commit e992f35ca6175ec53ec9966ca17966d86c129e8b Author: Arturo Filastò arturo@filasto.net Date: Thu Sep 1 18:34:48 2016 +0200

Improvements to start, stop, status workflow of ooniprobe-agent

* Better support for running it across different users --- ooni/scripts/ooniprobe_agent.py | 64 +++++++++++++++++++++++++++++------------ 1 file changed, 46 insertions(+), 18 deletions(-)

diff --git a/ooni/scripts/ooniprobe_agent.py b/ooni/scripts/ooniprobe_agent.py index ecfe7d8..f56f2df 100644 --- a/ooni/scripts/ooniprobe_agent.py +++ b/ooni/scripts/ooniprobe_agent.py @@ -2,6 +2,7 @@ from __future__ import print_function

import os import time +import errno import signal

from twisted.scripts import twistd @@ -55,7 +56,8 @@ def start_agent(options=None):

# Since we are starting the logger below ourselves we make twistd log to # a null log observer - twistd_args = ['--logger', 'ooni.utils.log.ooniloggerNull'] + twistd_args = ['--logger', 'ooni.utils.log.ooniloggerNull', + '--umask', '022'] twistd_config = OoniprobeTwistdConfig() if options is not None: twistd_args.extend(options.twistd_args) @@ -68,9 +70,12 @@ def start_agent(options=None): "StartOoniprobeAgent": StartOoniprobeAgentPlugin() }

- if status_agent() == 0: + try: + get_running_pidfile() print("Stop ooniprobe-agent before attempting to start it") return 1 + except NotRunning: + pass

print("Starting ooniprobe agent.") WEB_UI_URL = "http://%7B0%7D:%7B1%7D%22.format( @@ -80,8 +85,16 @@ def start_agent(options=None): twistd.runApp(twistd_config) return 0

-def status_agent(): - running = False + +class NotRunning(RuntimeError): + pass + +def get_running_pidfile(): + """ + :return: This pid of the running ooniprobe-agent instance. + :raises: NotRunning if it's not running + """ + running_pidfile = None for pidfile in [config.system_pid_path, config.user_pid_path]: if not os.path.exists(pidfile): # Didn't find the pid_file @@ -90,36 +103,51 @@ def status_agent(): pid = int(pid) try: os.kill(pid, signal.SIG_DFL) - running = True - except OSError, oserr: - if oserr.errno == 3: + running_pidfile = pidfile + break + except OSError as ose: + if ose.errno == errno.ESRCH: # Found pid, but isn't running continue - if running is True: + elif ose.errno == errno.EPERM: + # The process is owned by root. We assume it's running + running_pidfile = pidfile + break + if running_pidfile is None: + raise NotRunning + return running_pidfile + +def status_agent(): + try: + get_running_pidfile() print("ooniprobe-agent is running") return 0 - print("ooniprobe-agent is NOT running") - return 1 + except NotRunning: + print("ooniprobe-agent is NOT running") + return 1

def stop_agent(): # This function is borrowed from tahoe - pidfile = os.path.join( - config.running_path, - 'twistd.pid' - ) - if not os.path.exists(pidfile): - print("It seems like ooniprobe-agent is not running") + try: + pidfile = get_running_pidfile() + except NotRunning: + print("ooniprobe-agent is NOT running. Nothing to do.") return 2 + pid = open(pidfile, "r").read() pid = int(pid) try: os.kill(pid, signal.SIGKILL) - except OSError, oserr: - if oserr.errno == 3: + except OSError as ose: + if ose.errno == errno.ESRCH: print("No process was running. Cleaning up.") # the process didn't exist, so wipe the pid file os.remove(pidfile) return 2 + elif ose.errno == errno.EPERM: + # The process is owned by root. We assume it's running + print("ooniprobe-agent is owned by root. We cannot stop it.") + return 3 else: raise try: