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(set! *runremote* (make-remote))
(let* ((server-info (remote-server-info *runremote*)))
(if server-info
(begin
(remote-server-url-set! *runremote* (server:record->url server-info))
(remote-server-id-set! *runremote* (server:record->id server-info)))))
(set! runremote *runremote*))) ;; new runremote will come from this on next iteration
;; DOT SET_HOMEHOST; // leaving off - doesn't really add to the clarity
;; DOT MUTEXLOCK -> SET_HOMEHOST [label="no homehost?"];
;; DOT SET_HOMEHOST -> MUTEXLOCK;
;; ensure we have a homehost record
(if (or (not (pair? (remote-hh-dat runremote))) ;; not on homehost
(not (cdr (remote-hh-dat runremote)))) ;; not on homehost
(thread-sleep! 0.1) ;; since we shouldn't get here, delay a little
(let ((hh-data (server:choose-server areapath 'homehost)))
(remote-hh-dat-set! runremote (or hh-data (cons #f #f)))))
;;(print "BB> readonly-mode is "readonly-mode" dbfile is "dbfile)
(cond
#;((> (- (current-seconds)(remote-connect-time runremote)) 180) ;; reconnect to server every 180 seconds
(debug:print 0 *default-log-port* "Forcing reconnect to server(s) due to 180 second timeout.")
(set! *runremote* #f)
;; BUG: close-connections should go here?
(mutex-unlock! *rmt-mutex*)
(rmt:send-receive cmd rid params attemptnum: 1 area-dat: area-dat))
;;DOT EXIT;
;;DOT MUTEXLOCK -> EXIT [label="> 15 attempts"]; {rank=same "case 1" "EXIT" }
;; give up if more than 150 attempts
((> attemptnum 150)
(debug:print 0 *default-log-port* "ERROR: 150 tries to start/connect to server. Giving up.")
(exit 1))
;;DOT CASE2 [label="local\nreadonly\nquery"];
;;DOT MUTEXLOCK -> CASE2; {rank=same "case 2" CASE2}
;;DOT CASE2 -> "rmt:open-qry-close-locally";
;; 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)
)
;;DOT CASE3 [label="write in\nread-only mode"];
;;DOT MUTEXLOCK -> CASE3 [label="readonly\nmode?"]; {rank=same "case 3" CASE3}
;;DOT CASE3 -> "#f";
;; 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)
;;
;;DOT CASE4 [label="reset\nconnection"];
;;DOT MUTEXLOCK -> CASE4 [label="have connection,\nlast_access > expire_time"]; {rank=same "case 4" CASE4}
;;DOT CASE4 -> "rmt:send-receive";
;; reset the connection if it has been unused too long
((and runremote
(remote-api-url runremote)
(> (current-seconds) ;; if it has been more than server-timeout seconds since last contact, close this connection and start a new on
(+ (remote-last-access runremote)
(remote-server-timeout runremote))))
(debug:print-info 0 *default-log-port* "Connection to " (remote-server-url runremote) " expired due to no accesses in " (remote-server-timeout runremote) " seconds, forcing new connection.")
(http-transport:close-connections runremote)
;; moving this setting of runremote conndat to #f to inside the http-transport:close-connections
;; (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))
;;DOT CASE5 [label="local\nread"];
;;DOT MUTEXLOCK -> CASE5 [label="server not required,\non homehost,\nread-only query"]; {rank=same "case 5" CASE5};
;;DOT CASE5 -> "rmt:open-qry-close-locally";
;; on homehost and this is a read
((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
(rmt:on-homehost? runremote)
(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))
;;DOT CASE6 [label="init\nremote"];
;;DOT MUTEXLOCK -> CASE6 [label="on homehost,\nwrite query,\nhave server,\ncan't reach it"]; {rank=same "case 6" CASE6};
;;DOT CASE6 -> "rmt:send-receive";
;; on homehost and this is a write, we already have a server, but server has died
;; reinstate this keep-alive section but inject a time condition into the (add ...
;;
;; ((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) (remote-server-id runremote)))) ;; server has died. NOTE: this is not a cheap call! Need better approach.
;; (debug:print 0 *default-log-port* "WARNING: server appears to have died, trying to reconnect, case 6")
;; (http-transport:close-connections area-dat: runremote) ;; make sure to clean up
;; (set! *runremote* (make-remote))
;; (let* ((server-info (remote-server-info *runremote*)))
;; (if server-info
;; (begin
;; (remote-server-url-set! *runremote* (server:record->url server-info))
;; (remote-server-id-set! *runremote* (server:record->id server-info)))))
;; (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))
;;DOT CASE7 [label="homehost\nwrite"];
;;DOT MUTEXLOCK -> CASE7 [label="server not required,\non homehost,\na write,\nhave a server"]; {rank=same "case 7" CASE7};
;;DOT CASE7 -> "rmt:open-qry-close-locally";
;; 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 (needed to sync written data back)
(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))
;;DOT CASE8 [label="force\nserver"];
;;DOT MUTEXLOCK -> CASE8 [label="server not required,\nhave homehost info,\nno connection yet,\nnot a read-only query"]; {rank=same "case 8" CASE8};
;;DOT CASE8 -> "rmt:open-qry-close-locally";
;; 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-info (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-info
(begin
(remote-server-url-set! runremote (server:record->url server-info)) ;; the string can be consumed by the client setup if needed
(remote-server-id-set! runremote (server:record->id server-info)))
(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)))
;;DOT CASE9 [label="force server\nnot on homehost"];
;;DOT MUTEXLOCK -> CASE9 [label="no connection\nand either require server\nor not on homehost"]; {rank=same "case 9" CASE9};
;;DOT CASE9 -> "start\nserver" -> "rmt:send-receive";
((or (and (remote-force-server runremote) ;; we are forcing a server and don't yet have a connection to one
(not (remote-api-url runremote)))
(and (not (cdr (remote-hh-dat runremote))) ;; not on a homehost
(not (remote-api-url runremote)))) ;; and no connection
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 9, hh-dat: " (remote-hh-dat runremote) " runremote: " (remote->alist runremote))
(mutex-unlock! *rmt-mutex*)
(if (not (server:check-if-running *toppath*)) ;; who knows, maybe one has started up?
(server:start-and-wait *toppath*))
;; was: (remote-conndat-set! runremote (rmt:get-connection-info *toppath* runremote)) ;; calls client:setup which calls client:setup-http
(set! runremote (rmt:get-connection-info *toppath* runremote)) ;; calls client:setup which calls client:setup-http
(rmt:send-receive cmd rid params attemptnum: attemptnum)) ;; TODO: add back-off timeout as
;;DOT CASE10 [label="on homehost"];
;;DOT MUTEXLOCK -> CASE10 [label="server not required,\non homehost"]; {rank=same "case 10" CASE10};
;;DOT CASE10 -> "rmt:open-qry-close-locally";
;; 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))
;;DOT CASE11 [label="send_receive"];
;;DOT MUTEXLOCK -> CASE11 [label="else"]; {rank=same "case 11" CASE11};
;;DOT CASE11 -> "rmt:send-receive" [label="call failed"];
;;DOT CASE11 -> "RESULT" [label="call succeeded"];
;; not on homehost, do server query
(else (extras-case-11 *default-log-port* runremote cmd params attemptnum rid)))))
;;DOT }
;; 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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|
(set! *runremote* (make-remote))
(let* ((server-info (remote-server-info *runremote*)))
(if server-info
(begin
(remote-server-url-set! *runremote* (server:record->url server-info))
(remote-server-id-set! *runremote* (server:record->id server-info)))))
(set! runremote *runremote*))) ;; new runremote will come from this on next iteration
(http-transport-handler runremote cmd rid params attemptnum area-dat areapath readonly-mode)))
(define (http-transport-handler runremote cmd rid params attemptnum area-dat areapath readonly-mode)
;; DOT SET_HOMEHOST; // leaving off - doesn't really add to the clarity
;; DOT MUTEXLOCK -> SET_HOMEHOST [label="no homehost?"];
;; DOT SET_HOMEHOST -> MUTEXLOCK;
;; ensure we have a homehost record
(if (or (not (pair? (remote-hh-dat runremote))) ;; not on homehost
(not (cdr (remote-hh-dat runremote)))) ;; not on homehost
(thread-sleep! 0.1) ;; since we shouldn't get here, delay a little
(let ((hh-data (server:choose-server areapath 'homehost)))
(remote-hh-dat-set! runremote (or hh-data (cons #f #f)))))
;;(print "BB> readonly-mode is "readonly-mode" dbfile is "dbfile)
(cond
#;((> (- (current-seconds)(remote-connect-time runremote)) 180) ;; reconnect to server every 180 seconds
(debug:print 0 *default-log-port* "Forcing reconnect to server(s) due to 180 second timeout.")
(set! *runremote* #f)
;; BUG: close-connections should go here?
(mutex-unlock! *rmt-mutex*)
(rmt:send-receive cmd rid params attemptnum: 1 area-dat: area-dat))
;;DOT EXIT;
;;DOT MUTEXLOCK -> EXIT [label="> 15 attempts"]; {rank=same "case 1" "EXIT" }
;; give up if more than 150 attempts
((> attemptnum 150)
(debug:print 0 *default-log-port* "ERROR: 150 tries to start/connect to server. Giving up.")
(exit 1))
;;DOT CASE2 [label="local\nreadonly\nquery"];
;;DOT MUTEXLOCK -> CASE2; {rank=same "case 2" CASE2}
;;DOT CASE2 -> "rmt:open-qry-close-locally";
;; 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)
)
;;DOT CASE3 [label="write in\nread-only mode"];
;;DOT MUTEXLOCK -> CASE3 [label="readonly\nmode?"]; {rank=same "case 3" CASE3}
;;DOT CASE3 -> "#f";
;; 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)
;;
;;DOT CASE4 [label="reset\nconnection"];
;;DOT MUTEXLOCK -> CASE4 [label="have connection,\nlast_access > expire_time"]; {rank=same "case 4" CASE4}
;;DOT CASE4 -> "rmt:send-receive";
;; reset the connection if it has been unused too long
((and runremote
(remote-api-url runremote)
(> (current-seconds) ;; if it has been more than server-timeout seconds since last contact, close this connection and start a new on
(+ (remote-last-access runremote)
(remote-server-timeout runremote))))
(debug:print-info 0 *default-log-port* "Connection to " (remote-server-url runremote) " expired due to no accesses in " (remote-server-timeout runremote) " seconds, forcing new connection.")
(http-transport:close-connections runremote)
;; moving this setting of runremote conndat to #f to inside the http-transport:close-connections
;; (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))
;;DOT CASE5 [label="local\nread"];
;;DOT MUTEXLOCK -> CASE5 [label="server not required,\non homehost,\nread-only query"]; {rank=same "case 5" CASE5};
;;DOT CASE5 -> "rmt:open-qry-close-locally";
;; on homehost and this is a read
((and (not (remote-force-server runremote)) ;; honor forced use of server, i.e. server NOT required
(rmt:on-homehost? runremote)
(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))
;;DOT CASE6 [label="init\nremote"];
;;DOT MUTEXLOCK -> CASE6 [label="on homehost,\nwrite query,\nhave server,\ncan't reach it"]; {rank=same "case 6" CASE6};
;;DOT CASE6 -> "rmt:send-receive";
;; on homehost and this is a write, we already have a server, but server has died
;; reinstate this keep-alive section but inject a time condition into the (add ...
;;
;; ((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) (remote-server-id runremote)))) ;; server has died. NOTE: this is not a cheap call! Need better approach.
;; (debug:print 0 *default-log-port* "WARNING: server appears to have died, trying to reconnect, case 6")
;; (http-transport:close-connections area-dat: runremote) ;; make sure to clean up
;; (set! *runremote* (make-remote))
;; (let* ((server-info (remote-server-info *runremote*)))
;; (if server-info
;; (begin
;; (remote-server-url-set! *runremote* (server:record->url server-info))
;; (remote-server-id-set! *runremote* (server:record->id server-info)))))
;; (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))
;;DOT CASE7 [label="homehost\nwrite"];
;;DOT MUTEXLOCK -> CASE7 [label="server not required,\non homehost,\na write,\nhave a server"]; {rank=same "case 7" CASE7};
;;DOT CASE7 -> "rmt:open-qry-close-locally";
;; 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 (needed to sync written data back)
(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))
;;DOT CASE8 [label="force\nserver"];
;;DOT MUTEXLOCK -> CASE8 [label="server not required,\nhave homehost info,\nno connection yet,\nnot a read-only query"]; {rank=same "case 8" CASE8};
;;DOT CASE8 -> "rmt:open-qry-close-locally";
;; 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-info (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-info
(begin
(remote-server-url-set! runremote (server:record->url server-info)) ;; the string can be consumed by the client setup if needed
(remote-server-id-set! runremote (server:record->id server-info)))
(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)))
;;DOT CASE9 [label="force server\nnot on homehost"];
;;DOT MUTEXLOCK -> CASE9 [label="no connection\nand either require server\nor not on homehost"]; {rank=same "case 9" CASE9};
;;DOT CASE9 -> "start\nserver" -> "rmt:send-receive";
((or (and (remote-force-server runremote) ;; we are forcing a server and don't yet have a connection to one
(not (remote-api-url runremote)))
(and (not (cdr (remote-hh-dat runremote))) ;; not on a homehost
(not (remote-api-url runremote)))) ;; and no connection
(debug:print-info 12 *default-log-port* "rmt:send-receive, case 9, hh-dat: " (remote-hh-dat runremote) " runremote: " (remote->alist runremote))
(mutex-unlock! *rmt-mutex*)
(if (not (server:check-if-running *toppath*)) ;; who knows, maybe one has started up?
(server:start-and-wait *toppath*))
;; was: (remote-conndat-set! runremote (rmt:get-connection-info *toppath* runremote)) ;; calls client:setup which calls client:setup-http
(set! runremote (rmt:get-connection-info *toppath* runremote)) ;; calls client:setup which calls client:setup-http
(rmt:send-receive cmd rid params attemptnum: attemptnum)) ;; TODO: add back-off timeout as
;;DOT CASE10 [label="on homehost"];
;;DOT MUTEXLOCK -> CASE10 [label="server not required,\non homehost"]; {rank=same "case 10" CASE10};
;;DOT CASE10 -> "rmt:open-qry-close-locally";
;; 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))
;;DOT CASE11 [label="send_receive"];
;;DOT MUTEXLOCK -> CASE11 [label="else"]; {rank=same "case 11" CASE11};
;;DOT CASE11 -> "rmt:send-receive" [label="call failed"];
;;DOT CASE11 -> "RESULT" [label="call succeeded"];
;; not on homehost, do server query
(else (extras-case-11 *default-log-port* runremote cmd params attemptnum rid))))
;;DOT }
;; 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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