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(client:setup areapath)
#f))))
(define *send-receive-mutex* (make-mutex)) ;; should have separate mutex per run-id
(define (rmt:send-receive cmd rid params #!key (attemptnum 1)(area-dat #f)) ;; start attemptnum at 1 so the modulo below works as expected
(rmt:open-qry-close-locally cmd 0 params))
#;(define (rmt:send-receive cmd rid params #!key (attemptnum 1)(area-dat #f)) ;; start attemptnum at 1 so the modulo below works as expected
#;(common:telemetry-log (conc "rmt:"(->string cmd))
payload: `((rid . ,rid)
(params . ,params)))
;; do all the prep locked under the rmt-mutex
(mutex-lock! *rmt-mutex*)
;; 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
(runremote (or area-dat
*runremote*))
(readonly-mode (rmtmod:calc-ro-mode runremote *toppath*)))
;; ensure we have a record for our connection for given area
(if (not runremote) ;; can remove this one. should never get here.
(begin
(set! *runremote* (make-remote))
(set! runremote *runremote*))) ;; new runremote will come from this on next iteration
;; ensure we have a homehost record
(if (not (pair? (remote-hh-dat runremote))) ;; not on homehost
(thread-sleep! 0.1) ;; since we shouldn't get here, delay a little
(remote-hh-dat-set! runremote (common:get-homehost)))
;;(print "BB> readonly-mode is "readonly-mode" dbfile is "dbfile)
(cond
;; give up if more than 15 attempts
((> attemptnum 15)
(debug:print 0 *default-log-port* "ERROR: 15 tries to start/connect to server. Giving up.")
(exit 1))
;; readonly mode, read request- handle it - case 2
((and readonly-mode
(member cmd api:read-only-queries))
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 2")
(rmt:open-qry-close-locally cmd 0 params)
)
;; readonly mode, write request. Do nothing, return #f
(readonly-mode (extras-readonly-mode *rmt-mutex* *default-log-port* cmd params))
;; This block was for pre-emptively resetting the connection if there had been no communication for some time.
;; I don't think it adds any value. If the server is not there, just fail and start a new connection.
;; also, the expire-time calculation might not be correct. We want, time-since-last-server-access > (server:get-timeout)
;;
;; reset the connection if it has been unused too long
((and runremote
(remote-conndat runremote)
(> (current-seconds) ;; if it has been more than server-timeout seconds since last contact, close this connection and start a new on
(+ (http-transport:server-dat-get-last-access (remote-conndat runremote))
(remote-server-timeout runremote))))
(debug:print-info 0 *default-log-port* "Connection to " (remote-server-url runremote) " expired due to no accesses, forcing new connection.")
(http-transport:close-connections area-dat: runremote)
(remote-conndat-set! runremote #f) ;; invalidate the connection, thus forcing a new connection.
(mutex-unlock! *rmt-mutex*)
(rmt:send-receive cmd rid params attemptnum: attemptnum))
;; on homehost and this is a read
((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
(cdr (remote-hh-dat runremote)) ;; on homehost
(member cmd api:read-only-queries)) ;; this is a read
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 5")
(rmt:open-qry-close-locally cmd 0 params))
;; on homehost and this is a write, we already have a server, but server has died
((and (cdr (remote-hh-dat runremote)) ;; on homehost
(not (member cmd api:read-only-queries)) ;; this is a write
(remote-server-url runremote) ;; have a server
(not (server:ping (remote-server-url runremote)))) ;; server has died. NOTE: this is not a cheap call! Need better approach.
(set! *runremote* (make-remote))
(remote-force-server-set! runremote (common:force-server?))
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 6")
(rmt:send-receive cmd rid params attemptnum: attemptnum))
;; on homehost and this is a write, we already have a server
((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
(cdr (remote-hh-dat runremote)) ;; on homehost
(not (member cmd api:read-only-queries)) ;; this is a write
(remote-server-url runremote)) ;; have a server
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 4.1")
(rmt:open-qry-close-locally cmd 0 params))
;; on homehost, no server contact made and this is a write, passively start a server
((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
(cdr (remote-hh-dat runremote)) ;; have homehost
(not (remote-server-url runremote)) ;; no connection yet
(not (member cmd api:read-only-queries))) ;; not a read-only query
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 8")
(let ((server-url (server:check-if-running *toppath*))) ;; (server:read-dotserver->url *toppath*))) ;; (server:check-if-running *toppath*))) ;; Do NOT want to run server:check-if-running - very expensive to do for every write call
(if server-url
(remote-server-url-set! runremote server-url) ;; the string can be consumed by the client setup if needed
(if (common:force-server?)
(server:start-and-wait *toppath*)
(server:kind-run *toppath*))))
(remote-force-server-set! runremote (common:force-server?))
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 8.1")
(rmt:open-qry-close-locally cmd 0 params))
((or (and (remote-force-server runremote) ;; we are forcing a server and don't yet have a connection to one
(not (remote-conndat runremote)))
(and (not (cdr (remote-hh-dat runremote))) ;; not on a homehost
(not (remote-conndat runremote)))) ;; and no connection
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 9, hh-dat: " (remote-hh-dat runremote) " conndat: " (remote-conndat runremote))
(mutex-unlock! *rmt-mutex*)
(if (not (server:check-if-running *toppath*)) ;; who knows, maybe one has started up?
(server:start-and-wait *toppath*))
(remote-conndat-set! runremote (rmt:get-connection-info *toppath*)) ;; calls client:setup which calls client:setup-http
(rmt:send-receive cmd rid params attemptnum: attemptnum)) ;; TODO: add back-off timeout as
;; all set up if get this far, dispatch the query
((and (not (remote-force-server runremote))
(cdr (remote-hh-dat runremote))) ;; we are on homehost
(mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 10")
(rmt:open-qry-close-locally cmd (if rid rid 0) params))
;; not on homehost, do server query
(else (extras-case-11 *default-log-port* runremote cmd params attemptnum rid)))))
;; bunch of small functions factored out of send-receive to make debug easier
;;
(define (extras-case-11 *default-log-port* runremote cmd params attemptnum rid)
;; (mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 9")
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|
(client:setup areapath)
#f))))
(define *send-receive-mutex* (make-mutex)) ;; should have separate mutex per run-id
(define (rmt:send-receive cmd rid params #!key (attemptnum 1)(area-dat #f)) ;; start attemptnum at 1 so the modulo below works as expected
(rmt:open-qry-close-locally cmd 0 params))
;;
;; ;; #;(common:telemetry-log (conc "rmt:"(->string cmd))
;; ;; #;(define (rmt:send-receive cmd rid params #!key (attemptnum 1)(area-dat #f)) ;; start attemptnum at 1 so the modulo below works as expected
;; ;;
;; ;; #;(common:telemetry-log (conc "rmt:"(->string cmd))
;; ;; payload: `((rid . ,rid)
;; ;; (params . ,params)))
;; ;;
;; ;; do all the prep locked under the rmt-mutex
;; (mutex-lock! *rmt-mutex*)
;;
;; ;; 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
;; (runremote (or area-dat
;; *runremote*))
;; (readonly-mode (rmtmod:calc-ro-mode runremote *toppath*)))
;;
;; ;; ensure we have a record for our connection for given area
;; (if (not runremote) ;; can remove this one. should never get here.
;; (begin
;; (set! *runremote* (make-remote))
;; (set! runremote *runremote*))) ;; new runremote will come from this on next iteration
;;
;; ;; ensure we have a homehost record
;; (if (not (pair? (remote-hh-dat runremote))) ;; not on homehost
;; (thread-sleep! 0.1) ;; since we shouldn't get here, delay a little
;; (remote-hh-dat-set! runremote (common:get-homehost)))
;;
;; ;;(print "BB> readonly-mode is "readonly-mode" dbfile is "dbfile)
;; (cond
;; ;; give up if more than 15 attempts
;; ((> attemptnum 15)
;; (debug:print 0 *default-log-port* "ERROR: 15 tries to start/connect to server. Giving up.")
;; (exit 1))
;;
;; ;; readonly mode, read request- handle it - case 2
;; ((and readonly-mode
;; (member cmd api:read-only-queries))
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 2")
;; (rmt:open-qry-close-locally cmd 0 params)
;; )
;;
;; ;; readonly mode, write request. Do nothing, return #f
;; (readonly-mode (extras-readonly-mode *rmt-mutex* *default-log-port* cmd params))
;;
;; ;; This block was for pre-emptively resetting the connection if there had been no communication for some time.
;; ;; I don't think it adds any value. If the server is not there, just fail and start a new connection.
;; ;; also, the expire-time calculation might not be correct. We want, time-since-last-server-access > (server:get-timeout)
;; ;;
;; ;; reset the connection if it has been unused too long
;; ((and runremote
;; (remote-conndat runremote)
;; (> (current-seconds) ;; if it has been more than server-timeout seconds since last contact, close this connection and start a new on
;; (+ (http-transport:server-dat-get-last-access (remote-conndat runremote))
;; (remote-server-timeout runremote))))
;; (debug:print-info 0 *default-log-port* "Connection to " (remote-server-url runremote) " expired due to no accesses, forcing new connection.")
;; (http-transport:close-connections area-dat: runremote)
;; (remote-conndat-set! runremote #f) ;; invalidate the connection, thus forcing a new connection.
;; (mutex-unlock! *rmt-mutex*)
;; (rmt:send-receive cmd rid params attemptnum: attemptnum))
;;
;; ;; on homehost and this is a read
;; ((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
;; (cdr (remote-hh-dat runremote)) ;; on homehost
;; (member cmd api:read-only-queries)) ;; this is a read
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 5")
;; (rmt:open-qry-close-locally cmd 0 params))
;;
;; ;; on homehost and this is a write, we already have a server, but server has died
;; ((and (cdr (remote-hh-dat runremote)) ;; on homehost
;; (not (member cmd api:read-only-queries)) ;; this is a write
;; (remote-server-url runremote) ;; have a server
;; (not (server:ping (remote-server-url runremote)))) ;; server has died. NOTE: this is not a cheap call! Need better approach.
;; (set! *runremote* (make-remote))
;; (remote-force-server-set! runremote (common:force-server?))
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 6")
;; (rmt:send-receive cmd rid params attemptnum: attemptnum))
;;
;; ;; on homehost and this is a write, we already have a server
;; ((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
;; (cdr (remote-hh-dat runremote)) ;; on homehost
;; (not (member cmd api:read-only-queries)) ;; this is a write
;; (remote-server-url runremote)) ;; have a server
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 4.1")
;; (rmt:open-qry-close-locally cmd 0 params))
;;
;; ;; on homehost, no server contact made and this is a write, passively start a server
;; ((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
;; (cdr (remote-hh-dat runremote)) ;; have homehost
;; (not (remote-server-url runremote)) ;; no connection yet
;; (not (member cmd api:read-only-queries))) ;; not a read-only query
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 8")
;; (let ((server-url (server:check-if-running *toppath*))) ;; (server:read-dotserver->url *toppath*))) ;; (server:check-if-running *toppath*))) ;; Do NOT want to run server:check-if-running - very expensive to do for every write call
;; (if server-url
;; (remote-server-url-set! runremote server-url) ;; the string can be consumed by the client setup if needed
;; (if (common:force-server?)
;; (server:start-and-wait *toppath*)
;; (server:kind-run *toppath*))))
;; (remote-force-server-set! runremote (common:force-server?))
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 8.1")
;; (rmt:open-qry-close-locally cmd 0 params))
;;
;; ((or (and (remote-force-server runremote) ;; we are forcing a server and don't yet have a connection to one
;; (not (remote-conndat runremote)))
;; (and (not (cdr (remote-hh-dat runremote))) ;; not on a homehost
;; (not (remote-conndat runremote)))) ;; and no connection
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 9, hh-dat: " (remote-hh-dat runremote) " conndat: " (remote-conndat runremote))
;; (mutex-unlock! *rmt-mutex*)
;; (if (not (server:check-if-running *toppath*)) ;; who knows, maybe one has started up?
;; (server:start-and-wait *toppath*))
;; (remote-conndat-set! runremote (rmt:get-connection-info *toppath*)) ;; calls client:setup which calls client:setup-http
;; (rmt:send-receive cmd rid params attemptnum: attemptnum)) ;; TODO: add back-off timeout as
;;
;; ;; all set up if get this far, dispatch the query
;; ((and (not (remote-force-server runremote))
;; (cdr (remote-hh-dat runremote))) ;; we are on homehost
;; (mutex-unlock! *rmt-mutex*)
;; (debug:print-info 12 *default-log-port* "rmt:send-receive, case 10")
;; (rmt:open-qry-close-locally cmd (if rid rid 0) params))
;;
;; ;; not on homehost, do server query
;; (else (extras-case-11 *default-log-port* runremote cmd params attemptnum rid)))))
;; bunch of small functions factored out of send-receive to make debug easier
;;
(define (extras-case-11 *default-log-port* runremote cmd params attemptnum rid)
;; (mutex-unlock! *rmt-mutex*)
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 9")
|