racket/collects/handin-client/client.ss
Eli Barzilay 9eace8d11d Use write+flush in client.ss,
remove bogus second write from tool.ss.

svn: r891
2005-09-21 03:18:33 +00:00

90 lines
2.7 KiB
Scheme

(module client mzscheme
(require (lib "mzssl.ss" "openssl"))
(provide handin-connect
submit-assignment
submit-addition
submit-password-change)
(define-struct handin (r w))
(define (write+flush port . xs)
(for-each (lambda (x) (write x port) (newline port)) xs)
(flush-output port))
(define (handin-connect server port pem)
(let ([ctx (ssl-make-client-context)])
(ssl-set-verify! ctx #t)
(ssl-load-verify-root-certificates! ctx pem)
(let-values ([(r w) (ssl-connect server port ctx)])
;; Sanity check: server sends "handin", first:
(let ([s (read-bytes 6 r)])
(unless (equal? #"handin" s)
(error 'handin-connect "bad handshake from server: ~e" s)))
;; Tell server protocol = 'original:
(write+flush w 'original)
;; One more sanity check: server recognizes protocol:
(let ([s (read r)])
(unless (eq? s 'original)
(error 'handin-connect "bad protocol from server: ~e" s)))
;; Return connection and list of active assignments:
(values (make-handin r w)
(let ([v (read r)])
(unless (and (list? v)
(andmap string? v))
(error 'handin-connect "failed to get active-assignment list from server"))
v)))))
(define (submit-assignment h username passwd assignment content on-commit)
(let ([r (handin-r h)]
[w (handin-w h)])
(write+flush w username passwd assignment)
(let ([v (read r)])
(unless (eq? v 'ok)
(error 'handin-connect "login error: ~a" v)))
(write+flush w (bytes-length content))
(let ([v (read r)])
(unless (eq? v 'go)
(error 'handin-connect "upload error: ~a" v)))
(fprintf w "$")
(display content w)
(flush-output w)
(let ([v (read r)])
(unless (eq? v 'confirm)
(error 'handin-connect "submit error: ~a" v)))
(on-commit)
(write+flush w 'check)
(let ([result-msg
(let ([v (read r)])
(cond
[(eq? v 'done) #f]
[(and (pair? v) (eq? (car v) 'result))
(cadr v)]
[else
(error 'handin-connect "commit probably unsucccesful: ~e" v)]))])
(close-input-port r)
(close-output-port w)
result-msg)))
(define (submit-addition h username full-name id email passwd)
(let ([r (handin-r h)]
[w (handin-w h)])
(write+flush w username 'create full-name id email passwd)
(let ([v (read r)])
(unless (eq? v 'ok)
(error 'handin-connect "update error: ~a" v)))
(close-input-port r)
(close-output-port w)))
(define (submit-password-change h username old-passwd new-passwd)
(let ([r (handin-r h)]
[w (handin-w h)])
(write+flush w username old-passwd 'change new-passwd)
(let ([v (read r)])
(unless (eq? v 'ok)
(error 'handin-connect "update error: ~a" v)))
(close-input-port r)
(close-output-port w))))