This class implements the File Transfer Protocol. If you have used a command-line FTP program, and are familiar with the commands, you will be able to use this class easily. Some extra features are included to take advantage of Ruby's style and strengths.

Example

require 'net/ftp'

Example 1

ftp = Net::FTP.new('ftp.netlab.co.jp')
ftp.login
files = ftp.chdir('pub/lang/ruby/contrib')
files = ftp.list('n*')
ftp.getbinaryfile('nif.rb-0.91.gz', 'nif.gz', 1024)
ftp.close

Example 2

Net::FTP.open('ftp.netlab.co.jp') do |ftp|
  ftp.login
  files = ftp.chdir('pub/lang/ruby/contrib')
  files = ftp.list('n*')
  ftp.getbinaryfile('nif.rb-0.91.gz', 'nif.gz', 1024)
end

Major Methods

The following are the methods most likely to be useful to users:

Namespace
Methods
A
B
C
D
G
H
L
M
N
O
P
Q
R
S
V
Included Modules
Constants
MDTM_REGEXP = /^(\d\d\d\d)(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)/
 
Attributes
[R] binary

When true, transfers are performed in binary mode. Default: true.

[RW] debug_mode

When true, all traffic to and from the server is written to +$stdout+. Default: false.

[R] last_response

The server's last response.

[R] last_response_code

The server's last response code.

[R] lastresp

The server's last response code.

[RW] passive

When true, the connection is in passive mode. Default: false.

[RW] resume

Sets or retrieves the resumestatus, which decides whether incomplete transfers are resumed or restarted. Default: false.

[R] welcome

The server's welcome message.

Class Public methods
new(host = nil, user = nil, passwd = nil, acct = nil)

Creates and returns a new FTPobject. If a host is given, a connection is made. Additionally, if the useris given, the given user name, password, and (optionally) account are used to log in. See login.

# File lib/net/ftp.rb, line 130
def initialize(host = nil, user = nil, passwd = nil, acct = nil)
  super()
  @binary = true
  @passive = false
  @debug_mode = false
  @resume = false
  @sock = NullSocket.new
  @logged_in = false
  if host
    connect(host)
    if user
      login(user, passwd, acct)
    end
  end
end
open(host, user = nil, passwd = nil, acct = nil)

A synonym for FTP.new, but with a mandatory host parameter.

If a block is given, it is passed the FTPobject, which will be closed when the block finishes, or when an exception is raised.

# File lib/net/ftp.rb, line 112
def FTP.open(host, user = nil, passwd = nil, acct = nil)
  if block_given?
    ftp = new(host, user, passwd, acct)
    begin
      yield ftp
    ensure
      ftp.close
    end
  else
    new(host, user, passwd, acct)
  end
end
Instance Public methods
abort()

Aborts the previous command (ABOR command).

# File lib/net/ftp.rb, line 837
def abort
  line = "ABOR" + CRLF
  print "put: ABOR\n" if @debug_mode
  @sock.send(line, Socket::MSG_OOB)
  resp = getmultiline
  unless ["426", "226", "225"].include?(resp[0, 3])
    raise FTPProtoError, resp
  end
  return resp
end
acct(account)

Sends the ACCT command.

This is a less common FTP command, to send account information if the destination host requires it.

# File lib/net/ftp.rb, line 689
def acct(account)
  cmd = "ACCT " + account
  voidcmd(cmd)
end
binary=(newmode)

A setter to toggle transfers in binary mode. newmodeis either trueor false

# File lib/net/ftp.rb, line 148
def binary=(newmode)
  if newmode != @binary
    @binary = newmode
    send_type_command if @logged_in
  end
end
chdir(dirname)

Changes the (remote) directory.

# File lib/net/ftp.rb, line 759
def chdir(dirname)
  if dirname == ".."
    begin
      voidcmd("CDUP")
      return
    rescue FTPPermError => e
      if e.message[0, 3] != "500"
        raise e
      end
    end
  end
  cmd = "CWD " + dirname
  voidcmd(cmd)
end
close()

Closes the connection. Further operations are impossible until you open a new connection with connect.

# File lib/net/ftp.rb, line 907
def close
  @sock.close if @sock and not @sock.closed?
end
closed?()

Returns trueiff the connection is closed.

# File lib/net/ftp.rb, line 914
def closed?
  @sock == nil or @sock.closed?
end
connect(host, port = FTP_PORT)

Establishes an FTP connection to host, optionally overriding the default port. If the environment variable SOCKS_SERVERis set, sets up the connection through a SOCKS proxy. Raises an exception (typically Errno::ECONNREFUSED) if the connection cannot be established.

# File lib/net/ftp.rb, line 217
def connect(host, port = FTP_PORT)
  if @debug_mode
    print "connect: ", host, ", ", port, "\n"
  end
  synchronize do
    @sock = open_socket(host, port)
    voidresp
  end
end
delete(filename)

Deletes a file on the server.

# File lib/net/ftp.rb, line 745
def delete(filename)
  resp = sendcmd("DELE " + filename)
  if resp[0, 3] == "250"
    return
  elsif resp[0] == 5
    raise FTPPermError, resp
  else
    raise FTPReplyError, resp
  end
end
dir(*args)
get(remotefile, localfile = File.basename(remotefile), blocksize = DEFAULT_BLOCKSIZE)

Retrieves remotefilein whatever mode the session is set (text or binary). See gettextfile and getbinaryfile.

# File lib/net/ftp.rb, line 618
def get(remotefile, localfile = File.basename(remotefile),
        blocksize = DEFAULT_BLOCKSIZE, &block) # :yield: data
  if @binary
    getbinaryfile(remotefile, localfile, blocksize, &block)
  else
    gettextfile(remotefile, localfile, &block)
  end
end
getbinaryfile(remotefile, localfile = File.basename(remotefile), blocksize = DEFAULT_BLOCKSIZE)

Retrieves remotefilein binary mode, storing the result in localfile. If localfileis nil, returns retrieved data. If a block is supplied, it is passed the retrieved data in blocksizechunks.

# File lib/net/ftp.rb, line 560
def getbinaryfile(remotefile, localfile = File.basename(remotefile),
                  blocksize = DEFAULT_BLOCKSIZE) # :yield: data
  result = nil
  if localfile
    if @resume
      rest_offset = File.size?(localfile)
      f = open(localfile, "a")
    else
      rest_offset = nil
      f = open(localfile, "w")
    end
  elsif !block_given?
    result = ""
  end
  begin
    f.binmode if localfile
    retrbinary("RETR " + remotefile.to_s, blocksize, rest_offset) do |data|
      f.write(data) if localfile
      yield(data) if block_given?
      result.concat(data) if result
    end
    return result
  ensure
    f.close if localfile
  end
end
getdir()
gettextfile(remotefile, localfile = File.basename(remotefile))

Retrieves remotefilein ASCII (text) mode, storing the result in localfile. If localfileis nil, returns retrieved data. If a block is supplied, it is passed the retrieved data one line at a time.

# File lib/net/ftp.rb, line 594
def gettextfile(remotefile, localfile = File.basename(remotefile)) # :yield: line
  result = nil
  if localfile
    f = open(localfile, "w")
  elsif !block_given?
    result = ""
  end
  begin
    retrlines("RETR " + remotefile) do |line, newline|
      l = newline ? line + "\n" : line
      f.print(l) if localfile
      yield(line, newline) if block_given?
      result.concat(l) if result
    end
    return result
  ensure
    f.close if localfile
  end
end
help(arg = nil)

Issues the HELP command.

# File lib/net/ftp.rb, line 871
def help(arg = nil)
  cmd = "HELP"
  if arg
    cmd = cmd + " " + arg
  end
  sendcmd(cmd)
end
list(*args)

Returns an array of file information in the directory (the output is like `ls -l`). If a block is given, it iterates through the listing.

Also aliased as: ls, dir
# File lib/net/ftp.rb, line 713
def list(*args, &block) # :yield: line
  cmd = "LIST"
  args.each do |arg|
    cmd = cmd + " " + arg.to_s
  end
  if block
    retrlines(cmd, &block)
  else
    lines = []
    retrlines(cmd) do |line|
      lines << line
    end
    return lines
  end
end
login(user = "anonymous", passwd = nil, acct = nil)

Logs in to the remote host. The session must have been previously connected. If useris the string “anonymous” and the passwordis nil, a password of user@hostis synthesized. If the acctparameter is not nil, an FTP ACCT command is sent following the successful login. Raises an exception on error (typically Net::FTPPermError).

# File lib/net/ftp.rb, line 423
def login(user = "anonymous", passwd = nil, acct = nil)
  if user == "anonymous" and passwd == nil
    passwd = "anonymous@"
  end

  resp = ""
  synchronize do
    resp = sendcmd('USER ' + user)
    if resp[0] == 3
      raise FTPReplyError, resp if passwd.nil?
      resp = sendcmd('PASS ' + passwd)
    end
    if resp[0] == 3
      raise FTPReplyError, resp if acct.nil?
      resp = sendcmd('ACCT ' + acct)
    end
  end
  if resp[0] != 2
    raise FTPReplyError, resp
  end
  @welcome = resp
  send_type_command
  @logged_in = true
end
ls(*args)
mdtm(filename)

Issues the MDTM command. TODO: more info.

# File lib/net/ftp.rb, line 861
def mdtm(filename)
  resp = sendcmd("MDTM " + filename)
  if resp[0, 3] == "213"
    return resp[3 .. -1].strip
  end
end
mkdir(dirname)

Creates a remote directory.

# File lib/net/ftp.rb, line 802
def mkdir(dirname)
  resp = sendcmd("MKD " + dirname)
  return parse257(resp)
end
mtime(filename, local = false)

Returns the last modification time of the (remote) file. If localis true, it is returned as a local time, otherwise it's a UTC time.

# File lib/net/ftp.rb, line 793
def mtime(filename, local = false)
  str = mdtm(filename)
  ary = str.scan(MDTM_REGEXP)[0].collect {|i| i.to_i}
  return local ? Time.local(*ary) : Time.gm(*ary)
end
nlst(dir = nil)

Returns an array of filenames in the remote directory.

# File lib/net/ftp.rb, line 697
def nlst(dir = nil)
  cmd = "NLST"
  if dir
    cmd = cmd + " " + dir
  end
  files = []
  retrlines(cmd) do |line|
    files.push(line)
  end
  return files
end
noop()

Issues a NOOP command.

Does nothing except return a response.

# File lib/net/ftp.rb, line 891
def noop
  voidcmd("NOOP")
end
put(localfile, remotefile = File.basename(localfile), blocksize = DEFAULT_BLOCKSIZE, &block)

Transfers localfileto the server in whatever mode the session is set (text or binary). See puttextfile and putbinaryfile.

# File lib/net/ftp.rb, line 674
def put(localfile, remotefile = File.basename(localfile),
        blocksize = DEFAULT_BLOCKSIZE, &block)
  if @binary
    putbinaryfile(localfile, remotefile, blocksize, &block)
  else
    puttextfile(localfile, remotefile, &block)
  end
end
putbinaryfile(localfile, remotefile = File.basename(localfile), blocksize = DEFAULT_BLOCKSIZE)

Transfers localfileto the server in binary mode, storing the result in remotefile. If a block is supplied, calls it, passing in the transmitted data in blocksizechunks.

# File lib/net/ftp.rb, line 632
def putbinaryfile(localfile, remotefile = File.basename(localfile),
                  blocksize = DEFAULT_BLOCKSIZE, &block) # :yield: data
  if @resume
    begin
      rest_offset = size(remotefile)
    rescue Net::FTPPermError
      rest_offset = nil
    end
  else
    rest_offset = nil
  end
  f = open(localfile)
  begin
    f.binmode
    if rest_offset
      storbinary("APPE " + remotefile, f, blocksize, rest_offset, &block)
    else
      storbinary("STOR " + remotefile, f, blocksize, rest_offset, &block)
    end
  ensure
    f.close
  end
end
puttextfile(localfile, remotefile = File.basename(localfile))

Transfers localfileto the server in ASCII (text) mode, storing the result in remotefile. If callback or an associated block is supplied, calls it, passing in the transmitted data one line at a time.

# File lib/net/ftp.rb, line 661
def puttextfile(localfile, remotefile = File.basename(localfile), &block) # :yield: line
  f = open(localfile)
  begin
    storlines("STOR " + remotefile, f, &block)
  ensure
    f.close
  end
end
pwd()

Returns the current remote directory.

Also aliased as: getdir
# File lib/net/ftp.rb, line 817
def pwd
  resp = sendcmd("PWD")
  return parse257(resp)
end
quit()

Exits the FTP session.

# File lib/net/ftp.rb, line 882
def quit
  voidcmd("QUIT")
end
rename(fromname, toname)

Renames a file on the server.

# File lib/net/ftp.rb, line 734
def rename(fromname, toname)
  resp = sendcmd("RNFR " + fromname)
  if resp[0] != 3
    raise FTPReplyError, resp
  end
  voidcmd("RNTO " + toname)
end
retrbinary(cmd, blocksize, rest_offset = nil)

Puts the connection into binary (image) mode, issues the given command, and fetches the data returned, passing it to the associated block in chunks of blocksizecharacters. Note that cmdis a server command (such as “RETR myfile”).

# File lib/net/ftp.rb, line 454
def retrbinary(cmd, blocksize, rest_offset = nil) # :yield: data
  synchronize do
    with_binary(true) do
      conn = transfercmd(cmd, rest_offset)
      loop do
        data = conn.read(blocksize)
        break if data == nil
        yield(data)
      end
      conn.close
      voidresp
    end
  end
end
retrlines(cmd)

Puts the connection into ASCII (text) mode, issues the given command, and passes the resulting data, one line at a time, to the associated block. If no block is given, prints the lines. Note that cmdis a server command (such as “RETR myfile”).

# File lib/net/ftp.rb, line 475
def retrlines(cmd) # :yield: line
  synchronize do
    with_binary(false) do
      conn = transfercmd(cmd)
      loop do
        line = conn.gets
        break if line == nil
        yield(line.sub(/\r?\n\z/, ""), !line.match(/\n\z/).nil?)
      end
      conn.close
      voidresp
    end
  end
end
rmdir(dirname)

Removes a remote directory.

# File lib/net/ftp.rb, line 810
def rmdir(dirname)
  voidcmd("RMD " + dirname)
end
sendcmd(cmd)

Sends a command and returns the response.

# File lib/net/ftp.rb, line 322
def sendcmd(cmd)
  synchronize do
    putline(cmd)
    return getresp
  end
end
set_socket(sock, get_greeting = true)

WRITEME or make private

# File lib/net/ftp.rb, line 230
def set_socket(sock, get_greeting = true)
  synchronize do
    @sock = sock
    if get_greeting
      voidresp
    end
  end
end
site(arg)

Issues a SITE command.

# File lib/net/ftp.rb, line 898
def site(arg)
  cmd = "SITE " + arg
  voidcmd(cmd)
end
size(filename)

Returns the size of the given (remote) filename.

# File lib/net/ftp.rb, line 777
def size(filename)
  with_binary(true) do
    resp = sendcmd("SIZE " + filename)
    if resp[0, 3] != "213"
      raise FTPReplyError, resp
    end
    return resp[3..-1].strip.to_i
  end
end
status()

Returns the status (STAT command).

# File lib/net/ftp.rb, line 851
def status
  line = "STAT" + CRLF
  print "put: STAT\n" if @debug_mode
  @sock.send(line, Socket::MSG_OOB)
  return getresp
end
storbinary(cmd, file, blocksize, rest_offset = nil)

Puts the connection into binary (image) mode, issues the given server-side command (such as “STOR myfile”), and sends the contents of the file named fileto the server. If the optional block is given, it also passes it the data, in chunks of blocksizecharacters.

# File lib/net/ftp.rb, line 496
def storbinary(cmd, file, blocksize, rest_offset = nil, &block) # :yield: data
  if rest_offset
    file.seek(rest_offset, IO::SEEK_SET)
  end
  synchronize do
    with_binary(true) do
      conn = transfercmd(cmd)
      loop do
        buf = file.read(blocksize)
        break if buf == nil
        conn.write(buf)
        yield(buf) if block
      end
      conn.close
      voidresp
    end
  end
rescue Errno::EPIPE
  # EPIPE, in this case, means that the data connection was unexpectedly
  # terminated.  Rather than just raising EPIPE to the caller, check the
  # response on the control connection.  If getresp doesn't raise a more
  # appropriate exception, re-raise the original exception.
  getresp
  raise
end
storlines(cmd, file)

Puts the connection into ASCII (text) mode, issues the given server-side command (such as “STOR myfile”), and sends the contents of the file named fileto the server, one line at a time. If the optional block is given, it also passes it the lines.

# File lib/net/ftp.rb, line 528
def storlines(cmd, file, &block) # :yield: line
  synchronize do
    with_binary(false) do
      conn = transfercmd(cmd)
      loop do
        buf = file.gets
        break if buf == nil
        if buf[-2, 2] != CRLF
          buf = buf.chomp + CRLF
        end
        conn.write(buf)
        yield(buf) if block
      end
      conn.close
      voidresp
    end
  end
rescue Errno::EPIPE
  # EPIPE, in this case, means that the data connection was unexpectedly
  # terminated.  Rather than just raising EPIPE to the caller, check the
  # response on the control connection.  If getresp doesn't raise a more
  # appropriate exception, re-raise the original exception.
  getresp
  raise
end
system()

Returns system information.

# File lib/net/ftp.rb, line 826
def system
  resp = sendcmd("SYST")
  if resp[0, 3] != "215"
    raise FTPReplyError, resp
  end
  return resp[4 .. -1]
end
voidcmd(cmd)

Sends a command and expect a response beginning with '2'.

# File lib/net/ftp.rb, line 332
def voidcmd(cmd)
  synchronize do
    putline(cmd)
    voidresp
  end
end