59 lines
1.7 KiB
Racket
59 lines
1.7 KiB
Racket
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#lang racket
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;; Both `server' and `accept-and-handle' change
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;; to use a custodian.
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;; To start server
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;; (define stop (serve 8080))
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;; use your web browser to connect localhost:8080 greeted with "hello world"
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;; (stop) to close the server
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(define (serve port-no)
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(define main-cust (make-custodian))
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(parameterize ([current-custodian main-cust])
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(define listener (tcp-listen port-no 5 #t))
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(define (loop)
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(accept-and-handle listener)
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(loop))
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(thread loop))
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(lambda ()
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(displayln "\nGoodbye, shutting down all services\n")
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(custodian-shutdown-all main-cust)))
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(define (accept-and-handle listener)
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(define cust (make-custodian))
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(parameterize ([current-custodian cust])
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(define-values (in out) (tcp-accept listener))
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(thread (lambda ()
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(handle in out) ;; this handles connection with that specific client
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(close-input-port in)
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(close-output-port out))))
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;; Watcher thread:
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(thread (lambda ()
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(sleep 120)
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(custodian-shutdown-all cust))))
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(define (handle in out)
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; (server-loop in out)
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(sleep 5) ;; wait 5 seconds to guarantee client has already send message
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(define echo (read-line in)) ;; bind message to echo
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(displayln (string-append echo "\n"))
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; echo back the message, appending echo
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; could regex match the input to extract the name
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(writeln "Admin: Hello there" out) ;; append "echo " to echo and send back
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(flush-output out)
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)
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(define input-prompt "Hermes: ")
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(define (server-loop in out)
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(define echo (read-line in))
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(displayln echo)
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(display ">>> ")
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(define input (read))
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(writeln (string-append "Admin: " input) out)
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(flush-output out)
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; (sleep 10)
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(server-loop in out))
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