How to Execute Multiple Commands in a Single Session in Paramiko - Python

How do you execute multiple commands in a single session in Paramiko? (Python)

Non-Interactive use cases

This is a non-interactive example... it sends cd tmp, ls and then exit.

import sys
sys.stderr = open('/dev/null')       # Silence silly warnings from paramiko
import paramiko as pm
sys.stderr = sys.__stderr__
import os

class AllowAllKeys(pm.MissingHostKeyPolicy):
    def missing_host_key(self, client, hostname, key):
        return

HOST = '127.0.0.1'
USER = ''
PASSWORD = ''

client = pm.SSHClient()
client.load_system_host_keys()
client.load_host_keys(os.path.expanduser('~/.ssh/known_hosts'))
client.set_missing_host_key_policy(AllowAllKeys())
client.connect(HOST, username=USER, password=PASSWORD)

channel = client.invoke_shell()
stdin = channel.makefile('wb')
stdout = channel.makefile('rb')

stdin.write('''
cd tmp
ls
exit
''')
print stdout.read()

stdout.close()
stdin.close()
client.close()

Interactive use cases

If you have an interactive ssh use case, paramiko can handle it but this answer won't help... I personally would use something based on exscript (which uses paramiko) or pexpect for interactive ssh sessions.

Execute two commands in a row using one SSH object via paramiko

It's not

ssh.exec_command('command1' ; 'command2')

Should be

ssh.exec_command('command1 ; command2')

Execute multiple dependent commands individually with Paramiko and find out when each command finishes

It seems that you want to implement an interactive shell, yet you need to control individual commands execution. That's not really possible with just SSH interface. "shell" channel in SSH is black box with an input and output. So there's nothing in Paramiko that will help you implementing this.

If you need to find out when a specific command finishes or where an output of a specific command ends, you need to use features of a shell.

You can solve that by inserting a unique separator (string) in between and search for it in the channel output stream. With a common *nix shells something like this works:

channel = ssh.invoke_shell()
channel.send('cd /mytargetRep\n')
channel.send('echo unique-string-separating-output-of-the-commands\n')
channel.send('./executeWhatIWant\n')

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Though I do not really think that you need that very often. Most commands that are needed to make a specific commands working, like cd or set, do not really output anything.

So in most cases you can use SSHClient.exec_command and your code will be a way simpler and more reliable:

Execute multiple commands in Paramiko so that commands are affected by their predecessors

Even if you need to use something seemingly complex like su/sudo, it is still better to stick with SSHClient.exec_command:

Executing command using "su -l" in SSH using Python

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For a similar question, see:

Combining interactive shell and recv_exit_status method using Paramiko

Python paramiko module using multiple commands

With just paramiko after the exec_command executes the channel is closed and the ssh returns an auth prompt.

Seems its not possible with just paramiko, try fabric or another tool.

** fabric did not work out too.

How do you execute multiple commands in a single session in Paramiko? (Python)

Non-Interactive use cases

This is a non-interactive example... it sends cd tmp, ls and then exit.

import sys
sys.stderr = open('/dev/null')       # Silence silly warnings from paramiko
import paramiko as pm
sys.stderr = sys.__stderr__
import os

class AllowAllKeys(pm.MissingHostKeyPolicy):
    def missing_host_key(self, client, hostname, key):
        return

HOST = '127.0.0.1'
USER = ''
PASSWORD = ''

client = pm.SSHClient()
client.load_system_host_keys()
client.load_host_keys(os.path.expanduser('~/.ssh/known_hosts'))
client.set_missing_host_key_policy(AllowAllKeys())
client.connect(HOST, username=USER, password=PASSWORD)

channel = client.invoke_shell()
stdin = channel.makefile('wb')
stdout = channel.makefile('rb')

stdin.write('''
cd tmp
ls
exit
''')
print stdout.read()

stdout.close()
stdin.close()
client.close()

Interactive use cases

If you have an interactive ssh use case, paramiko can handle it but this answer won't help... I personally would use something based on exscript (which uses paramiko) or pexpect for interactive ssh sessions.

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