I would like to write a script that performs the following Linux commands sequence:
I was naively (and stupidly) tried to accomplish that with a simple os.system bear in mind I using python 2.3 and would like to avoid adding modules (if possible).
Thanks in advance!
[EDIT] Check out also another example using paramiko on http://code.google.com/p/lexel-intern0t/source/browse/trunk/Python/ssh_client.py.
The script found on http://media.commandline.org.uk//code/ssh.txt may help you. It includes os module (to find the keys) and tempfile module for logging purposes, both found in python 2.3 global module index ( http://docs.python.org/release/2.3/modindex.html ) and paramiko ( http://www.lag.net/paramiko/docs/ ) for the SSH2 protocol implementation, which is supposed to work on python 2.3 and above. It's a simple piece of code:
"""Friendly Python SSH2 interface."""
import os
import tempfile
import paramiko
class Connection(object):
"""Connects and logs into the specified hostname.
Arguments that are not given are guessed from the environment."""
def __init__(self,
host,
username = None,
private_key = None,
password = None,
port = 22,
):
self._sftp_live = False
self._sftp = None
if not username:
username = os.environ['LOGNAME']
# Log to a temporary file.
templog = tempfile.mkstemp('.txt', 'ssh-')[1]
paramiko.util.log_to_file(templog)
# Begin the SSH transport.
self._transport = paramiko.Transport((host, port))
self._tranport_live = True
# Authenticate the transport.
if password:
# Using Password.
self._transport.connect(username = username, password = password)
else:
# Use Private Key.
if not private_key:
# Try to use default key.
if os.path.exists(os.path.expanduser('~/.ssh/id_rsa')):
private_key = '~/.ssh/id_rsa'
elif os.path.exists(os.path.expanduser('~/.ssh/id_dsa')):
private_key = '~/.ssh/id_dsa'
else:
raise TypeError, "You have not specified a password or key."
private_key_file = os.path.expanduser(private_key)
rsa_key = paramiko.RSAKey.from_private_key_file(private_key_file)
self._transport.connect(username = username, pkey = rsa_key)
def _sftp_connect(self):
"""Establish the SFTP connection."""
if not self._sftp_live:
self._sftp = paramiko.SFTPClient.from_transport(self._transport)
self._sftp_live = True
def get(self, remotepath, localpath = None):
"""Copies a file between the remote host and the local host."""
if not localpath:
localpath = os.path.split(remotepath)[1]
self._sftp_connect()
self._sftp.get(remotepath, localpath)
def put(self, localpath, remotepath = None):
"""Copies a file between the local host and the remote host."""
if not remotepath:
remotepath = os.path.split(localpath)[1]
self._sftp_connect()
self._sftp.put(localpath, remotepath)
def execute(self, command):
"""Execute the given commands on a remote machine."""
channel = self._transport.open_session()
channel.exec_command(command)
output = channel.makefile('rb', -1).readlines()
if output:
return output
else:
return channel.makefile_stderr('rb', -1).readlines()
def close(self):
"""Closes the connection and cleans up."""
# Close SFTP Connection.
if self._sftp_live:
self._sftp.close()
self._sftp_live = False
# Close the SSH Transport.
if self._tranport_live:
self._transport.close()
self._tranport_live = False
def __del__(self):
"""Attempt to clean up if not explicitly closed."""
self.close()
def main():
"""Little test when called directly."""
# Set these to your own details.
myssh = Connection('example.com')
myssh.put('ssh.py')
myssh.close()
# start the ball rolling.
if __name__ == "__main__":
main()
