Protocol
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.
require 'net/ftp'
ftp = Net::FTP.new('example.com') 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
Net::FTP.open('example.com') 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
The following are the methods most likely to be useful to users:
When true
, all traffic to and from the server is written to
+$stdout+. Default: false
.
Number of seconds to wait for the connection to open. Any number may be
used, including Floats for fractional seconds. If the FTP object cannot open a connection in this many
seconds, it raises a Net::OpenTimeout exception. The default value is
nil
.
Number of seconds to wait for one block to be read (via one read(2) call). Any number may be used, including Floats for fractional seconds. If the FTP object cannot read data in this many seconds, it raises a Timeout::Error exception. The default value is 60 seconds.
Sets or retrieves the resume
status, which decides whether
incomplete transfers are resumed or restarted. Default:
false
.
Number of seconds to wait for the TLS handshake. Any number may be used,
including Floats for fractional seconds. If the FTP
object cannot complete the TLS handshake in this many seconds, it raises a
Net::OpenTimeout exception. The default value is nil
. If
ssl_handshake_timeout
is nil
,
open_timeout
is used instead.
When true
, connections are in passive mode per default.
Default: true
.
# File net/ftp.rb, line 151 def self.default_passive @@default_passive end
When true
, connections are in passive mode per default.
Default: true
.
# File net/ftp.rb, line 145 def self.default_passive=(value) @@default_passive = value end
Creates and returns a new FTP
object. If a host
is given, a connection is made.
options
is an option hash, each key of which is a symbol.
The available options are:
Port number (default value is 21)
If options is true, then an attempt will be made to use SSL (now TLS) to connect to the server. For this to work OpenSSL [OSSL] and the Ruby OpenSSL [RSSL] extensions need to be installed. If options is a hash, it’s passed to OpenSSL::SSL::SSLContext#set_params as parameters.
If true, TLS is used for data connections. Default: true
when
options is true.
Username for login. If options is the string
“anonymous” and the options is nil
,
“anonymous@” is used as a password.
Password for login.
Account information for ACCT.
When true
, the connection is in passive mode. Default:
true
.
Number of seconds to wait for the connection to open. See #open_timeout for details.
Default: nil
.
Number of seconds to wait for one block to be read. See #read_timeout for details.
Default: 60
.
Number of seconds to wait for the TLS handshake. See #ssl_handshake_timeout
for details. Default: nil
.
When true
, all traffic to and from the server is written to
+$stdout+. Default: false
.
# File net/ftp.rb, line 211 def initialize(host = nil, user_or_options = {}, passwd = nil, acct = nil) super() begin options = user_or_options.to_hash rescue NoMethodError # for backward compatibility options = {} options[:username] = user_or_options options[:password] = passwd options[:account] = acct end @host = nil if options[:ssl] unless defined?(OpenSSL::SSL) raise "SSL extension not installed" end ssl_params = options[:ssl] == true ? {} : options[:ssl] @ssl_context = SSLContext.new @ssl_context.set_params(ssl_params) if defined?(VerifyCallbackProc) @ssl_context.verify_callback = VerifyCallbackProc end @ssl_context.session_cache_mode = OpenSSL::SSL::SSLContext::SESSION_CACHE_CLIENT | OpenSSL::SSL::SSLContext::SESSION_CACHE_NO_INTERNAL_STORE @ssl_context.session_new_cb = proc {|sock, sess| @ssl_session = sess } @ssl_session = nil if options[:private_data_connection].nil? @private_data_connection = true else @private_data_connection = options[:private_data_connection] end else @ssl_context = nil if options[:private_data_connection] raise ArgumentError, "private_data_connection can be set to true only when ssl is enabled" end @private_data_connection = false end @binary = true if options[:passive].nil? @passive = @@default_passive else @passive = options[:passive] end if options[:debug_mode].nil? @debug_mode = false else @debug_mode = options[:debug_mode] end @resume = false @bare_sock = @sock = NullSocket.new @logged_in = false @open_timeout = options[:open_timeout] @ssl_handshake_timeout = options[:ssl_handshake_timeout] @read_timeout = options[:read_timeout] || 60 if host connect(host, options[:port] || FTP_PORT) if options[:username] login(options[:username], options[:password], options[:account]) end end end
A synonym for FTP.new
, but with a mandatory host parameter.
If a block is given, it is passed the FTP
object, which will
be closed when the block finishes, or when an exception is raised.
# File net/ftp.rb, line 161 def FTP.open(host, *args) if block_given? ftp = new(host, *args) begin yield ftp ensure ftp.close end else new(host, *args) end end
Aborts the previous command (ABOR command).
# File net/ftp.rb, line 1230 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
Sends the ACCT command.
This is a less common FTP command, to send account information if the destination host requires it.
# File net/ftp.rb, line 883 def acct(account) cmd = "ACCT " + account voidcmd(cmd) end
A setter to toggle transfers in binary mode. newmode
is either
true
or false
# File net/ftp.rb, line 278 def binary=(newmode) if newmode != @binary @binary = newmode send_type_command if @logged_in end end
Changes the (remote) directory.
# File net/ftp.rb, line 1151 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
Closes the connection. Further operations are impossible until you open a new connection with connect.
# File net/ftp.rb, line 1344 def close if @sock and not @sock.closed? begin @sock.shutdown(Socket::SHUT_WR) rescue nil orig, self.read_timeout = self.read_timeout, 3 @sock.read rescue nil ensure @sock.close self.read_timeout = orig end end end
Returns true
iff the connection is closed.
# File net/ftp.rb, line 1360 def closed? @sock == nil or @sock.closed? end
Establishes an FTP connection to host, optionally
overriding the default port. If the environment variable
SOCKS_SERVER
is set, sets up the connection through a SOCKS
proxy. Raises an exception (typically Errno::ECONNREFUSED
) if
the connection cannot be established.
# File net/ftp.rb, line 366 def connect(host, port = FTP_PORT) if @debug_mode print "connect: ", host, ", ", port, "\n" end synchronize do @host = host @bare_sock = open_socket(host, port) @sock = BufferedSocket.new(@bare_sock, read_timeout: @read_timeout) voidresp if @ssl_context begin voidcmd("AUTH TLS") ssl_sock = start_tls_session(@bare_sock) @sock = BufferedSSLSocket.new(ssl_sock, read_timeout: @read_timeout) if @private_data_connection voidcmd("PBSZ 0") voidcmd("PROT P") end rescue OpenSSL::SSL::SSLError, OpenTimeout @sock.close raise end end end end
Deletes a file on the server.
# File net/ftp.rb, line 1137 def delete(filename) resp = sendcmd("DELE #{filename}") if resp.start_with?("250") return elsif resp.start_with?("5") raise FTPPermError, resp else raise FTPReplyError, resp end end
Issues a FEAT command
Returns an array of supported optional features
# File net/ftp.rb, line 1310 def features resp = sendcmd("FEAT") if !resp.start_with?("211") raise FTPReplyError, resp end feats = [] resp.split("\n").each do |line| next if !line.start_with?(' ') # skip status lines feats << line.strip end return feats end
Retrieves remotefile
in whatever mode the session is set (text
or binary). See gettextfile
and getbinaryfile.
# File net/ftp.rb, line 812 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
Retrieves remotefile
in binary mode, storing the result in
localfile
. If localfile
is nil, returns retrieved
data. If a block is supplied, it is passed the retrieved data in
blocksize
chunks.
# File net/ftp.rb, line 751 def getbinaryfile(remotefile, localfile = File.basename(remotefile), blocksize = DEFAULT_BLOCKSIZE, &block) # :yield: data f = nil result = nil if localfile if @resume rest_offset = File.size?(localfile) f = File.open(localfile, "a") else rest_offset = nil f = File.open(localfile, "w") end elsif !block_given? result = String.new end begin f&.binmode retrbinary("RETR #{remotefile}", blocksize, rest_offset) do |data| f&.write(data) block&.(data) result&.concat(data) end return result ensure f&.close end end
Retrieves remotefile
in ASCII (text) mode, storing the result
in localfile
. If localfile
is nil, returns
retrieved data. If a block is supplied, it is passed the retrieved data one
line at a time.
# File net/ftp.rb, line 786 def gettextfile(remotefile, localfile = File.basename(remotefile), &block) # :yield: line f = nil result = nil if localfile f = File.open(localfile, "w") elsif !block_given? result = String.new end begin retrlines("RETR #{remotefile}") do |line, newline| l = newline ? line + "\n" : line f&.print(l) block&.(line, newline) result&.concat(l) end return result ensure f&.close end end
Issues the HELP command.
# File net/ftp.rb, line 1273 def help(arg = nil) cmd = "HELP" if arg cmd = cmd + " " + arg end sendcmd(cmd) end
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.
# File net/ftp.rb, line 907 def list(*args, &block) # :yield: line cmd = "LIST" args.each do |arg| cmd = "#{cmd} #{arg}" end lines = [] retrlines(cmd) do |line| lines << line end if block lines.each(&block) end return lines end
Logs in to the remote host. The session must have been previously
connected. If user
is the string “anonymous” and the
password
is nil
, “anonymous@” is used as a
password. If the acct
parameter is not nil
, an
FTP ACCT command is sent following the successful
login. Raises an exception on error (typically
Net::FTPPermError
).
# File net/ftp.rb, line 598 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.start_with?("3") raise FTPReplyError, resp if passwd.nil? resp = sendcmd('PASS ' + passwd) end if resp.start_with?("3") raise FTPReplyError, resp if acct.nil? resp = sendcmd('ACCT ' + acct) end end if !resp.start_with?("2") raise FTPReplyError, resp end @welcome = resp send_type_command @logged_in = true end
Returns the raw last modification time of the (remote) file in the format “YYYYMMDDhhmmss” (MDTM command).
Use mtime
if you want a parsed Time instance.
# File net/ftp.rb, line 1263 def mdtm(filename) resp = sendcmd("MDTM #{filename}") if resp.start_with?("213") return get_body(resp) end end
Creates a remote directory.
# File net/ftp.rb, line 1195 def mkdir(dirname) resp = sendcmd("MKD #{dirname}") return parse257(resp) end
Returns an array of the entries of the directory specified by
pathname
. Each entry has the facts (e.g., size, last
modification time, etc.) and the pathname. If a block is given, it iterates
through the listing. If pathname
is omitted, the current
directory is assumed.
# File net/ftp.rb, line 1111 def mlsd(pathname = nil, &block) # :yield: entry cmd = pathname ? "MLSD #{pathname}" : "MLSD" entries = [] retrlines(cmd) do |line| entries << parse_mlsx_entry(line) end if block entries.each(&block) end return entries end
Returns data (e.g., size, last modification time, entry type, etc.) about
the file or directory specified by pathname
. If
pathname
is omitted, the current directory is assumed.
# File net/ftp.rb, line 1089 def mlst(pathname = nil) cmd = pathname ? "MLST #{pathname}" : "MLST" resp = sendcmd(cmd) if !resp.start_with?("250") raise FTPReplyError, resp end line = resp.lines[1] unless line raise FTPProtoError, resp end entry = line.sub(/\A(250-| *)/, "") return parse_mlsx_entry(entry) end
Returns the last modification time of the (remote) file. If
local
is true
, it is returned as a local time,
otherwise it’s a UTC time.
# File net/ftp.rb, line 1188 def mtime(filename, local = false) return TIME_PARSER.(mdtm(filename), local) end
Returns an array of filenames in the remote directory.
# File net/ftp.rb, line 891 def nlst(dir = nil) cmd = "NLST" if dir cmd = "#{cmd} #{dir}" end files = [] retrlines(cmd) do |line| files.push(line) end return files end
Issues a NOOP command.
Does nothing except return a response.
# File net/ftp.rb, line 1293 def noop voidcmd("NOOP") end
Issues an OPTS command
name Should be the name of the option to set
params is any optional parameters to supply with the option
example: option(‘UTF8’, ‘ON’) => ‘OPTS UTF8 ON’
# File net/ftp.rb, line 1333 def option(name, params = nil) cmd = "OPTS #{name}" cmd += " #{params}" if params voidcmd(cmd) end
Transfers localfile
to the server in whatever mode the session
is set (text or binary). See puttextfile and putbinaryfile.
# File net/ftp.rb, line 868 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
Transfers localfile
to the server in binary mode, storing the
result in remotefile
. If a block is supplied, calls it,
passing in the transmitted data in blocksize
chunks.
# File net/ftp.rb, line 826 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 = File.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
Transfers localfile
to 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 net/ftp.rb, line 855 def puttextfile(localfile, remotefile = File.basename(localfile), &block) # :yield: line f = File.open(localfile) begin storlines("STOR #{remotefile}", f, &block) ensure f.close end end
Returns the current remote directory.
# File net/ftp.rb, line 1210 def pwd resp = sendcmd("PWD") return parse257(resp) end
Exits the FTP session.
# File net/ftp.rb, line 1284 def quit voidcmd("QUIT") end
Setter for the #read_timeout attribute.
# File net/ftp.rb, line 128 def read_timeout=(sec) @sock.read_timeout = sec @read_timeout = sec end
Renames a file on the server.
# File net/ftp.rb, line 1126 def rename(fromname, toname) resp = sendcmd("RNFR #{fromname}") if !resp.start_with?("3") raise FTPReplyError, resp end voidcmd("RNTO #{toname}") end
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
blocksize
characters. Note that cmd
is a server
command (such as “RETR myfile”).
# File net/ftp.rb, line 629 def retrbinary(cmd, blocksize, rest_offset = nil) # :yield: data synchronize do with_binary(true) do begin conn = transfercmd(cmd, rest_offset) while data = conn.read(blocksize) yield(data) end conn.shutdown(Socket::SHUT_WR) conn.read_timeout = 1 conn.read ensure conn.close if conn end voidresp end end end
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 cmd
is a server
command (such as “RETR myfile”).
# File net/ftp.rb, line 654 def retrlines(cmd) # :yield: line synchronize do with_binary(false) do begin conn = transfercmd(cmd) while line = conn.gets yield(line.sub(/\r?\n\z/, ""), !line.match(/\n\z/).nil?) end conn.shutdown(Socket::SHUT_WR) conn.read_timeout = 1 conn.read ensure conn.close if conn end voidresp end end end
Removes a remote directory.
# File net/ftp.rb, line 1203 def rmdir(dirname) voidcmd("RMD #{dirname}") end
Sends a command and returns the response.
# File net/ftp.rb, line 491 def sendcmd(cmd) synchronize do putline(cmd) return getresp end end
Set the socket used to connect to the FTP server.
May raise FTPReplyError if get_greeting
is false.
# File net/ftp.rb, line 396 def set_socket(sock, get_greeting = true) synchronize do @sock = sock if get_greeting voidresp end end end
Issues a SITE command.
# File net/ftp.rb, line 1300 def site(arg) cmd = "SITE " + arg voidcmd(cmd) end
Returns the size of the given (remote) filename.
# File net/ftp.rb, line 1174 def size(filename) with_binary(true) do resp = sendcmd("SIZE #{filename}") if !resp.start_with?("213") raise FTPReplyError, resp end return get_body(resp).to_i end end
Returns the status (STAT command).
when stat is invoked with pathname as a parameter it acts like list but a lot faster and over the same tcp session.
# File net/ftp.rb, line 1247 def status(pathname = nil) line = pathname ? "STAT #{pathname}" : "STAT" if /[\r\n]/ =~ line raise ArgumentError, "A line must not contain CR or LF" end print "put: #{line}\n" if @debug_mode @sock.send(line + CRLF, Socket::MSG_OOB) return getresp end
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
file
to the server. If the optional block is given, it also
passes it the data, in chunks of blocksize
characters.
# File net/ftp.rb, line 679 def storbinary(cmd, file, blocksize, rest_offset = nil) # :yield: data if rest_offset file.seek(rest_offset, IO::SEEK_SET) end synchronize do with_binary(true) do begin conn = transfercmd(cmd) while buf = file.read(blocksize) conn.write(buf) yield(buf) if block_given? end conn.shutdown(Socket::SHUT_WR) conn.read_timeout = 1 conn.read ensure conn.close if conn end 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
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
file
to the server, one line at a time. If the optional block
is given, it also passes it the lines.
# File net/ftp.rb, line 715 def storlines(cmd, file) # :yield: line synchronize do with_binary(false) do begin conn = transfercmd(cmd) while buf = file.gets if buf[-2, 2] != CRLF buf = buf.chomp + CRLF end conn.write(buf) yield(buf) if block_given? end conn.shutdown(Socket::SHUT_WR) conn.read_timeout = 1 conn.read ensure conn.close if conn end 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