cmd max-cmd)))
(if (null? tal)
(if (> tot 10)
(cons newmax-cmd currmax)
(cons 'none 0))
(loop (car tal)(cdr tal) newmax-cmd currmax)))))))
(mutex-unlock! *db-stats-mutex*)
res))
;; host and port are used to ensure we are remove proper records
(define (rmt:server-shutdown host port)
(let ((dbfile (servdat-dbfile *db-serv-info*)))
(debug:print-info 0 *default-log-port* "dbfile is "dbfile)
(if dbfile
(let* ((am-server (args:get-arg "-server"))
(dbfile (args:get-arg "-db"))
(apath *toppath*)
#;(sinfo *remotedat*)) ;; foundation for future fix
(if *dbstruct-db*
(let* ((dbdat (db:get-dbdat *dbstruct-db* apath dbfile))
(db (dbr:dbdat-db dbdat))
(inmem (dbr:dbdat-db dbdat)) ;; WRONG
)
;; do a final sync here
(debug:print-info 0 *default-log-port* "Doing final sync for "apath" "dbfile" at "(current-seconds))
(db:sync-inmem->disk *dbstruct-db* apath dbfile force-sync: #t)
;; let's finalize here
(debug:print-info 0 *default-log-port* "Finalizing db and inmem")
(if (sqlite3:database? db)
(sqlite3:finalize! db)
(debug:print-info 0 *default-log-port* "in rmt:server-shutdown, db is not a database, not finalizing..."))
(if (sqlite3:database? inmem)
(sqlite3:finalize! inmem)
(debug:print-info 0 *default-log-port* "in rmt:server-shutdown, inmem is not a database, not finalizing..."))
(debug:print-info 0 *default-log-port* "Finalizing db and inmem complete"))
(debug:print-info 0 *default-log-port* "Db was never opened, no cleanup to do."))
(if (not am-server)
(debug:print-info 0 *default-log-port* "I am not a server, should NOT get here!")
(if (string-match ".*/main.db$" dbfile)
(let ((pkt-file (conc (get-pkts-dir *toppath*)
"/" (servdat-uuid *db-serv-info*)
".pkt")))
(debug:print-info 0 *default-log-port* "removing pkt "pkt-file)
(delete-file* pkt-file)
(debug:print-info 0 *default-log-port* "Releasing lock (if any) for "dbfile ", host "host", port "port)
(db:with-lock-db
(servdat-dbfile *db-serv-info*)
(lambda (dbh dbfile)
(db:release-lock dbh dbfile host port)))) ;; I'm not the server - should not have a lock to remove
(let* ((sdat *db-serv-info*) ;; we have a run-id server
(host (servdat-host sdat))
(port (servdat-port sdat))
(uuid (servdat-uuid sdat))
(res (rmt:deregister-server *db-serv-info* *toppath* host port uuid dbfile)))
(debug:print-info 0 *default-log-port* "deregistered-server, res="res)
(debug:print-info 0 *default-log-port* "deregistering server "host":"port" with uuid "uuid)
)))))))
(define (common:run-sync?)
;; (and (common:on-homehost?)
(args:get-arg "-server"))
(define *rmt:run-mutex* (make-mutex))
(define *rmt:run-flag* #f)
(define (listener-running?)
(and *db-serv-info*
(servdat-uconn *db-serv-info*)))
;; Main entry point to start a server. was start-server
(define (rmt:run hostn)
(mutex-lock! *rmt:run-mutex*)
(if *rmt:run-flag*
(begin
(debug:print-warn 0 *default-log-port* "rmt:run already running.")
(mutex-unlock! *rmt:run-mutex*))
(begin
(set! *rmt:run-flag* #t)
(mutex-unlock! *rmt:run-mutex*)
;; ;; Configurations for server
;; (tcp-buffer-size 2048)
;; (max-connections 2048)
(debug:print 2 *default-log-port* "PID: "(current-process-id)". Attempting to start the server ...")
(if (listener-running?)
(let* ((uconn (servdat-uconn *db-serv-info*)))
(wait-and-close uconn))
(let* ((port (portlogger:open-run-close portlogger:find-port))
(handler-proc (lambda (rem-host-port qrykey cmd params) ;;
(set! *db-last-access* (current-seconds))
(assert (list? params) "FATAL: handler called with non-list params")
(assert (args:get-arg "-server") "FATAL: handler called on non-server side. cmd="cmd", params="params)
(debug:print 0 *default-log-port* "handler call: "cmd", params="params)
(api:execute-requests *dbstruct-db* cmd params))))
;; (api:process-request *dbstuct-db*
(if (not *db-serv-info*)
(set! *db-serv-info* (make-servdat host: hostn port: port)))
(let* ((uconn (run-listener handler-proc port))
(rport (udat-port uconn))) ;; the real port
(servdat-host-set! *db-serv-info* hostn)
(servdat-port-set! *db-serv-info* rport)
(servdat-uconn-set! *db-serv-info* uconn)
(wait-and-close uconn)
(db:print-current-query-stats)
)))
(let* ((host (servdat-host *db-serv-info*))
(port (servdat-port *db-serv-info*))
(mode (or (servdat-mode *db-serv-info*)
"non-db")))
;; server exit stuff here
;; (rmt:server-shutdown host port) - always do in on-exit
;; (portlogger:open-run-close portlogger:set-port port "released") ;; moved to on-exit
(debug:print-info 0 *default-log-port* "Server "host":"port" mode "mode"shutdown complete. Exiting")
))))
;;======================================================================
;; S E R V E R U T I L I T I E S
;;======================================================================
;;======================================================================
;; NEW SERVER METHOD
;;======================================================================
;; only use for main.db - need to re-write some of this :(
;;
(define (get-lock-db sdat dbfile host port)
(assert host "FATAL: get-lock-db called with host not set.")
(assert port "FATAL: get-lock-db called with port not set.")
(let* ((dbh (db:open-run-db dbfile db:initialize-db)) ;; open-run-db creates a standard db with schema used by all situations
(res (db:get-iam-server-lock dbh dbfile host port))
(uconn (servdat-uconn sdat)))
;; res => list then already locked, check server is responsive
;; => #t then sucessfully got the lock
;; => #f reserved for future use as to indicate something went wrong
(match res
((owner_pid owner_host owner_port event_time)
(if (server-ready? uconn (conc owner_host":"owner_port) "abc")
#f ;; locked by someone else
(begin ;; locked by someone dead and gone
(debug:print 0 *default-log-port* "WARNING: stale lock - have to steal it. This may fail.")
(db:steal-lock-db dbh dbfile port))))
(#t #t) ;; placeholder so that we don't touch res if it is #t
(else (set! res #f)))
(sqlite3:finalize! dbh)
res))
(define (register-server pkts-dir pkt-spec host port servkey ipaddr dbpath)
(let* ((pkt-dat `((host . ,host)
(port . ,port)
(servkey . ,servkey)
(pid . ,(current-process-id))
(ipaddr . ,ipaddr)
(dbpath . ,dbpath)))
(uuid (write-alist->pkt
pkts-dir
pkt-dat
pktspec: pkt-spec
ptype: 'server)))
(debug:print 0 *default-log-port* "Server on "host":"port" registered in pkt "uuid)
uuid))
(define (get-pkts-dir #!optional (apath #f))
(let* ((effective-toppath (or *toppath* apath)))
(assert effective-toppath
"ERROR: get-pkts-dir called without *toppath* set. Exiting.")
(let* ((pdir (conc effective-toppath "/.meta/srvpkts")))
(if (file-exists? pdir)
pdir
(begin
(handle-exceptions ;; this exception handler should NOT be needed but ...
exn
pdir
(create-directory pdir #t))
pdir)))))
;; given a pkts dir read
;;
(define (get-all-server-pkts pktsdir-in pktspec)
(let* ((pktsdir (if (file-exists? pktsdir-in)
pktsdir-in
(begin
(create-directory pktsdir-in #t)
pktsdir-in)))
(all-pkt-files (glob (conc pktsdir "/*.pkt"))))
(map (lambda (pkt-file)
(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* ((params `((cmd . ping)(key . ,key)))
(data `((cmd . ping)
(key . ,key)
(params . ,params))) ;; I don't get it.
(res (send-receive uconn host-port 'ping data)))
(if (eq? res 'ping-ack) ;; yep, likely it is who we want on the other end
res
#f)))
;; (begin (debug:print-info 0 *default-log-port* "server-ready? => "res) #f))))
; 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))
(host-port (conc host":"port))
(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))
(host-port (conc host":"port))
(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)
(if (null? serv-pkts)
#f
(let loop ((tail serv-pkts)
(best (car serv-pkts)))
(if (null? tail)
best
(let* ((candidate (car tail))
(candidate-bd (string->number (alist-ref 'D candidate)))
(best-bd (string->number (alist-ref 'D best)))
;; bigger number is younger
(candidate-z (alist-ref 'Z candidate))
(best-z (alist-ref 'Z best))
(new-best (cond
((> best-bd candidate-bd) ;; best is younger than candidate
candidate)
((< best-bd candidate-bd) ;; candidate is younger than best
best)
(else
(if (string>=? best-z candidate-z)
best
candidate))))) ;; use Z card as tie breaker
(if (null? tail)
new-best
(loop (cdr tail) new-best)))))))
;;======================================================================
;; END NEW SERVER METHOD
;;======================================================================
;; sdat must be defined and the host and port set and the same as previous
;;
(define (host-port-is-stable? sdat old-host old-port)
(and sdat
(let ((new-host (servdat-host sdat))
(new-port (servdat-port sdat)))
(and new-host
new-port
(equal? new-host old-host)
(equal? new-port old-port)))))
;; if .db/main.db check the pkts
;;
(define (rmt:wait-for-server pkts-dir db-file server-key)
(let* ((sdat *db-serv-info*))
(let loop ((start-time (current-milliseconds))
(changed #t)
(last-sdat "not this")
(last-host #f)
(last-port #f))
(begin ;; let ((sdat #f))
(thread-sleep! 0.01)
(debug:print-info 0 *default-log-port* "Waiting for server alive signature")
(mutex-lock! *heartbeat-mutex*)
(set! sdat *db-serv-info*)
(mutex-unlock! *heartbeat-mutex*)
(if (and sdat
(not changed)
(>= (- (current-milliseconds) start-time) 100))
(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 *db-serv-info*)
".pkt")))
(debug:print-info 0 *default-log-port* "Attempting to remove bogus pkt file "pktfile)
(delete-file* pktfile))))) ;; remove immediately instead of waiting for on-exit
(debug:print 0 *default-log-port* "best-srv-key: "best-srv-key", server-key: "server-key", i-am-srv: "i-am-srv)
;; am I the best-srv, compare server-keys to know
(if i-am-srv
(if (get-lock-db sdat db-file (servdat-host sdat)(servdat-port sdat)) ;; (db:get-iam-server-lock *dbstruct-db* *toppath* run-id)
(begin
(debug:print-info 0 *default-log-port* "I'm the server!")
(servdat-dbfile-set! sdat db-file)
(servdat-status-set! sdat 'db-locked))
(begin
(debug:print-info 0 *default-log-port* "I'm not the server, exiting.")
(bdat-time-to-exit-set! *bdat* #t)
(delete-pkt)
(thread-sleep! 0.2)
(exit)))
(begin
(debug:print-info 0 *default-log-port*
"Keys do not match "best-srv-key", "server-key", exiting.")
(bdat-time-to-exit-set! *bdat* #t)
(delete-pkt)
(thread-sleep! 0.2)
(exit)))
sdat))
(begin ;; sdat not yet contains server info
(debug:print-info 0 *default-log-port* "Still waiting, last-sdat=" last-sdat)
(thread-sleep! 0.1)
(if (> (- (current-milliseconds) start-time) 120000) ;; been waiting for two minutes
(begin
(debug:print-error 0 *default-log-port* "transport appears to have died, exiting server")
(exit))
(loop start-time
(not (host-port-is-stable? sdat last-host last-port))
sdat
(servdat-host sdat)
(servdat-port sdat)))))))))
(define (rmt:register-server sinfo apath iface port server-key dbname)
(servdat-conns sinfo) ;; just checking types
(rmt:open-main-connection sinfo apath) ;; we need a channel to main.db
(rmt:send-receive sinfo apath ;; params: host port servkey pid ipaddr dbpath
(db:run-id->dbname #f)
'register-server `(,iface
,port
,server-key
,(current-process-id)
,iface
,apath
,dbname)))
(define (rmt:get-count-servers sinfo apath)
(servdat-conns sinfo) ;; just checking types
(rmt:open-main-connection sinfo apath) ;; we need a channel to main.db
(rmt:send-receive sinfo apath ;; params: host port servkey pid ipaddr dbpath
(db:run-id->dbname #f)
'get-count-servers `(,apath)))
(define (rmt:get-servers-info apath)
(rmt:send-receive 'get-servers-info #f `(,apath)))
(define (rmt:deregister-server db-serv-info apath iface port server-key dbname)
(rmt:open-main-connection db-serv-info apath) ;; we need a channel to main.db
(rmt:send-receive db-serv-info apath ;; params: host port servkey pid ipaddr dbpath
(db:run-id->dbname #f)
'deregister-server `(,iface
,port
,server-key
,(current-process-id)
,iface
,apath
,dbname)))
(define (rmt:wait-for-stable-interface #!optional (num-tries-allowed 100))
;; wait until *db-serv-info* stops changing
(let* ((stime (current-seconds)))
(let loop ((last-host #f)
(last-port #f)
(tries 0))
(let* ((curr-host (and *db-serv-info* (servdat-host *db-serv-info*)))
(curr-port (and *db-serv-info* (servdat-port *db-serv-info*))))
;; first we verify port and interface, update *db-serv-info* in need be.
(cond
((> tries num-tries-allowed)
(debug:print 0 *default-log-port* "rmt:keep-running, giving up after trying for several minutes.")
(exit 1))
((not *db-serv-info*)
(thread-sleep! 0.25)
(loop curr-host curr-port (+ tries 1)))
((or (not last-host)(not last-port))
(debug:print 0 *default-log-port* "rmt:keep-running, still no interface, tries="tries)
(thread-sleep! 0.25)
(loop curr-host curr-port (+ tries 1)))
((or (not (equal? last-host curr-host))
(not (equal? last-port curr-port)))
(debug:print-info 0 *default-log-port* "WARNING: interface changed, refreshing iface and port info")
(thread-sleep! 0.25)
(loop curr-host curr-port (+ tries 1)))
((< (- (current-seconds) stime) 1) ;; keep up the looping until at least 3 seconds have passed
(thread-sleep! 0.5)
(loop curr-host curr-port (+ tries 1)))
(else
(rmt:get-signature) ;; sets *my-signature* as side effect
(servdat-status-set! *db-serv-info* 'interface-stable)
(debug:print 0 *default-log-port*
"SERVER STARTED: " curr-host
":" curr-port
" AT " (current-seconds) " server signature: " *my-signature*
" with "(servdat-trynum *db-serv-info*)" port changes")
(flush-output *default-log-port*)
#t))))))
;; run rmt:keep-running in a parallel thread to monitor that the db is being
;; used and to shutdown after sometime if it is not.
;;
(define (rmt:keep-running dbname)
;; if none running or if > 20 seconds since
;; server last used then start shutdown
;; This thread waits for the server to come alive
(debug:print-info 0 *default-log-port* "Starting the sync-back, keep alive thread in server")
(let* ((sinfo *db-serv-info*)
(server-start-time (current-seconds))
(pkts-dir (get-pkts-dir))
(server-key (rmt:get-signature)) ;; This servers key
(is-main (equal? (args:get-arg "-db") ".db/main.db"))
(last-access 0)
(server-timeout (server:expiration-timeout))
(shutdown-server-sequence (lambda (host port)
(set! *unclean-shutdown* #f) ;; Should not be needed anymore
(debug:print-info 0 *default-log-port* "Starting to shutdown the server. pid="(current-process-id))
;; (rmt:server-shutdown host port) -- called in on-exit
;; (portlogger:open-run-close portlogger:set-port port "released") called in on-exit
(exit)))
(timed-out? (lambda ()
(<= (+ last-access server-timeout)
(current-seconds)))))
(servdat-dbfile-set! *db-serv-info* (args:get-arg "-db"))
;; main and run db servers have both got wait logic (could/should merge it)
(if is-main
(rmt:wait-for-server pkts-dir dbname server-key)
(rmt:wait-for-stable-interface))
;; this is our forever loop
(let* ((iface (servdat-host *db-serv-info*))
(port (servdat-port *db-serv-info*))
(uconn (servdat-uconn *db-serv-info*)))
(let loop ((count 0)
(bad-sync-count 0)
(start-time (current-milliseconds)))
(if (and (not is-main)
(common:low-noise-print 60 "servdat-status"))
(debug:print-info 0 *default-log-port* "servdat-status is " (servdat-status *db-serv-info*)))
(mutex-lock! *heartbeat-mutex*)
;; set up the database handle
(if (not *dbstruct-db*) ;; no db opened yet, open the db and register with main if appropriate
(let ((watchdog (bdat-watchdog *bdat*)))
(debug:print 0 *default-log-port* "SERVER: dbprep")
(db:setup dbname) ;; sets *dbstruct-db* as side effect
(servdat-status-set! *db-serv-info* 'db-opened)
;; IFF I'm not main, call into main and register self
(if (not is-main)
(let ((res (rmt:register-server sinfo
*toppath* iface port
server-key dbname)))
(if res ;; we are the server
(servdat-status-set! *db-serv-info* 'have-interface-and-db)
;; now check that the db locker is alive, clear it out if not
(let* ((serv-info (rmt:server-info *toppath* dbname)))
(match serv-info
((host port servkey pid ipaddr apath dbpath)
(if (not (server-ready? uconn (conc host":"port) servkey))
(begin
(debug:print-info 0 *default-log-port* "Server registered but not alive. Removing and trying again.")
(rmt:deregister-server sinfo apath host port servkey dbpath) ;; servkey pid ipaddr apath dbpath)
(loop (+ count 1) bad-sync-count start-time))))
(else
(debug:print 0 *default-log-port* "We are not the server for "dbname", exiting. Server info is: "serv-info)
(exit)))))))
(debug:print 0 *default-log-port*
"SERVER: running, db "dbname" opened, megatest version: "
(common:get-full-version))
))
(db:sync-inmem->disk *dbstruct-db* *toppath* dbname force-sync: #t)
(mutex-unlock! *heartbeat-mutex*)
;; when things go wrong we don't want to be doing the various
;; queries too often so we strive to run this stuff only every
;; four seconds or so.
(let* ((sync-time (- (current-milliseconds) start-time))
(rem-time (quotient (- 4000 sync-time) 1000)))
(if (and (<= rem-time 4)
(> rem-time 0))
(thread-sleep! rem-time)))
;; Transfer *db-last-access* to last-access to use in checking that we are still alive
(set! last-access *db-last-access*)
(if (< count 1) ;; 3x3 = 9 secs aprox
(loop (+ count 1) bad-sync-count (current-milliseconds)))
(if (common:low-noise-print 60 "dbstats")
(begin
(debug:print 0 *default-log-port* "Server stats:")
(db:print-current-query-stats)))
(let* ((hrs-since-start (/ (- (current-seconds) server-start-time) 3600)))
(cond
((not *server-run*)
(debug:print-info 0 *default-log-port* "*server-run* set to #f. Shutting down.")
(shutdown-server-sequence (get-host-name) port))
((timed-out?)
(debug:print-info 0 *default-log-port* "Server timed out. seconds since last db access: " (- (current-seconds) last-access))
(shutdown-server-sequence (get-host-name) port))
((and *server-run*
(or (not (timed-out?))
(if is-main ;; do not exit if there are other servers (keep main open until all others gone)
(> (rmt:get-count-servers sinfo *toppath*) 1)
#f)))
(if (common:low-noise-print 120 "server continuing")
(debug:print-info 0 *default-log-port* "Server continuing, seconds since last db access: " (- (current-seconds) last-access)))
(loop 0 bad-sync-count (current-milliseconds)))
(else
(set! *unclean-shutdown* #f)
(debug:print-info 0 *default-log-port* "Server timed out. seconds since last db access: " (- (current-seconds) last-access))
(shutdown-server-sequence (get-host-name) port)
#;(debug:print-info 0 *default-log-port* "Sending 'quit to server, received: "
(open-send-receive-nn (conc iface":"port) ;; do this here and not in server-shutdown
(sexpr->string 'quit))))))))))
(define (rmt:get-reasonable-hostname)
(let* ((inhost (or (args:get-arg "-server") "-")))
(if (equal? inhost "-")
(get-host-name)
inhost)))
;; Call this to start the actual server
;;
;; all routes though here end in exit ...
;;
;; This is the point at which servers are started
;;
(define (rmt:server-launch dbname)
(debug:print-info 0 *default-log-port* "Entered rmt:server-launch")
(let* ((th2 (make-thread (lambda ()
(debug:print-info 0 *default-log-port* "Server run thread started")
(rmt:run (rmt:get-reasonable-hostname)))
"Server run"))
(th3 (make-thread (lambda ()
(debug:print-info 0 *default-log-port* "Server monitor thread started")
(if (args:get-arg "-server")
(rmt:keep-running dbname)
#;(rmt:wait-for-stable-interface)))
"Keep running")))
(thread-start! th2)
(thread-sleep! 0.252) ;; give the server time to settle before starting the keep-running monitor.
(thread-start! th3)
(set! *didsomething* #t)
(thread-join! th2)
(thread-join! th3))
#f)
;;======================================================================
;; S E R V E R - D I R E C T C A L L S
;;======================================================================
(define (rmt:kill-server run-id)
(rmt:send-receive 'kill-server #f (list run-id)))
(define (rmt:start-server run-id)
(rmt:send-receive 'start-server #f (list run-id)))
(define (rmt:server-info apath dbname)
(rmt:send-receive 'get-server-info #f (list apath dbname)))
)