ollien ollien - 1 month ago 9
Python Question

Paramiko: read from standard output of remotely executed command

so I was working with paramiko for some basic SSH testing and I'm not getting any output into stdout. Heres my code.

import paramiko
client=paramiko.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
com="ls ~/desktop"
client.connect('MyIPAddress',MyPortNumber, username='username', password='password')
output=""
stdin, stdout, stderr = client.exec_command(com)

print "ssh succuessful. Closing connection"
client.close()
print "Connection closed"
stdout=stdout.readlines()
print stdout
print com
for line in stdout:
output=output+line
if output!="":
print output
else:
print "There was no output for this command"


So whenever I run this, the command is executed (as seen by if I do something like a cp, the file is copied), but I always get "There was no output for this command". When stdout=stdout.readlines() is printed, [] is the output. In addition, if I add a print statement into the for loop, it never gets run. Could someone help me out here? Thanks!

Answer

You have closed the connection before reading lines:

import paramiko
client=paramiko.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
com="ls ~/desktop"
client.connect('MyIPAddress',MyPortNumber, username='username', password='password')
output=""
stdin, stdout, stderr = client.exec_command(com)

print "ssh succuessful. Closing connection"
stdout=stdout.readlines()
client.close()
print "Connection closed"

print stdout
print com
for line in stdout:
    output=output+line
if output!="":
    print output
else:
    print "There was no output for this command"
Comments