# -*- coding: utf-8 -*-
##############################################################################
#
# Copyright (c) 2013 Nexedi SARL and Contributors. All Rights Reserved.
# Aurélien Calonne <aurel@nexedi.com>
#
# WARNING: This program as such is intended to be used by professional
# programmers who take the whole responsability of assessing all potential
# consequences resulting from its eventual inadequacies and bugs
# End users who are looking for a ready-to-use solution with commercial
# garantees and support are strongly adviced to contract a Free Software
# Service Company
#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
##############################################################################
import os, socket
import operator
from six.moves.urllib.parse import urlparse
from socket import gaierror, error, socket, getaddrinfo, AF_UNSPEC, SOCK_STREAM
from six.moves.xmlrpc_client import Binary
from six.moves import cStringIO as StringIO
from paramiko import Transport, RSAKey, SFTPClient
from paramiko.util import retry_on_signal
class SFTPError(Exception):
"""
Default exception for the connection
"""
pass
class SFTPConnection:
"""
Handle a SFTP (SSH over FTP) Connection
"""
def __init__(self, url, user_name, password=None, private_key=None,
bind_address=None):
self.url = url
self.user_name = user_name
if password and private_key:
raise SFTPError("Password and private_key cannot be defined simultaneously")
self.password = password
self.private_key = private_key
self.bind_address = bind_address
def connect(self):
""" Get a handle to a remote connection """
# Check URL
schema = urlparse(self.url)
if schema.scheme == 'sftp':
hostname = schema.hostname
port = int(schema.port)
# Socket creation code inspired from paramiko.Transport.__init__
# with added bind support.
for family, socktype, _, _, _ in getaddrinfo(
hostname, port, AF_UNSPEC, SOCK_STREAM,
):
if socktype == SOCK_STREAM:
sock = socket(family, SOCK_STREAM)
if self.bind_address:
# XXX: Expects bind address to be of same family as hostname.
# May not be easy if name resolution is involved.
# Try to reconciliate them ?
sock.bind((self.bind_address, 0))
retry_on_signal(lambda: sock.connect((hostname, port))) # pylint: disable=cell-var-from-loop
break
else:
raise SFTPError('No suitable socket family found')
self.transport = Transport(sock)
else:
raise SFTPError('Not a valid sftp url %s, type is %s' %(self.url, schema.scheme))
# Add authentication to transport
try:
if self.password:
self.transport.connect(username=self.user_name, password=self.password)
elif self.private_key:
self.transport.connect(username=self.user_name,
pkey=RSAKey.from_private_key(StringIO(self.private_key)))
else:
raise SFTPError("No password or private_key defined")
# Connect
self.conn = SFTPClient.from_transport(self.transport)
except (gaierror, error) as msg:
raise SFTPError(str(msg) + ' while establishing connection to %s' % (self.url,))
# Go to specified directory
try:
schema.path.rstrip('/')
if len(schema.path):
self.conn.chdir(schema.path)
except IOError as msg:
raise SFTPError(str(msg) + ' while changing to dir -%r-' % (schema.path,))
return self
def writeFile(self, path, filename, data, confirm=True):
"""
Write data in provided filepath
"""
filepath = os.path.join(path, filename)
serialized_data = Binary(str(data))
try:
self.conn.putfo(StringIO(str(serialized_data)), filepath, confirm=confirm)
except error as msg:
raise SFTPError(str(msg) + ' while writing file %s on %s' % (filepath, path))
def _getFile(self, filepath):
"""Retrieve the file"""
try:
# always open with binary mode, otherwise paramiko will raise
# UnicodeDecodeError for non-utf8 data. also SFTP has no ASCII
# mode like FTP that normalises CRLF/CR/LF.
tmp_file = self.conn.file(filepath, 'rb')
tmp_file.seek(0)
return tmp_file.read()
except error as msg:
raise SFTPError(str(msg) + ' while retrieving file %s from %s' % (filepath, self.url))
def readBinaryFile(self, filepath):
"""Retrieve the file in binary mode"""
return self._getFile(filepath)
def readAsciiFile(self, filepath):
"""Retrieve the file in ASCII mode"""
# normalise CRLF/CR/LF like FTP's ASCII mode transfer.
return os.linesep.join(self._getFile(filepath).splitlines())
def getDirectoryContent(self, path, sort_on=None):
"""retrieve all entries in a givan path as a list.
`sort_on` parameter allows to retrieve the directory content in a sorted
order, it understands all parameters from
paramiko.sftp_attr.SFTPAttributes, the most useful being `st_mtime` to sort
by modification date.
"""
try:
if sort_on:
return [x.filename for x in sorted(self.conn.listdir_attr(path), key=operator.attrgetter(sort_on))]
return self.conn.listdir(path)
except (EOFError, error) as msg:
raise SFTPError(str(msg) + ' while trying to list %s on %s' % (path, self.url))
def getDirectoryFileList(self, path):
"""Retrieve all entries in a given path with absolute paths as a list"""
return ["%s/%s"%(path, x) for x in self.getDirectoryContent(path)]
def removeFile(self, filepath):
"""Delete the file"""
try:
self.conn.unlink(filepath)
except error as msg:
raise SFTPError(str(msg) + 'while trying to delete %s on %s' % (filepath, self.url))
def renameFile(self, old_path, new_path):
"""Rename a file"""
try:
self.conn.rename(old_path, new_path)
except error as msg:
raise SFTPError('%s while trying to rename "%s" to "%s" on %s.' % \
(str(msg), old_path, new_path, self.url))
def createDirectory(self, path, mode=0o777):
"""Create a directory `path` with mode `mode`.
"""
return self.conn.mkdir(path, mode)
def removeDirectory(self, path):
"""Remove directory `path`.
"""
return self.conn.rmdir(path)
def logout(self):
"""Logout of the SFTP Server"""
self.conn.close()
self.transport.close()