Running a command on a remote server to find the uptime in seconds

Question

Here's what I have so far:

#!/usr/bin/python

import sys
import os
import subprocess
from subprocess import check_output
import time
import sh
from sh import sshpass
import re
import time, datetime
check_time = 0

with open("log.txt", "a") as f:
    while 1:
        #out = check_output(["sshpass", "-p", "pass", "ssh",
        #                    "theo@localhost", "\"/usr/bin/cat",
        #                    "/proc/uptime\""])
        #print (out)
        #out = str(out)
        uptime = sh.Command("/usr/bin/sshpass")
        result = uptime("-p", "pass", "ssh", "theo@localhost", "\"cat",
                        "/proc/uptime\"")
        result = str(result)
        print (result)
        result = result.split(' ', 1)[0]
        print (result)
        f.write(result)
        result_int = int(result)
        if result_int > check_time:
            print("it rebooted", result_int, "minutes ago")

        time.sleep(5)

Results:

checking uptime
Traceback (most recent call last):
  File "./uptime.py", line 23, in <module>
    result = uptime("-p", "pass", "ssh", "theo@localhost", "\"cat", "/proc/uptime\"")
  File "/usr/lib/python3.5/site-packages/sh.py", line 1021, in __call__
    return RunningCommand(cmd, call_args, stdin, stdout, stderr)
  File "/usr/lib/python3.5/site-packages/sh.py", line 486, in __init__
    self.wait()
  File "/usr/lib/python3.5/site-packages/sh.py", line 500, in wait
    self.handle_command_exit_code(exit_code)
  File "/usr/lib/python3.5/site-packages/sh.py", line 516, in handle_command_exit_code
    raise exc(self.ran, self.process.stdout, self.process.stderr)
sh.ErrorReturnCode_127:

  RAN: '/usr/bin/sshpass -p pass ssh theo@localhost "cat /proc/uptime"'

  STDOUT:


  STDERR:
zsh:1: no such file or directory: cat /proc/uptime

You can see I have two attempts, one using the sh library and one with check_output, both result in the same error about not being able to run /usr/bin/cat /proc/uptime .

However as you can see at the end of the traceback:

RAN: '/usr/bin/sshpass -p pass ssh theo@localhost "cat /proc/uptime"'

That appears to be a perfectly valid line, and if I copy paste it into a terminal it works.

Any ideas? The command does actually work if I just put in "uptime", but rather than editing the output of that to get the time in seconds, I though it would be easier to do it this way (at least I thought it would be) :)

I'm using python 3.5.2

Answer 1

Based on the output, you need to modify your uptime line to look something like this:

        result = uptime("-p", "pass", "ssh", "theo@localhost", "cat",
                    "/proc/uptime")

It looks like "cat /proc/uptime" is interpreted as one argument by ssh in your original code.

Answer 2

Someone on IRC suggested I use command_string = "cat /proc/cpu/" and

result = uptime("-p", "pass", "ssh", "theo@localhost", command_string)

Which works!