racket/net-doc/net/scribblings/ftp.scrbl
2014-12-02 00:13:32 -05:00

176 lines
6.5 KiB
Racket

#lang scribble/doc
@(require "common.rkt" (for-label net/ftp net/ftp-unit net/ftp-sig))
@title[#:tag "ftp"]{FTP: Client}
@author["Micah Flatt"
(author+email "Chen Xiao" "chenxiao770117@gmail.com")]
@defmodule[net/ftp]{The @racketmodname[net/ftp] library provides
utilities for FTP client operations.}
@section[#:tag "ftp-procs"]{Functions}
@defproc[(ftp-connection? [v any/c]) boolean?]{
Returns @racket[#t] if @racket[v] represents an FTP connection as
returned by @racket[ftp-establish-connection], @racket[#f] otherwise.}
@defproc[(ftp-establish-connection [server string?]
[port-no (integer-in 0 65535)]
[user string?]
[passwd string?])
ftp-connection?]{
Establishes an FTP connection with the given server using the supplied
username and password. The @racket[port-np] argument usually should be
@racket[21].}
@defproc[(ftp-close-connection [ftp-conn ftp-connection?]) void?]{
Closes an FTP connection.}
@defproc[(ftp-cd [ftp-conn ftp-connection?] [new-dir string?]) void?]{
Changes the current directory on the FTP server to @racket[new-dir].
The @racket[new-dir] argument is not interpreted at all, but simply
passed on to the server; it must not contain a newline.}
@defproc[(ftp-directory-list [ftp-conn ftp-connection?]
[path (or/c false/c string?) #f])
(listof (list/c (one-of/c "-" "d" "l")
string?
string?))]{
Returns a list of files and directories in the current directory of the
server, assuming that the server provides directory information in the
quasi-standard Unix format. If a @racket[path] argument is given, use
it instead of the current directory.
Each file or directory is represented by a list of three or four
strings. The first string is either @racket["-"], @racket["d"], or
@racket["l"], depending on whether the items is a file, directory, or
link, respectively. The second item is the file's date; to convert this
value to seconds consistent with @racket[file-seconds], pass the date
string to @racket[ftp-make-file-seconds]. The third string is the name
of the file or directory. If the item is a file (the first string is
@racket["-"]), and if the line that the server replied with has a size
in the expected place, then a fourth string containing this size is
included.
Warning: the FTP protocol has no specification for the reply format, so
this information can be unreliable.}
@defproc[(ftp-make-file-seconds [ftp-date string?]) exact-integer?]{
Takes a date string produced by @racket[ftp-directory-list] and
converts it to seconds (which can be used with
@racket[seconds->date]).
Warning: the FTP protocol has no specification for the reply format, so
this information can be unreliable.}
@defproc[(ftp-download-file [ftp-conn ftp-connection?]
[local-dir path-string?]
[file string?]
[#:progress progress-proc
(or/c #f
(-> (-> (values exact-nonnegative-integer?
evt?))
any))
#f])
void?]{
Downloads @racket[file] from the server's current directory and puts
it in @racket[local-dir] using the same name. If the file already
exists in the local directory, it is replaced, but only after the
transfer succeeds (i.e., the file is first downloaded to a temporary
file in @racket[local-dir], then moved into place on success).
If @racket[progress-proc] is not @racket[#f], then it is called with a
function @racket[_get-count] that returns two values: the number of bytes
transferred so far, and an event that becomes ready when the
transferred-bye count changes. The @racket[_get-count] function can be
called in any thread and any number of times. The @racket[progress-proc] function should
return immediately, perhaps starting a thread that periodically polls
@racket[_get-count]. Do not poll too frequently, or else polling
will slow the transfer; the second argument from @racket[_get-count]
is intended to limit polling.
@racketblock[
(ftp-download-file
ftp-conn "." "testfile"
#:progress
(lambda (get-count)
(thread
(lambda ()
(let loop ()
(define-values (count changed-evt) (get-count))
(printf "~a bytes downloaded\n" count)
(sync changed-evt)
(loop))))))
]}
@defproc[(ftp-upload-file [ftp-conn ftp-connection?]
[file-path path-string?]
[#:progress progress-proc
(or/c #f
(-> (-> (values exact-nonnegative-integer?
evt?))
any))
#f])
void?]{
Upload @racket[file-path] to the server's current directory using the same name.
If the file already exists in the local directory, it is replaced.
The @racket[progress-proc] argument is used in the same way as in @racket[ftp-download-file],
but to report uploaded bytes instead of downloaded bytes.}
@defproc[(ftp-delete-file [ftp-conn ftp-connection?]
[file-path path-string?]) void?]{
Delete the remote file use the @racket[file-path] on the server.}
@defproc[(ftp-make-directory [ftp-conn ftp-connection?]
[dir-name string?]) void?]{
Make remote directory use the @racket[dir-name].}
@defproc[(ftp-delete-directory [ftp-conn ftp-connection?]
[dir-name string?]) void?]{
Delete remote directory use the @racket[dir-name].}
@defproc[(ftp-rename-file [ftp-conn ftp-connection?]
[origin string?]
[dest string?]) void?]{
Rename remote file name from @racket[origin] to @racket[dest].}
@; ----------------------------------------
@section{FTP Unit}
@margin-note{@racket[ftp@] and @racket[ftp^] are deprecated.
They exist for backward-compatibility and will likely be removed in
the future. New code should use the @racketmodname[net/ftp] module.}
@defmodule[net/ftp-unit]
@defthing[ftp@ unit?]{
Imports nothing, exports @racket[ftp^].}
@; ----------------------------------------
@section{FTP Signature}
@defmodule[net/ftp-sig]
@defsignature[ftp^ ()]{}
Includes everything exported by the @racketmodname[net/ftp] module.