Module asyncftpclient

This module implements an asynchronous FTP client. It allows you to connect to an FTP server and perform operations on it such as for example:

• The upload of new files.
• The removal of existing files.
• Download of files.
• Changing of files' permissions.
• Navigation through the FTP server's directories.

Connecting to an FTP server

In order to begin any sort of transfer of files you must first connect to an FTP server. You can do so with the connect procedure.

import asyncdispatch, asyncftpclient
proc main() {.async.} =
  var ftp = newAsyncFtpClient("example.com", user = "test", pass = "test")
  await ftp.connect()
  echo("Connected")
waitFor(main())

A new main async procedure must be declared to allow the use of the await keyword. The connection will complete asynchronously and the client will be connected after the await ftp.connect() call.

Uploading a new file

After a connection is made you can use the store procedure to upload a new file to the FTP server. Make sure to check you are in the correct working directory before you do so with the pwd procedure, you can also instead specify an absolute path.

import asyncdispatch, asyncftpclient
proc main() {.async.} =
  var ftp = newAsyncFtpClient("example.com", user = "test", pass = "test")
  await ftp.connect()
  let currentDir = await ftp.pwd()
  assert currentDir == "/home/user/"
  await ftp.store("file.txt", "file.txt")
  echo("File finished uploading")
waitFor(main())

Checking the progress of a file transfer

The progress of either a file upload or a file download can be checked by specifying a onProgressChanged procedure to the store or retrFile procedures.

import asyncdispatch, asyncftpclient

proc onProgressChanged(total, progress: BiggestInt,
                        speed: float): Future[void] =
  echo("Uploaded ", progress, " of ", total, " bytes")
  echo("Current speed: ", speed, " kb/s")

proc main() {.async.} =
  var ftp = newAsyncFtpClient("example.com", user = "test", pass = "test")
  await ftp.connect()
  await ftp.store("file.txt", "/home/user/file.txt", onProgressChanged)
  echo("File finished uploading")
waitFor(main())

Imports

asyncdispatch, asyncnet, strutils, parseutils, os, times, ftpclient, net

Types

AsyncFtpClientObj = FtpBaseObj[AsyncSocket]

AsyncFtpClient = ref AsyncFtpClientObj

ProgressChangedProc = proc (total, progress: BiggestInt; speed: float): Future[void] {...}{.
    closure, gcsafe.}

Procs

proc send(ftp: AsyncFtpClient; m: string): Future[TaintedString] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Send a message to the server, and wait for a primary reply. \c\L is added for you.

Note: The server may return multiple lines of coded replies.

proc connect(ftp: AsyncFtpClient): Future[void] {...}{.raises: [FutureError],
    tags: [RootEffect].}

Connect to the FTP server specified by ftp.

proc pwd(ftp: AsyncFtpClient): Future[TaintedString] {...}{.raises: [FutureError],
    tags: [RootEffect].}

Returns the current working directory.

proc cd(ftp: AsyncFtpClient; dir: string): Future[void] {...}{.raises: [FutureError],
    tags: [RootEffect].}

Changes the current directory on the remote FTP server to dir.

proc cdup(ftp: AsyncFtpClient): Future[void] {...}{.raises: [FutureError],
    tags: [RootEffect].}

Changes the current directory to the parent of the current directory.

proc listDirs(ftp: AsyncFtpClient; dir = ""): Future[seq[string]] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Returns a list of filenames in the given directory. If dir is "", the current directory is used. If async is true, this function will return immediately and it will be your job to use asyncio's poll to progress this operation.

proc existsFile(ftp: AsyncFtpClient; file: string): Future[bool] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Determines whether file exists.

proc createDir(ftp: AsyncFtpClient; dir: string; recursive = false): Future[void] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Creates a directory dir. If recursive is true, the topmost subdirectory of dir will be created first, following the secondmost... etc. this allows you to give a full path as the dir without worrying about subdirectories not existing.

proc chmod(ftp: AsyncFtpClient; path: string; permissions: set[FilePermission]): Future[
    void] {...}{.raises: [FutureError], tags: [RootEffect].}

Changes permission of path to permissions.

proc list(ftp: AsyncFtpClient; dir = ""): Future[string] {...}{.raises: [FutureError],
    tags: [RootEffect].}

Lists all files in dir. If dir is "", uses the current working directory.

proc retrText(ftp: AsyncFtpClient; file: string): Future[string] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Retrieves file. File must be ASCII text.

proc defaultOnProgressChanged(total, progress: BiggestInt; speed: float): Future[void] {...}{.
    nimcall, gcsafe, procvar, raises: [FutureError, Exception], tags: [RootEffect].}

Default FTP onProgressChanged handler. Does nothing.

proc retrFile(ftp: AsyncFtpClient; file, dest: string;
             onProgressChanged: ProgressChangedProc = defaultOnProgressChanged): Future[
    void] {...}{.raises: [FutureError], tags: [RootEffect, TimeEffect, WriteIOEffect].}

Downloads file and saves it to dest. The EvRetr event is passed to the specified handleEvent function when the download is finished. The event's filename field will be equal to file.

proc store(ftp: AsyncFtpClient; file, dest: string;
          onProgressChanged: ProgressChangedProc = defaultOnProgressChanged): Future[
    void] {...}{.raises: [FutureError], tags: [RootEffect, ReadIOEffect, TimeEffect].}

Uploads file to dest on the remote FTP server. Usage of this function asynchronously is recommended to view the progress of the download. The EvStore event is passed to the specified handleEvent function when the upload is finished, and the filename field will be equal to file.

proc rename(ftp: AsyncFtpClient; nameFrom: string; nameTo: string): Future[void] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Rename a file or directory on the remote FTP Server from current name name_from to new name name_to

proc removeFile(ftp: AsyncFtpClient; filename: string): Future[void] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Delete a file filename on the remote FTP server

proc removeDir(ftp: AsyncFtpClient; dir: string): Future[void] {...}{.
    raises: [FutureError], tags: [RootEffect].}

Delete a directory dir on the remote FTP server

proc newAsyncFtpClient(address: string; port = Port(21); user, pass = ""): AsyncFtpClient {...}{.
    raises: [OSError, Exception], tags: [RootEffect].}

Creates a new AsyncFtpClient object.