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How to execute awk command inside python

I am trying to run the following awk command inside python but I get a syntax error related to the quotes:
import subprocess
COMMAND = "df /dev/sda1 | awk /'NR==2 {sub("%","",$5); if ($5 >= 80) {printf "Warning! Space usage is %d%%", $5}}"
subprocess.call(COMMAND, shell=True)
I tried to escape the quotes but I am still getting the same error.

You may want to put ''' or """ around the string since you have both ' and ".
import subprocess
COMMAND = '''"df /dev/sda1 | awk /'NR==2 {sub("%","",$5); if ($5 >= 80) {printf "Warning! Space usage is %d%%", $5}}"'''
subprocess.call(COMMAND, shell=True)
There also seems to be a relevant answer already for this as well: awk commands within python script

Try this:
import subprocess
COMMAND="df /dev/sda1 | awk 'NR==2 {sub(\"%\",\"\",$5); if ($5 >= 80) {printf \"Warning! Space usage is %d%%\", $5}}'"
subprocess.Popen(COMMAND,stdin=subprocess.PIPE,stdout=subprocess.PIPE, shell=True).stdout.read()

I was writing a python script for my deployment purpose and one part of the script was to explicitely kill the process if its not stopped successfully.
Below is the python code which actually performs
Find the processId of the process named myApplication
ps -ef | grep myApplication | grep -v grep | awk {'print $2'}
and then perform
kill -9 PID //where PID is output of earlier command
import subprocess
import signal
def killApplicationProcessIfStillRunning(app_name):
p1 = subprocess.Popen(['ps', '-ef'], stdout=subprocess.PIPE)
p2 = subprocess.Popen(['grep', app_name],stdin=p1.stdout, stdout=subprocess.PIPE)
p3 = subprocess.Popen(['grep', '-v' , 'grep'],stdin=p2.stdout, stdout=subprocess.PIPE)
p4 = subprocess.Popen(['awk', '{print $2}'],stdin=p3.stdout, stdout=subprocess.PIPE)
out, err = p4.communicate()
if out:
print 'Attempting to kill '+app_name +' process with PID ' +out.splitlines()[0]
os.kill(int(out.splitlines()[0]),signal.SIGKILL)
Now invoke the above method as
killApplicationProcessIfStillRunning(myApplication)
Hope it helps someone.

How to execute python subprocess.Popen with many Arguments?

I need to execute the same command on a local and remote server. So I'm using subprocess.Popen to execute, and local command work as expected, but when I execute on remote it gives me some error like command not found. I appreciate your support as I am new to this.
Local execution function
def topic_Offset_lz(self):
CMD = "/dsapps/admin/edp/scripts/edp-admin.sh kafka-topic offset %s -e %s | grep -v Getting |grep -v Verifying | egrep -v '^[[:space:]]*$|^#' | awk -F\: '{print $3}'|sed '%sq;d'" % (self.topic,self.envr,self.partition)
t_out_lz, t_error_lz = subprocess.Popen(CMD, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True).communicate()
return t_out_lz
Remote server execution
def topic_offset_sl(self):
CMD = "/dsapps/admin/edp/scripts/edp-admin.sh kafka-topic offset %s -e %s | grep -v Getting |grep -v Verifying | egrep -v '^[[:space:]]*$|^#' | awk -F\: '{print $3}'|sed '%sq;d'" % (self.topic, self.envr, self.partition)
t_out_sl, t_error_sl = subprocess.Popen(["ssh", "-q", CMD], stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True).communicate()
return t_error_sl
Error I'm getting for the remote execution
Landing Zone Offset: 0
SoftLayer Zone Offset: /bin/sh: ^# |sed 1: command not found
/bin/sh: d: command not found

I came up with below solution, might be there will easy way rather than this.
def topic_offset_sl(self):
CMD_SL1 = "ssh -q %s '/dsapps/admin/edp/scripts/edp-admin.sh kafka-topic offset %s -e %s'" % (KEY_SERVER,self.topic, self.envr)
CMD_SL2 = "| grep -v Getting |grep -v Verifying | egrep -v '^[[:space:]]*$|^#' | awk -F\: '{print $3}'|sed '%sq;d'" % (self.partition)
t_out_sl, t_error_sl = subprocess.Popen(CMD_SL1 + CMD_SL2 , stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True).communicate()
return t_out_sl

The ssh command passes its argument vector as a single command line string, not an array. To do this, it simply concatenates the arguments, without performing shell quoting:
$ ssh target "python -c 'import sys;print(sys.argv)'" 1 2 3
['-c', '1', '2', '3']
$ ssh target "python -c 'import sys;print(sys.argv)'" "1 2 3"
['-c', '1', '2', '3']
If there was proper shell quoting, the distinction between 1 2 3 and "1 2 3" would have been preserved, and the first argument would not need double-quoting.
Anyway, in your case, the following might work:
def topic_offset_sl(self):
CMD = "ssh -q " + pipes.quote("/dsapps/admin/edp/scripts/edp-admin.sh"
+ " kafka-topic offset %s -e %s" % (self.topic, self.envr)) \
+ "grep -v Getting |grep -v Verifying | egrep -v '^[[:space:]]*$|^#'"
+ " | awk -F\: '{print $3}'|sed '%sq;d'" % self.partition
t_out_sl, t_error_sl = subprocess.Popen(CMD], stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True).communicate()
return t_error_sl
This assumes you only want to run the /dsapps/admin/edp/scripts/edp-admin.sh script remotely and not the rest.
Note that the way you use string splicing to construct command lines likely introduces shell command injection vulnerabilities (both locally and on the remote server).

Execute a bash command with parameter in Python

This is a bash command that I run in python and get the expected result:
count = subprocess.Popen("ps -ef | grep app | wc -l", stdout=subprocess.PIPE, shell=True)
but when I'd like to pass an argument (count in this case) cannot figure out how to do it.
I tried:
pid = subprocess.call("ps -ef | grep app | awk -v n=' + str(count), 'NR==n | awk \'{print $2}\'", shell=True)
and
args = shlex.split('ps -ef | grep app | awk -v n=' + str(count), 'NR==n | awk \'{print $2}\'')
pid = subprocess.Popen(args, stdout=subprocess.PIPE, shell=True)
among other attempts, from various posts here, but still cannot make it.

You're mixing opening and closing quotations and you pass a colon by mistake on your other attempts among other things.
Try this for a fix:
pid = subprocess.call("ps -ef | grep app | awk -v n=" + str(count) + " NR==n | awk '{print $2}'", shell=True)
You opened the command parameter with " and there for you need to close it before you do + str() with a " and not a '. Further more i swapped the , 'NR= with + "NR= since you want to append more to your command and not pass a argument to subprocess.call().
As pointed out in the comments, there's no point in splitting the command with shlex since piping commands isn't implemented in subprocess, I would however like to point out that using shell=True is usually not recommended because for instance one of the examples given here.

An other vay is using format:
pid = subprocess.call("ps -ef | grep app | awk -v n={} NR==n | awk '{{print $2}}'".format(str(count)), shell=True)

Your Awk pipeline could be simplified a great deal - if the goal is to print the last match, ps -ef | awk '/app/ { p=$2 } END { print p }' does that. But many times, running Awk from Python is just silly, and performing the filtering in Python is convenient and easy, as well as obviously more efficient (you save not only the Awk process, but also the pesky shell=True).
for p in subprocess.check_output(['ps', '-ef']).split('\n'):
if 'app' in p:
pid = p.split()[1]

Handle result of os.system

I'm using python to script a functional script and I can't handler the result of this command line:
os.system("ps aux -u %s | grep %s | grep -v 'grep' | awk '{print $2}'" % (username, process_name)
It shows me pids but I can't use it as List.
If I test:
pids = os.system("ps aux -u %s | grep %s | grep -v 'grep' | awk '{print $2}'" % (username, process_name)
print type(pids)
#Results
29719
30205
31037
31612
<type 'int'>
Why is pids an int? How can I handle this result as List?
Stranger part:
print type(os.system("ps aux -u %s | grep %s | grep -v 'grep' | awk '{print $2}'" % (username, process_name))
There is nothing. Not any type written on my console..

os.system does not capture the output of the command it runs. To do so you need to use subprocess.
from subprocess import check_output
out = check_output("your command goes here", shell=true)
The above will work in Python 2.7. For older Pythons, use:
import subprocess
p = subprocess.Popen("your command goes here", stdout=subprocess.PIPE, shell=True)
out, err = p.communicate()

os module documentation
os.system(command)
Execute the command (a string) in a subshell. This is implemented by calling the Standard C function system(), and has the same limitations. Changes to sys.stdin, etc. are not reflected in the environment of the executed command.
On Unix, the return value is the exit status of the process encoded in the format specified for wait(). Note that POSIX does not specify the meaning of the return value of the C system() function, so the return value of the Python function is system-dependent.
If you want access to the output of the command, use the subprocess module instead, e.g. check_output:
subprocess.check_output(args, *, stdin=None, stderr=None, shell=False, universal_newlines=False)
Run command with arguments and return its output as a byte string.

How to split up the command here for using subprocess.Popen()

ip = subprocess.Popen(["/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') | grep \"inet addr\" | awk -F: '{print $2}' | awk \'{print $1}\'"], stdout=subprocess.PIPE)
I am not sure where to put the commas to separate them to use this command using subprocess.Popen. Does anyone know?

You are using shell features (the pipe) so instead of splitting the command, you should pass it as a single string (not a list) with shell=True
ip = subprocess.Popen("/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') | grep \"inet addr\" | awk -F: '{print $2}' | awk \'{print $1}\'",
shell=True,
stdout=subprocess.PIPE)

Here's what I would recommend.
Create a file with this contents - call it 'route-info' and make it executable:
#!/bin/sh
/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') |
grep "inet addr" |
awk -F: '{print $2}' |
awk '{print $1}'
In your python program, use:
ip = subprocess.Popen(["/path/to/route-info"], stdout=subprocess.PIPE)
Then you don't have to worry about quoting characters and you can independently test the route-info script to make sure it is working correctly.
The script route-info doesn't take any command line arguments, but if it did this is how you would pass them:
ip = subprocess.Popen(["/path/to/route-info", arg1, arg2, ...], stdout=subprocess.PIPE)

Quoting the official documentation of subprocess.Popen here
It may not be obvious how to break a shell command into a sequence of
arguments, especially in complex cases. shlex.split() can illustrate
how to determine the correct tokenization for args:
import shlex, subprocess
command_line = input()
args = shlex.split(command_line)
print(args)
p = subprocess.Popen(args) # Success!
shlex is included in standard library so you need not to install it.
Writing it in a single line like str.split() should look like:
import shlex
import subprocess
command = "ls -l"
proc = subprocess.Popen(shlex.split(command) , stdout = subprocess.PIPE , stderr = subprocess.PIPE)
output , errors = proc.communicate()
print(output , errors)