ftplib.py

"""An FTP client class and some helper functions.

Based on RFC 959: File Transfer Protocol (FTP), by J. Postel and J. Reynolds

Example:

>>> from ftplib import FTP
>>> ftp = FTP('ftp.python.org') # connect to host, default port
>>> ftp.login() # default, i.e.: user anonymous, passwd anonymous@
'230 Guest login ok, access restrictions apply.'
>>> ftp.retrlines('LIST') # list directory contents
total 9
drwxr-xr-x 8 root wheel 1024 Jan 3 1994 .
drwxr-xr-x 8 root wheel 1024 Jan 3 1994 ..
drwxr-xr-x 2 root wheel 1024 Jan 3 1994 bin
drwxr-xr-x 2 root wheel 1024 Jan 3 1994 etc
d-wxrwxr-x 2 ftp wheel 1024 Sep 5 13:43 incoming
drwxr-xr-x 2 root wheel 1024 Nov 17 1993 lib
drwxr-xr-x 6 1094 wheel 1024 Sep 13 19:07 pub
drwxr-xr-x 3 root wheel 1024 Jan 3 1994 usr
-rw-r--r-- 1 root root 312 Aug 1 1994 welcome.msg
'226 Transfer complete.'
>>> ftp.quit()
'221 Goodbye.'
>>>

A nice test that reveals some of the network dialogue would be:
python ftplib.py -d localhost -l -p -l
"""

#
# Changes and improvements suggested by Steve Majewski.
# Modified by Jack to work on the mac.
# Modified by Siebren to support docstrings and PASV.
# Modified by Phil Schwartz to add storbinary and storlines callbacks.
# Modified by Giampaolo Rodola' to add TLS support.
#

importsys
importsocket
fromsocketimport_GLOBAL_DEFAULT_TIMEOUT

__all__= ["FTP", "error_reply", "error_temp", "error_perm", "error_proto",
"all_errors"]

# Magic number from <socket.h>
MSG_OOB=0x1# Process data out of band


# The standard FTP server control port
FTP_PORT=21
# The sizehint parameter passed to readline() calls
MAXLINE=8192


# Exception raised when an error or invalid response is received
classError(Exception): pass
classerror_reply(Error): pass# unexpected [123]xx reply
classerror_temp(Error): pass# 4xx errors
classerror_perm(Error): pass# 5xx errors
classerror_proto(Error): pass# response does not begin with [1-5]


# All exceptions (hopefully) that may be raised here and that aren't
# (always) programming errors on our side
all_errors= (Error, OSError, EOFError)


# Line terminators (we always output CRLF, but accept any of CRLF, CR, LF)
CRLF='\r\n'
B_CRLF=b'\r\n'

# The class itself
classFTP:

'''An FTP client class.

 To create a connection, call the class using these arguments:
 host, user, passwd, acct, timeout

 The first four arguments are all strings, and have default value ''.
 timeout must be numeric and defaults to None if not passed,
 meaning that no timeout will be set on any ftp socket(s)
 If a timeout is passed, then this is now the default timeout for all ftp
 socket operations for this instance.

 Then use self.connect() with optional host and port argument.

 To download a file, use ftp.retrlines('RETR ' + filename),
 or ftp.retrbinary() with slightly different arguments.
 To upload a file, use ftp.storlines() or ftp.storbinary(),
 which have an open file as argument (see their definitions
 below for details).
 The download/upload functions first issue appropriate TYPE
 and PORT or PASV commands.
 '''

debugging=0
host=''
port=FTP_PORT
maxline=MAXLINE
sock=None
file=None
welcome=None
passiveserver=1
encoding="latin-1"

# Initialization method (called by class instantiation).
# Initialize host to localhost, port to standard ftp port
# Optional arguments are host (for connect()),
# and user, passwd, acct (for login())
def__init__(self, host='', user='', passwd='', acct='',
timeout=_GLOBAL_DEFAULT_TIMEOUT, source_address=None):
self.source_address=source_address
self.timeout=timeout
ifhost:
self.connect(host)
ifuser:
self.login(user, passwd, acct)

def__enter__(self):
returnself

# Context management protocol: try to quit() if active
def__exit__(self, *args):
ifself.sockisnotNone:
try:
self.quit()
except (OSError, EOFError):
pass
finally:
ifself.sockisnotNone:
self.close()

defconnect(self, host='', port=0, timeout=-999, source_address=None):
'''Connect to host. Arguments are:
 - host: hostname to connect to (string, default previous host)
 - port: port to connect to (integer, default previous port)
 - timeout: the timeout to set against the ftp socket(s)
 - source_address: a 2-tuple (host, port) for the socket to bind
 to as its source address before connecting.
 '''
ifhost!='':
self.host=host
ifport>0:
self.port=port
iftimeout!=-999:
self.timeout=timeout
ifsource_addressisnotNone:
self.source_address=source_address
self.sock=socket.create_connection((self.host, self.port), self.timeout,
source_address=self.source_address)
self.af=self.sock.family
self.file=self.sock.makefile('r', encoding=self.encoding)
self.welcome=self.getresp()
returnself.welcome

defgetwelcome(self):
'''Get the welcome message from the server.
 (this is read and squirreled away by connect())'''
ifself.debugging:
print('*welcome*', self.sanitize(self.welcome))
returnself.welcome

defset_debuglevel(self, level):
'''Set the debugging level.
 The required argument level means:
 0: no debugging output (default)
 1: print commands and responses but not body text etc.
 2: also print raw lines read and sent before stripping CR/LF'''
self.debugging=level
debug=set_debuglevel

defset_pasv(self, val):
'''Use passive or active mode for data transfers.
 With a false argument, use the normal PORT mode,
 With a true argument, use the PASV command.'''
self.passiveserver=val

# Internal: "sanitize" a string for printing
defsanitize(self, s):
ifs[:5] in {'pass ', 'PASS '}:
i=len(s.rstrip('\r\n'))
s=s[:5] +'*'*(i-5) +s[i:]
returnrepr(s)

# Internal: send one line to the server, appending CRLF
defputline(self, line):
line=line+CRLF
ifself.debugging>1:
print('*put*', self.sanitize(line))
self.sock.sendall(line.encode(self.encoding))

# Internal: send one command to the server (through putline())
defputcmd(self, line):
ifself.debugging: print('*cmd*', self.sanitize(line))
self.putline(line)

# Internal: return one line from the server, stripping CRLF.
# Raise EOFError if the connection is closed
defgetline(self):
line=self.file.readline(self.maxline+1)
iflen(line) >self.maxline:
raiseError("got more than %d bytes"%self.maxline)
ifself.debugging>1:
print('*get*', self.sanitize(line))
ifnotline:
raiseEOFError
ifline[-2:] ==CRLF:
line=line[:-2]
elifline[-1:] inCRLF:
line=line[:-1]
returnline

# Internal: get a response from the server, which may possibly
# consist of multiple lines. Return a single string with no
# trailing CRLF. If the response consists of multiple lines,
# these are separated by '\n' characters in the string
defgetmultiline(self):
line=self.getline()
ifline[3:4] =='-':
code=line[:3]
while1:
nextline=self.getline()
line=line+ ('\n'+nextline)
ifnextline[:3] ==codeand \
nextline[3:4] !='-':
break
returnline

# Internal: get a response from the server.
# Raise various errors if the response indicates an error
defgetresp(self):
resp=self.getmultiline()
ifself.debugging:
print('*resp*', self.sanitize(resp))
self.lastresp=resp[:3]
c=resp[:1]
ifcin {'1', '2', '3'}:
returnresp
ifc=='4':
raiseerror_temp(resp)
ifc=='5':
raiseerror_perm(resp)
raiseerror_proto(resp)

defvoidresp(self):
"""Expect a response beginning with '2'."""
resp=self.getresp()
ifresp[:1] !='2':
raiseerror_reply(resp)
returnresp

defabort(self):
'''Abort a file transfer. Uses out-of-band data.
 This does not follow the procedure from the RFC to send Telnet
 IP and Synch; that doesn't seem to work with the servers I've
 tried. Instead, just send the ABOR command as OOB data.'''
line=b'ABOR'+B_CRLF
ifself.debugging>1:
print('*put urgent*', self.sanitize(line))
self.sock.sendall(line, MSG_OOB)
resp=self.getmultiline()
ifresp[:3] notin {'426', '225', '226'}:
raiseerror_proto(resp)
returnresp

defsendcmd(self, cmd):
'''Send a command and return the response.'''
self.putcmd(cmd)
returnself.getresp()

defvoidcmd(self, cmd):
"""Send a command and expect a response beginning with '2'."""
self.putcmd(cmd)
returnself.voidresp()

defsendport(self, host, port):
'''Send a PORT command with the current host and the given
 port number.
 '''
hbytes=host.split('.')
pbytes= [repr(port//256), repr(port%256)]
bytes=hbytes+pbytes
cmd='PORT '+','.join(bytes)
returnself.voidcmd(cmd)

defsendeprt(self, host, port):
'''Send an EPRT command with the current host and the given port number.'''
af=0
ifself.af==socket.AF_INET:
af=1
ifself.af==socket.AF_INET6:
af=2
ifaf==0:
raiseerror_proto('unsupported address family')
fields= ['', repr(af), host, repr(port), '']
cmd='EPRT '+'|'.join(fields)
returnself.voidcmd(cmd)

defmakeport(self):
'''Create a new socket and send a PORT command for it.'''
err=None
sock=None
forresinsocket.getaddrinfo(None, 0, self.af, socket.SOCK_STREAM, 0, socket.AI_PASSIVE):
af, socktype, proto, canonname, sa=res
try:
sock=socket.socket(af, socktype, proto)
sock.bind(sa)
exceptOSErroras_:
err=_
ifsock:
sock.close()
sock=None
continue
break
ifsockisNone:
iferrisnotNone:
raiseerr
else:
raiseOSError("getaddrinfo returns an empty list")
sock.listen(1)
port=sock.getsockname()[1] # Get proper port
host=self.sock.getsockname()[0] # Get proper host
ifself.af==socket.AF_INET:
resp=self.sendport(host, port)
else:
resp=self.sendeprt(host, port)
ifself.timeoutisnot_GLOBAL_DEFAULT_TIMEOUT:
sock.settimeout(self.timeout)
returnsock

defmakepasv(self):
ifself.af==socket.AF_INET:
host, port=parse227(self.sendcmd('PASV'))
else:
host, port=parse229(self.sendcmd('EPSV'), self.sock.getpeername())
returnhost, port

defntransfercmd(self, cmd, rest=None):
"""Initiate a transfer over the data connection.

 If the transfer is active, send a port command and the
 transfer command, and accept the connection. If the server is
 passive, send a pasv command, connect to it, and start the
 transfer command. Either way, return the socket for the
 connection and the expected size of the transfer. The
 expected size may be None if it could not be determined.

 Optional `rest' argument can be a string that is sent as the
 argument to a REST command. This is essentially a server
 marker used to tell the server to skip over any data up to the
 given marker.
 """
size=None
ifself.passiveserver:
host, port=self.makepasv()
conn=socket.create_connection((host, port), self.timeout,
source_address=self.source_address)
try:
ifrestisnotNone:
self.sendcmd("REST %s"%rest)
resp=self.sendcmd(cmd)
# Some servers apparently send a 200 reply to
# a LIST or STOR command, before the 150 reply
# (and way before the 226 reply). This seems to
# be in violation of the protocol (which only allows
# 1xx or error messages for LIST), so we just discard
# this response.
ifresp[0] =='2':
resp=self.getresp()
ifresp[0] !='1':
raiseerror_reply(resp)
except:
conn.close()
raise
else:
withself.makeport() assock:
ifrestisnotNone:
self.sendcmd("REST %s"%rest)
resp=self.sendcmd(cmd)
# See above.
ifresp[0] =='2':
resp=self.getresp()
ifresp[0] !='1':
raiseerror_reply(resp)
conn, sockaddr=sock.accept()
ifself.timeoutisnot_GLOBAL_DEFAULT_TIMEOUT:
conn.settimeout(self.timeout)
ifresp[:3] =='150':
# this is conditional in case we received a 125
size=parse150(resp)
returnconn, size

deftransfercmd(self, cmd, rest=None):
"""Like ntransfercmd() but returns only the socket."""
returnself.ntransfercmd(cmd, rest)[0]

deflogin(self, user='', passwd='', acct=''):
'''Login, default anonymous.'''
ifnotuser:
user='anonymous'
ifnotpasswd:
passwd=''
ifnotacct:
acct=''
ifuser=='anonymous'andpasswdin {'', '-'}:
# If there is no anonymous ftp password specified
# then we'll just use anonymous@
# We don't send any other thing because:
# - We want to remain anonymous
# - We want to stop SPAM
# - We don't want to let ftp sites to discriminate by the user,
# host or country.
passwd=passwd+'anonymous@'
resp=self.sendcmd('USER '+user)
ifresp[0] =='3':
resp=self.sendcmd('PASS '+passwd)
ifresp[0] =='3':
resp=self.sendcmd('ACCT '+acct)
ifresp[0] !='2':
raiseerror_reply(resp)
returnresp

defretrbinary(self, cmd, callback, blocksize=8192, rest=None):
"""Retrieve data in binary mode. A new port is created for you.

 Args:
 cmd: A RETR command.
 callback: A single parameter callable to be called on each
 block of data read.
 blocksize: The maximum number of bytes to read from the
 socket at one time. [default: 8192]
 rest: Passed to transfercmd(). [default: None]

 Returns:
 The response code.
 """
self.voidcmd('TYPE I')
withself.transfercmd(cmd, rest) asconn:
while1:
data=conn.recv(blocksize)
ifnotdata:
break
callback(data)
# shutdown ssl layer
if_SSLSocketisnotNoneandisinstance(conn, _SSLSocket):
conn.unwrap()
returnself.voidresp()

defretrlines(self, cmd, callback=None):
"""Retrieve data in line mode. A new port is created for you.

 Args:
 cmd: A RETR, LIST, or NLST command.
 callback: An optional single parameter callable that is called
 for each line with the trailing CRLF stripped.
 [default: print_line()]

 Returns:
 The response code.
 """
ifcallbackisNone:
callback=print_line
resp=self.sendcmd('TYPE A')
withself.transfercmd(cmd) asconn, \
conn.makefile('r', encoding=self.encoding) asfp:
while1:
line=fp.readline(self.maxline+1)
iflen(line) >self.maxline:
raiseError("got more than %d bytes"%self.maxline)
ifself.debugging>2:
print('*retr*', repr(line))
ifnotline:
break
ifline[-2:] ==CRLF:
line=line[:-2]
elifline[-1:] =='\n':
line=line[:-1]
callback(line)
# shutdown ssl layer
if_SSLSocketisnotNoneandisinstance(conn, _SSLSocket):
conn.unwrap()
returnself.voidresp()

defstorbinary(self, cmd, fp, blocksize=8192, callback=None, rest=None):
"""Store a file in binary mode. A new port is created for you.

 Args:
 cmd: A STOR command.
 fp: A file-like object with a read(num_bytes) method.
 blocksize: The maximum data size to read from fp and send over
 the connection at once. [default: 8192]
 callback: An optional single parameter callable that is called on
 each block of data after it is sent. [default: None]
 rest: Passed to transfercmd(). [default: None]

 Returns:
 The response code.
 """
self.voidcmd('TYPE I')
withself.transfercmd(cmd, rest) asconn:
while1:
buf=fp.read(blocksize)
ifnotbuf:
break
conn.sendall(buf)
ifcallback:
callback(buf)
# shutdown ssl layer
if_SSLSocketisnotNoneandisinstance(conn, _SSLSocket):
conn.unwrap()
returnself.voidresp()

defstorlines(self, cmd, fp, callback=None):
"""Store a file in line mode. A new port is created for you.

 Args:
 cmd: A STOR command.
 fp: A file-like object with a readline() method.
 callback: An optional single parameter callable that is called on
 each line after it is sent. [default: None]

 Returns:
 The response code.
 """
self.voidcmd('TYPE A')
withself.transfercmd(cmd) asconn:
while1:
buf=fp.readline(self.maxline+1)
iflen(buf) >self.maxline:
raiseError("got more than %d bytes"%self.maxline)
ifnotbuf:
break
ifbuf[-2:] !=B_CRLF:
ifbuf[-1] inB_CRLF: buf=buf[:-1]
buf=buf+B_CRLF
conn.sendall(buf)
ifcallback:
callback(buf)
# shutdown ssl layer
if_SSLSocketisnotNoneandisinstance(conn, _SSLSocket):
conn.unwrap()
returnself.voidresp()

defacct(self, password):
'''Send new account name.'''
cmd='ACCT '+password
returnself.voidcmd(cmd)

defnlst(self, *args):
'''Return a list of files in a given directory (default the current).'''
cmd='NLST'
forarginargs:
cmd=cmd+ (' '+arg)
files= []
self.retrlines(cmd, files.append)
returnfiles

defdir(self, *args):
'''List a directory in long form.
 By default list current directory to stdout.
 Optional last argument is callback function; all
 non-empty arguments before it are concatenated to the
 LIST command. (This *should* only be used for a pathname.)'''
cmd='LIST'
func=None
ifargs[-1:] andtype(args[-1]) !=type(''):
args, func=args[:-1], args[-1]
forarginargs:
ifarg:
cmd=cmd+ (' '+arg)
self.retrlines(cmd, func)

defmlsd(self, 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
 including a variable number of "facts" depending on the server
 and whether "facts" argument has been provided.
 '''
iffacts:
self.sendcmd("OPTS MLST "+";".join(facts) +";")
ifpath:
cmd="MLSD %s"%path
else:
cmd="MLSD"
lines= []
self.retrlines(cmd, lines.append)
forlineinlines:
facts_found, _, name=line.rstrip(CRLF).partition(' ')
entry= {}
forfactinfacts_found[:-1].split(";"):
key, _, value=fact.partition("=")
entry[key.lower()] =value
yield (name, entry)

defrename(self, fromname, toname):
'''Rename a file.'''
resp=self.sendcmd('RNFR '+fromname)
ifresp[0] !='3':
raiseerror_reply(resp)
returnself.voidcmd('RNTO '+toname)

defdelete(self, filename):
'''Delete a file.'''
resp=self.sendcmd('DELE '+filename)
ifresp[:3] in {'250', '200'}:
returnresp
else:
raiseerror_reply(resp)

defcwd(self, dirname):
'''Change to a directory.'''
ifdirname=='..':
try:
returnself.voidcmd('CDUP')
excepterror_permasmsg:
ifmsg.args[0][:3] !='500':
raise
elifdirname=='':
dirname='.'# does nothing, but could return error
cmd='CWD '+dirname
returnself.voidcmd(cmd)

defsize(self, filename):
'''Retrieve the size of a file.'''
# The SIZE command is defined in RFC-3659
resp=self.sendcmd('SIZE '+filename)
ifresp[:3] =='213':
s=resp[3:].strip()
returnint(s)

defmkd(self, dirname):
'''Make a directory, return its full pathname.'''
resp=self.voidcmd('MKD '+dirname)
# fix around non-compliant implementations such as IIS shipped
# with Windows server 2003
ifnotresp.startswith('257'):
return''
returnparse257(resp)

defrmd(self, dirname):
'''Remove a directory.'''
returnself.voidcmd('RMD '+dirname)

defpwd(self):
'''Return current working directory.'''
resp=self.voidcmd('PWD')
# fix around non-compliant implementations such as IIS shipped
# with Windows server 2003
ifnotresp.startswith('257'):
return''
returnparse257(resp)

defquit(self):
'''Quit, and close the connection.'''
resp=self.voidcmd('QUIT')
self.close()
returnresp

defclose(self):
'''Close the connection without assuming anything about it.'''
try:
file=self.file
self.file=None
iffileisnotNone:
file.close()
finally:
sock=self.sock
self.sock=None
ifsockisnotNone:
sock.close()

try:
importssl
exceptImportError:
_SSLSocket=None
else:
_SSLSocket=ssl.SSLSocket

classFTP_TLS(FTP):
'''A FTP subclass which adds TLS support to FTP as described
 in RFC-4217.

 Connect as usual to port 21 implicitly securing the FTP control
 connection before authenticating.

 Securing the data connection requires user to explicitly ask
 for it by calling prot_p() method.

 Usage example:
 >>> from ftplib import FTP_TLS
 >>> ftps = FTP_TLS('ftp.python.org')
 >>> ftps.login() # login anonymously previously securing control channel
 '230 Guest login ok, access restrictions apply.'
 >>> ftps.prot_p() # switch to secure data connection
 '200 Protection level set to P'
 >>> ftps.retrlines('LIST') # list directory content securely
 total 9
 drwxr-xr-x 8 root wheel 1024 Jan 3 1994 .
 drwxr-xr-x 8 root wheel 1024 Jan 3 1994 ..
 drwxr-xr-x 2 root wheel 1024 Jan 3 1994 bin
 drwxr-xr-x 2 root wheel 1024 Jan 3 1994 etc
 d-wxrwxr-x 2 ftp wheel 1024 Sep 5 13:43 incoming
 drwxr-xr-x 2 root wheel 1024 Nov 17 1993 lib
 drwxr-xr-x 6 1094 wheel 1024 Sep 13 19:07 pub
 drwxr-xr-x 3 root wheel 1024 Jan 3 1994 usr
 -rw-r--r-- 1 root root 312 Aug 1 1994 welcome.msg
 '226 Transfer complete.'
 >>> ftps.quit()
 '221 Goodbye.'
 >>>
 '''
ssl_version=ssl.PROTOCOL_SSLv23

def__init__(self, host='', user='', passwd='', acct='', keyfile=None,
certfile=None, context=None,
timeout=_GLOBAL_DEFAULT_TIMEOUT, source_address=None):
ifcontextisnotNoneandkeyfileisnotNone:
raiseValueError("context and keyfile arguments are mutually "
"exclusive")
ifcontextisnotNoneandcertfileisnotNone:
raiseValueError("context and certfile arguments are mutually "
"exclusive")
self.keyfile=keyfile
self.certfile=certfile
ifcontextisNone:
context=ssl._create_stdlib_context(self.ssl_version,
certfile=certfile,
keyfile=keyfile)
self.context=context
self._prot_p=False
FTP.__init__(self, host, user, passwd, acct, timeout, source_address)

deflogin(self, user='', passwd='', acct='', secure=True):
ifsecureandnotisinstance(self.sock, ssl.SSLSocket):
self.auth()
returnFTP.login(self, user, passwd, acct)

defauth(self):
'''Set up secure control connection by using TLS/SSL.'''
ifisinstance(self.sock, ssl.SSLSocket):
raiseValueError("Already using TLS")
ifself.ssl_version>=ssl.PROTOCOL_SSLv23:
resp=self.voidcmd('AUTH TLS')
else:
resp=self.voidcmd('AUTH SSL')
self.sock=self.context.wrap_socket(self.sock,
server_hostname=self.host)
self.file=self.sock.makefile(mode='r', encoding=self.encoding)
returnresp

defccc(self):
'''Switch back to a clear-text control connection.'''
ifnotisinstance(self.sock, ssl.SSLSocket):
raiseValueError("not using TLS")
resp=self.voidcmd('CCC')
self.sock=self.sock.unwrap()
returnresp

defprot_p(self):
'''Set up secure data connection.'''
# PROT defines whether or not the data channel is to be protected.
# Though RFC-2228 defines four possible protection levels,
# RFC-4217 only recommends two, Clear and Private.
# Clear (PROT C) means that no security is to be used on the
# data-channel, Private (PROT P) means that the data-channel
# should be protected by TLS.
# PBSZ command MUST still be issued, but must have a parameter of
# '0' to indicate that no buffering is taking place and the data
# connection should not be encapsulated.
self.voidcmd('PBSZ 0')
resp=self.voidcmd('PROT P')
self._prot_p=True
returnresp

defprot_c(self):
'''Set up clear text data connection.'''
resp=self.voidcmd('PROT C')
self._prot_p=False
returnresp

# --- Overridden FTP methods

defntransfercmd(self, cmd, rest=None):
conn, size=FTP.ntransfercmd(self, cmd, rest)
ifself._prot_p:
conn=self.context.wrap_socket(conn,
server_hostname=self.host)
returnconn, size

defabort(self):
# overridden as we can't pass MSG_OOB flag to sendall()
line=b'ABOR'+B_CRLF
self.sock.sendall(line)
resp=self.getmultiline()
ifresp[:3] notin {'426', '225', '226'}:
raiseerror_proto(resp)
returnresp

__all__.append('FTP_TLS')
all_errors= (Error, OSError, EOFError, ssl.SSLError)


_150_re=None

defparse150(resp):
'''Parse the '150' response for a RETR request.
 Returns the expected transfer size or None; size is not guaranteed to
 be present in the 150 message.
 '''
ifresp[:3] !='150':
raiseerror_reply(resp)
global_150_re
if_150_reisNone:
importre
_150_re=re.compile(
"150 .* \((\d+) bytes\)", re.IGNORECASE|re.ASCII)
m=_150_re.match(resp)
ifnotm:
returnNone
returnint(m.group(1))


_227_re=None

defparse227(resp):
'''Parse the '227' response for a PASV request.
 Raises error_proto if it does not contain '(h1,h2,h3,h4,p1,p2)'
 Return ('host.addr.as.numbers', port#) tuple.'''

ifresp[:3] !='227':
raiseerror_reply(resp)
global_227_re
if_227_reisNone:
importre
_227_re=re.compile(r'(\d+),(\d+),(\d+),(\d+),(\d+),(\d+)', re.ASCII)
m=_227_re.search(resp)
ifnotm:
raiseerror_proto(resp)
numbers=m.groups()
host='.'.join(numbers[:4])
port= (int(numbers[4]) <<8) +int(numbers[5])
returnhost, port


defparse229(resp, peer):
'''Parse the '229' response for an EPSV request.
 Raises error_proto if it does not contain '(|||port|)'
 Return ('host.addr.as.numbers', port#) tuple.'''

ifresp[:3] !='229':
raiseerror_reply(resp)
left=resp.find('(')
ifleft<0: raiseerror_proto(resp)
right=resp.find(')', left+1)
ifright<0:
raiseerror_proto(resp) # should contain '(|||port|)'
ifresp[left+1] !=resp[right-1]:
raiseerror_proto(resp)
parts=resp[left+1:right].split(resp[left+1])
iflen(parts) !=5:
raiseerror_proto(resp)
host=peer[0]
port=int(parts[3])
returnhost, port


defparse257(resp):
'''Parse the '257' response for a MKD or PWD request.
 This is a response to a MKD or PWD request: a directory name.
 Returns the directoryname in the 257 reply.'''

ifresp[:3] !='257':
raiseerror_reply(resp)
ifresp[3:5] !=' "':
return''# Not compliant to RFC 959, but UNIX ftpd does this
dirname=''
i=5
n=len(resp)
whilei<n:
c=resp[i]
i=i+1
ifc=='"':
ifi>=norresp[i] !='"':
break
i=i+1
dirname=dirname+c
returndirname


defprint_line(line):
'''Default retrlines callback to print a line.'''
print(line)


defftpcp(source, sourcename, target, targetname='', type='I'):
'''Copy file from one FTP-instance to another.'''
ifnottargetname:
targetname=sourcename
type='TYPE '+type
source.voidcmd(type)
target.voidcmd(type)
sourcehost, sourceport=parse227(source.sendcmd('PASV'))
target.sendport(sourcehost, sourceport)
# RFC 959: the user must "listen" [...] BEFORE sending the
# transfer request.
# So: STOR before RETR, because here the target is a "user".
treply=target.sendcmd('STOR '+targetname)
iftreply[:3] notin {'125', '150'}:
raiseerror_proto# RFC 959
sreply=source.sendcmd('RETR '+sourcename)
ifsreply[:3] notin {'125', '150'}:
raiseerror_proto# RFC 959
source.voidresp()
target.voidresp()


deftest():
'''Test program.
 Usage: ftp [-d] [-r[file]] host [-l[dir]] [-d[dir]] [-p] [file] ...

 -d dir
 -l list
 -p password
 '''

iflen(sys.argv) <2:
print(test.__doc__)
sys.exit(0)

importnetrc

debugging=0
rcfile=None
whilesys.argv[1] =='-d':
debugging=debugging+1
delsys.argv[1]
ifsys.argv[1][:2] =='-r':
# get name of alternate ~/.netrc file:
rcfile=sys.argv[1][2:]
delsys.argv[1]
host=sys.argv[1]
ftp=FTP(host)
ftp.set_debuglevel(debugging)
userid=passwd=acct=''
try:
netrcobj=netrc.netrc(rcfile)
exceptOSError:
ifrcfileisnotNone:
sys.stderr.write("Could not open account file"
" -- using anonymous login.")
else:
try:
userid, acct, passwd=netrcobj.authenticators(host)
exceptKeyError:
# no account for host
sys.stderr.write(
"No account -- using anonymous login.")
ftp.login(userid, passwd, acct)
forfileinsys.argv[2:]:
iffile[:2] =='-l':
ftp.dir(file[2:])
eliffile[:2] =='-d':
cmd='CWD'
iffile[2:]: cmd=cmd+' '+file[2:]
resp=ftp.sendcmd(cmd)
eliffile=='-p':
ftp.set_pasv(notftp.passiveserver)
else:
ftp.retrbinary('RETR '+file, \
sys.stdout.write, 1024)
ftp.quit()


if__name__=='__main__':
test()