ftplib — FTP protocol client

Source code: Lib/ftplib.py

This module defines the class FTP and a few related items. The FTP class implements the client side of the FTP protocol. You can use this to write Python programs that perform a variety of automated FTP jobs, such as mirroring other FTP servers. It is also used by the module urllib.request to handle URLs that use FTP. For more information on FTP (File Transfer Protocol), see internet RFC 959.

The default encoding is UTF-8, following RFC 2640.

Availability: not WASI.

This module does not work or is not available on WebAssembly. See WebAssembly platforms for more information.

Here’s a sample session using the ftplib module:

>>> from ftplib import FTP
>>> ftp = FTP('ftp.us.debian.org')  # connect to host, default port
>>> ftp.login()                     # user anonymous, passwd anonymous@
'230 Login successful.'
>>> ftp.cwd('debian')               # change into "debian" directory
'250 Directory successfully changed.'
>>> ftp.retrlines('LIST')           # list directory contents
-rw-rw-r--    1 1176     1176         1063 Jun 15 10:18 README
...
drwxr-sr-x    5 1176     1176         4096 Dec 19  2000 pool
drwxr-sr-x    4 1176     1176         4096 Nov 17  2008 project
drwxr-xr-x    3 1176     1176         4096 Oct 10  2012 tools
'226 Directory send OK.'
>>> with open('README', 'wb') as fp:
>>>     ftp.retrbinary('RETR README', fp.write)
'226 Transfer complete.'
>>> ftp.quit()
'221 Goodbye.'

Reference

FTP objects

class ftplib.FTP(host='', user='', passwd='', acct='', timeout=None, source_address=None, *, encoding='utf-8')

Return a new instance of the FTP class.

Parametry:

  • host (str) – The hostname to connect to. If given, connect(host) is implicitly called by the constructor.

  • user (str) – The username to log in with (default: 'anonymous'). If given, login(host, passwd, acct) is implicitly called by the constructor.

  • passwd (str) – The password to use when logging in. If not given, and if passwd is the empty string or "-", a password will be automatically generated.

  • acct (str) – Account information to be used for the ACCT FTP command. Few systems implement this. See RFC-959 for more details.

  • timeout (float | None) – A timeout in seconds for blocking operations like connect() (default: the global default timeout setting).

  • source_address (tuple | None) – A 2-tuple (host, port) for the socket to bind to as its source address before connecting.

  • encoding (str) – The encoding for directories and filenames (default: 'utf-8').

The FTP class supports the with statement, e.g.:

>>> from ftplib import FTP
>>> with FTP("ftp1.at.proftpd.org") as ftp:
...     ftp.login()
...     ftp.dir()
... 
'230 Anonymous login ok, restrictions apply.'
dr-xr-xr-x   9 ftp      ftp           154 May  6 10:43 .
dr-xr-xr-x   9 ftp      ftp           154 May  6 10:43 ..
dr-xr-xr-x   5 ftp      ftp          4096 May  6 10:43 CentOS
dr-xr-xr-x   3 ftp      ftp            18 Jul 10  2008 Fedora
>>>

Zmienione w wersji 3.2: Support for the with statement was added.

Zmienione w wersji 3.3: source_address parameter was added.

Zmienione w wersji 3.9: If the timeout parameter is set to be zero, it will raise a ValueError to prevent the creation of a non-blocking socket. The encoding parameter was added, and the default was changed from Latin-1 to UTF-8 to follow RFC 2640.

Several FTP methods are available in two flavors: one for handling text files and another for binary files. The methods are named for the command which is used followed by lines for the text version or binary for the binary version.

FTP instances have the following methods:

set_debuglevel(level)

Set the instance’s debugging level as an int. This controls the amount of debugging output printed. The debug levels are:

  • 0 (default): No debug output.

  • 1: Produce a moderate amount of debug output, generally a single line per request.

  • 2 or higher: Produce the maximum amount of debugging output, logging each line sent and received on the control connection.

connect(host='', port=0, timeout=None, source_address=None)

Connect to the given host and port. This function should be called only once for each instance; it should not be called if a host argument was given when the FTP instance was created. All other FTP methods can only be called after a connection has successfully been made.

Parametry:

  • host (str) – The host to connect to.

  • port (int) – The TCP port to connect to (default: 21, as specified by the FTP protocol specification). It is rarely needed to specify a different port number.

  • timeout (float | None) – A timeout in seconds for the connection attempt (default: the global default timeout setting).

  • source_address (tuple | None) – A 2-tuple (host, port) for the socket to bind to as its source address before connecting.

Raises an auditing event ftplib.connect with arguments self, host, port.

Zmienione w wersji 3.3: source_address parameter was added.

getwelcome()

Return the welcome message sent by the server in reply to the initial connection. (This message sometimes contains disclaimers or help information that may be relevant to the user.)

login(user='anonymous', passwd='', acct='')

Log on to the connected FTP server. This function should be called only once for each instance, after a connection has been established; it should not be called if the host and user arguments were given when the FTP instance was created. Most FTP commands are only allowed after the client has logged in.

Parametry:

  • user (str) – The username to log in with (default: 'anonymous').

  • passwd (str) – The password to use when logging in. If not given, and if passwd is the empty string or "-", a password will be automatically generated.

  • acct (str) – Account information to be used for the ACCT FTP command. Few systems implement this. See RFC-959 for more details.

abort()

Abort a file transfer that is in progress. Using this does not always work, but it’s worth a try.

sendcmd(cmd)

Send a simple command string to the server and return the response string.

Raises an auditing event ftplib.sendcmd with arguments self, cmd.

voidcmd(cmd)

Send a simple command string to the server and handle the response. Return the response string if the response code corresponds to success (codes in the range 200–299). Raise error_reply otherwise.

Raises an auditing event ftplib.sendcmd with arguments self, cmd.

retrbinary(cmd, callback, blocksize=8192, rest=None)

Retrieve a file in binary transfer mode.

Parametry:

  • cmd (str) – An appropriate RETR command: "RETR filename".

  • callback (callable) – A single parameter callable that is called for each block of data received, with its single argument being the data as bytes.

  • blocksize (int) – The maximum chunk size to read on the low-level socket object created to do the actual transfer. This also corresponds to the largest size of data that will be passed to callback. Defaults to 8192.

  • rest (int) – A REST command to be sent to the server. See the documentation for the rest parameter of the transfercmd() method.

retrlines(cmd, callback=None)

Retrieve a file or directory listing in the encoding specified by the encoding parameter at initialization. cmd should be an appropriate RETR command (see retrbinary()) or a command such as LIST or NLST (usually just the string 'LIST'). LIST retrieves a list of files and information about those files. NLST retrieves a list of file names. The callback function is called for each line with a string argument containing the line with the trailing CRLF stripped. The default callback prints the line to sys.stdout.

set_pasv(val)

Enable „passive” mode if val is true, otherwise disable passive mode. Passive mode is on by default.

storbinary(cmd, fp, blocksize=8192, callback=None, rest=None)

Store a file in binary transfer mode.

Parametry:

  • cmd (str) – An appropriate STOR command: "STOR filename".

  • fp (file object) – A file object (opened in binary mode) which is read until EOF, using its read() method in blocks of size blocksize to provide the data to be stored.

  • blocksize (int) – The read block size. Defaults to 8192.

  • callback (callable) – A single parameter callable that is called for each block of data sent, with its single argument being the data as bytes.

  • rest (int) – A REST command to be sent to the server. See the documentation for the rest parameter of the transfercmd() method.

Zmienione w wersji 3.2: The rest parameter was added.

storlines(cmd, fp, callback=None)

Store a file in line mode. cmd should be an appropriate STOR command (see storbinary()). Lines are read until EOF from the file object fp (opened in binary mode) using its readline() method to provide the data to be stored. callback is an optional single parameter callable that is called on each line after it is sent.

transfercmd(cmd, rest=None)

Initiate a transfer over the data connection. If the transfer is active, send an EPRT or PORT command and the transfer command specified by cmd, and accept the connection. If the server is passive, send an EPSV or PASV command, connect to it, and start the transfer command. Either way, return the socket for the connection.

If optional rest is given, a REST command is sent to the server, passing rest as an argument. rest is usually a byte offset into the requested file, telling the server to restart sending the file’s bytes at the requested offset, skipping over the initial bytes. Note however that the transfercmd() method converts rest to a string with the encoding parameter specified at initialization, but no check is performed on the string’s contents. If the server does not recognize the REST command, an error_reply exception will be raised. If this happens, simply call transfercmd() without a rest argument.

ntransfercmd(cmd, rest=None)

Like transfercmd(), but returns a tuple of the data connection and the expected size of the data. If the expected size could not be computed, None will be returned as the expected size. cmd and rest means the same thing as in transfercmd().

mlsd(path='', facts=[])

List a directory in a standardized format by using MLSD command (RFC 3659). If path is omitted the current directory is assumed. facts is a list of strings representing the type of information desired (e.g. ["type", "size", "perm"]). Return a generator object yielding a tuple of two elements for every file found in path. First element is the file name, the second one is a dictionary containing facts about the file name. Content of this dictionary might be limited by the facts argument but server is not guaranteed to return all requested facts.

Added in version 3.3.

nlst(argument[, ...])

Return a list of file names as returned by the NLST command. The optional argument is a directory to list (default is the current server directory). Multiple arguments can be used to pass non-standard options to the NLST command.

Informacja

If your server supports the command, mlsd() offers a better API.

dir(argument[, ...])

Produce a directory listing as returned by the LIST command, printing it to standard output. The optional argument is a directory to list (default is the current server directory). Multiple arguments can be used to pass non-standard options to the LIST command. If the last argument is a function, it is used as a callback function as for retrlines(); the default prints to sys.stdout. This method returns None.

Informacja

If your server supports the command, mlsd() offers a better API.

rename(fromname, toname)

Rename file fromname on the server to toname.

delete(filename)

Remove the file named filename from the server. If successful, returns the text of the response, otherwise raises error_perm on permission errors or error_reply on other errors.

cwd(pathname)

Set the current directory on the server.

mkd(pathname)

Create a new directory on the server.

pwd()

Return the pathname of the current directory on the server.

rmd(dirname)

Remove the directory named dirname on the server.

size(filename)

Request the size of the file named filename on the server. On success, the size of the file is returned as an integer, otherwise None is returned. Note that the SIZE command is not standardized, but is supported by many common server implementations.

quit()

Send a QUIT command to the server and close the connection. This is the „polite” way to close a connection, but it may raise an exception if the server responds with an error to the QUIT command. This implies a call to the close() method which renders the FTP instance useless for subsequent calls (see below).

close()

Close the connection unilaterally. This should not be applied to an already closed connection such as after a successful call to quit(). After this call the FTP instance should not be used any more (after a call to close() or quit() you cannot reopen the connection by issuing another login() method).

FTP_TLS objects

class ftplib.FTP_TLS(host='', user='', passwd='', acct='', *, context=None, timeout=None, source_address=None, encoding='utf-8')

An FTP subclass which adds TLS support to FTP as described in RFC 4217. Connect to port 21 implicitly securing the FTP control connection before authenticating.

Informacja

The user must explicitly secure the data connection by calling the prot_p() method.

Parametry:

  • host (str) – The hostname to connect to. If given, connect(host) is implicitly called by the constructor.

  • user (str) – The username to log in with (default: 'anonymous'). If given, login(host, passwd, acct) is implicitly called by the constructor.

  • passwd (str) – The password to use when logging in. If not given, and if passwd is the empty string or "-", a password will be automatically generated.

  • acct (str) – Account information to be used for the ACCT FTP command. Few systems implement this. See RFC-959 for more details.

  • context (ssl.SSLContext) – An SSL context object which allows bundling SSL configuration options, certificates and private keys into a single, potentially long-lived, structure. Please read Security considerations for best practices.

  • timeout (float | None) – A timeout in seconds for blocking operations like connect() (default: the global default timeout setting).

  • source_address (tuple | None) – A 2-tuple (host, port) for the socket to bind to as its source address before connecting.

  • encoding (str) – The encoding for directories and filenames (default: 'utf-8').

Added in version 3.2.

Zmienione w wersji 3.3: Added the source_address parameter.

Zmienione w wersji 3.4: The class now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI).

Zmienione w wersji 3.9: If the timeout parameter is set to be zero, it will raise a ValueError to prevent the creation of a non-blocking socket. The encoding parameter was added, and the default was changed from Latin-1 to UTF-8 to follow RFC 2640.

Zmienione w wersji 3.12: The deprecated keyfile and certfile parameters have been removed.

Here’s a sample session using the FTP_TLS class:

>>> ftps = FTP_TLS('ftp.pureftpd.org')
>>> ftps.login()
'230 Anonymous user logged in'
>>> ftps.prot_p()
'200 Data protection level set to "private"'
>>> ftps.nlst()
['6jack', 'OpenBSD', 'antilink', 'blogbench', 'bsdcam', 'clockspeed', 'djbdns-jedi', 'docs', 'eaccelerator-jedi', 'favicon.ico', 'francotone', 'fugu', 'ignore', 'libpuzzle', 'metalog', 'minidentd', 'misc', 'mysql-udf-global-user-variables', 'php-jenkins-hash', 'php-skein-hash', 'php-webdav', 'phpaudit', 'phpbench', 'pincaster', 'ping', 'posto', 'pub', 'public', 'public_keys', 'pure-ftpd', 'qscan', 'qtc', 'sharedance', 'skycache', 'sound', 'tmp', 'ucarp']

FTP_TLS class inherits from FTP, defining these additional methods and attributes:

ssl_version

The SSL version to use (defaults to ssl.PROTOCOL_SSLv23).

auth()

Set up a secure control connection by using TLS or SSL, depending on what is specified in the ssl_version attribute.

Zmienione w wersji 3.4: The method now supports hostname check with ssl.SSLContext.check_hostname and Server Name Indication (see ssl.HAS_SNI).

ccc()

Revert control channel back to plaintext. This can be useful to take advantage of firewalls that know how to handle NAT with non-secure FTP without opening fixed ports.

Added in version 3.3.

prot_p()

Set up secure data connection.

prot_c()

Set up clear text data connection.

Module variables

exception ftplib.error_reply

Exception raised when an unexpected reply is received from the server.

exception ftplib.error_temp

Exception raised when an error code signifying a temporary error (response codes in the range 400–499) is received.

exception ftplib.error_perm

Exception raised when an error code signifying a permanent error (response codes in the range 500–599) is received.

exception ftplib.error_proto

Exception raised when a reply is received from the server that does not fit the response specifications of the File Transfer Protocol, i.e. begin with a digit in the range 1–5.

ftplib.all_errors

The set of all exceptions (as a tuple) that methods of FTP instances may raise as a result of problems with the FTP connection (as opposed to programming errors made by the caller). This set includes the four exceptions listed above as well as OSError and EOFError.

Zobacz także

Module netrc

Parser for the .netrc file format. The file .netrc is typically used by FTP clients to load user authentication information before prompting the user.