racket/collects/help/private/get-help-url.ss

68 lines
2.2 KiB
Scheme

(module get-help-url mzscheme
#| Library responsible for turning a path on disk into a URL the help desk can use |#
(require (lib "file.ss")
"internal-hp.ss"
(lib "contract.ss")
(lib "etc.ss")
(lib "config.ss" "planet")
(lib "dirs.ss" "setup"))
; given a manual path, convert to absolute Web path
; manual path is an anchored path to a doc manual, never a servlet
(define get-help-url
(opt-lambda (manual-path [anchor #f])
(let ([segments (explode-path (normalize-path manual-path))])
(let loop ([candidates manual-path-candidates])
(cond
;; shouldn't happen, unless documentation is outside
;; the set of doc dirs:
[(null? candidates) "/cannot-find-docs.html"]
[else
(let ([candidate (car candidates)])
(cond
[(subpath/tail (car candidate) segments)
=>
(λ (l-o-path)
((cadr candidate) l-o-path anchor))]
[else
(loop (cdr candidates))]))])))))
(define manual-path-candidates '())
(define (maybe-add-candidate candidate host)
(with-handlers ([exn:fail? void])
(set! manual-path-candidates
(cons (list (explode-path (normalize-path candidate))
(λ (segments anchor)
(format "http://~a:~a~a~a"
host
internal-port
(apply string-append (map (λ (x) (format "/~a" (path->string x)))
segments))
(if anchor
(string-append "#" anchor)
""))))
manual-path-candidates))))
;; Add doc dirs later, so that they take precedence:
(maybe-add-candidate (PLANET-DIR) planet-host)
(for-each (λ (dir host) (maybe-add-candidate dir host))
(append collects-dirs doc-dirs)
(append collects-hosts doc-hosts))
(define (subpath/tail short long)
(let loop ([short short]
[long long])
(cond
[(null? short) long]
[(null? long) #f]
[(equal? (car short) (car long))
(loop (cdr short) (cdr long))]
[else #f])))
(provide/contract (get-help-url
(opt->
((or/c path? path-string?))
(string?)
string?))))