093b8c14d6
Separate output by line, and execute the output callback once per line. Signed-off-by: Eric Callahan <arksine.code@gmail.com>
112 lines
3.3 KiB
Python
112 lines
3.3 KiB
Python
# linux shell command execution utility
|
|
#
|
|
# Copyright (C) 2020 Eric Callahan <arksine.code@gmail.com>
|
|
#
|
|
# This file may be distributed under the terms of the GNU GPLv3 license.
|
|
import os
|
|
import shlex
|
|
import subprocess
|
|
import logging
|
|
import tornado
|
|
from tornado import gen
|
|
from tornado.ioloop import IOLoop
|
|
|
|
class ShellCommand:
|
|
def __init__(self, cmd, callback):
|
|
self.io_loop = IOLoop.current()
|
|
self.name = cmd
|
|
self.output_cb = callback
|
|
cmd = os.path.expanduser(cmd)
|
|
self.command = shlex.split(cmd)
|
|
self.partial_output = b""
|
|
self.cancelled = False
|
|
|
|
def _process_output(self, fd, events):
|
|
if events & IOLoop.ERROR:
|
|
return
|
|
try:
|
|
data = os.read(fd, 4096)
|
|
except Exception:
|
|
return
|
|
data = self.partial_output + data
|
|
lines = data.split(b'\n')
|
|
self.partial_output = lines.pop()
|
|
for line in lines:
|
|
try:
|
|
self.output_cb(line)
|
|
except Exception:
|
|
logging.exception("Error writing command output")
|
|
|
|
def cancel(self):
|
|
self.cancelled = True
|
|
|
|
async def run(self, timeout=2., verbose=True):
|
|
fd = None
|
|
if timeout is None:
|
|
# Never timeout
|
|
timeout = 9999999999999999.
|
|
if not timeout or self.output_cb is None:
|
|
# Fire and forget commands cannot be verbose as we can't
|
|
# clean up after the process terminates
|
|
verbose = False
|
|
try:
|
|
proc = subprocess.Popen(
|
|
self.command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
|
|
except Exception:
|
|
logging.exception(
|
|
f"shell_command: Command ({self.name}) failed")
|
|
return
|
|
if verbose:
|
|
fd = proc.stdout.fileno()
|
|
self.io_loop.add_handler(
|
|
fd, self._process_output, IOLoop.READ | IOLoop.ERROR)
|
|
elif not timeout:
|
|
# fire and forget, return from execution
|
|
return True
|
|
sleeptime = 0
|
|
complete = False
|
|
while sleeptime < timeout:
|
|
await gen.sleep(.05)
|
|
sleeptime += .05
|
|
if proc.poll() is not None:
|
|
complete = True
|
|
break
|
|
if self.cancelled:
|
|
break
|
|
if not complete:
|
|
proc.terminate()
|
|
if verbose:
|
|
if self.partial_output:
|
|
self.output_cb(self.partial_output)
|
|
self.partial_output = b""
|
|
if complete:
|
|
msg = f"Command ({self.name}) finished"
|
|
elif self.cancelled:
|
|
msg = f"Command ({self.name}) cancelled"
|
|
else:
|
|
msg = f"Command ({self.name}) timed out"
|
|
logging.info(msg)
|
|
self.io_loop.remove_handler(fd)
|
|
return complete
|
|
|
|
async def run_with_response(self, timeout=2.):
|
|
result = []
|
|
|
|
def cb(data):
|
|
data = data.strip()
|
|
if data:
|
|
result.append(data.decode())
|
|
prev_cb = self.output_cb
|
|
self.output_cb = cb
|
|
await self.run(timeout)
|
|
self.output_cb = prev_cb
|
|
return "\n".join(result)
|
|
|
|
|
|
class ShellCommandFactory:
|
|
def build_shell_command(self, cmd, callback=None):
|
|
return ShellCommand(cmd, callback)
|
|
|
|
def load_plugin(config):
|
|
return ShellCommandFactory()
|