https://github.com/NYUCCL/psiTurk
Tip revision: 8464eaf3857efc431f33bb15b380223e85ced495 authored by Dave Eargle on 25 January 2017, 03:29:56 UTC
bumping version
bumping version
Tip revision: 8464eaf
experiment_server_controller.py
import os
import sys
import subprocess
import signal
import webbrowser
from threading import Thread, Event
import urllib2
import socket
import psutil
import time
#!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# Supporting functions
# general purpose helper functions used by the dashboard server and controller
#!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
def is_port_available(ip, port):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(1)
try:
s.connect((ip, int(port)))
s.shutdown(2)
return False
except socket.timeout:
print "*** Failed to test port availability. Check that host\nis set properly in config.txt"
return True
except socket.error,e:
return True
def wait_until_online(function, ip, port):
"""
Uses Wait_For_State to wait for the server to come online, then runs the given function.
"""
awaiting_service = Wait_For_State(lambda: not is_port_available(ip, port), function)
awaiting_service.start()
return awaiting_service
def launch_browser(host, port, route):
launchurl = "http://{host}:{port}/{route}".format(host=host, port=port, route=route)
webbrowser.open(launchurl, new=1, autoraise=True)
def launch_browser_when_online(ip, port, route):
return wait_until_online(lambda: launch_browser(ip, port, route), ip, port)
#----------------------------------------------------------------
# handles waiting for processes which we don't control (e.g.,
# browser requests)
#----------------------------------------------------------------
class Wait_For_State(Thread):
"""
Waits for a state-checking function to return True, then runs a given
function. For example, this is used to launch the browser once the server is
started up.
Example:
t = Wait_For_State(lambda: server.check_port_state(), lambda: print "Server has started!")
t.start()
t.cancel() # Cancels thread
"""
def __init__(self, state_function, function, pollinterval=1):
Thread.__init__(self)
self.function = function
self.state_function = state_function
self.pollinterval = pollinterval
self.finished = Event()
self.final = lambda: ()
def cancel(self):
self.finished.set()
def run(self):
while not self.finished.is_set():
if self.state_function():
self.function()
self.finished.set()
else:
self.finished.wait(self.pollinterval)
#----------------------------------------------
# vanilla exception handler
#----------------------------------------------
class ExperimentServerControllerException(Exception):
def __init__(self, value):
self.value = value
def __str__(self):
return repr(self.value)
#----------------------------------------------
# simple wrapper class to control the
# starting/stopping of experiment server
#----------------------------------------------
class ExperimentServerController:
def __init__(self, config):
self.config = config
self.server_running = False
def get_ppid(self):
if not self.is_port_available():
url = "http://{hostname}:{port}/ppid".format(hostname=self.config.get("Server Parameters", "host"), port=self.config.getint("Server Parameters", "port"))
ppid_request = urllib2.Request(url)
ppid = urllib2.urlopen(ppid_request).read()
return ppid
else:
raise ExperimentServerControllerException("Cannot shut down experiment server, server not online")
def restart(self):
self.shutdown()
self.startup()
def shutdown(self, ppid=None):
if not ppid:
ppid = self.get_ppid()
print("Shutting down experiment server at pid %s..." % ppid)
try:
os.kill(int(ppid), signal.SIGKILL)
self.server_running = False
except ExperimentServerControllerException:
print ExperimentServerControllerException
else:
self.server_running = False
def kill_child_processes(self, parent_pid, sig=signal.SIGTERM):
if os.uname()[0] is 'Linux':
ps_command = subprocess.Popen('pstree -p %d | perl -ne \'print "$1 "\
while /\((\d+)\)/g\'' % parent.pid,
shell=True, stdout=subprocess.PIPE)
ps_output = ps_command.stdout.read()
retcode = ps_command.wait()
assert retcode == 0, "ps command returned %d" % retcode
for pid_str in ps_output.split("\n")[:-1]:
os.kill(int(pid_str), sig)
if os.uname()[0] is 'Darwin':
child_pid = parent.get_children(recursive=True)
for pid in child_pid:
pid.send_signal(signal.SIGTERM)
def is_server_running(self):
PROCNAME = "psiturk_experiment_server"
cmd = "ps -o pid,command | grep '"+ PROCNAME + "' | grep -v grep | awk '{print $1}'"
psiturk_exp_processes = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE)
output = psiturk_exp_processes.stdout.readlines()
parent = psutil.Process(psiturk_exp_processes.pid)
self.kill_child_processes(parent.pid)
if output:
is_psiturk_using_port = True
else:
is_psiturk_using_port = False
is_port_open = self.is_port_available()
#print self.server_running, " ", portopen
if is_port_open and is_psiturk_using_port: # This should never occur
return 'maybe'
elif not is_port_open and not is_psiturk_using_port:
return 'blocked'
elif is_port_open and not is_psiturk_using_port:
return 'no'
elif not is_port_open and is_psiturk_using_port:
return 'yes'
def is_port_available(self):
return is_port_available(self.config.get("Server Parameters", "host"), self.config.getint("Server Parameters", "port"))
def startup(self):
server_command = "{python_exec} '{server_script}'".format(
python_exec = sys.executable,
server_script = os.path.join(os.path.dirname(__file__), "experiment_server.py")
)
server_status = self.is_server_running()
if server_status == 'no':
#print "Running experiment server with command:", server_command
subprocess.Popen(server_command, shell=True, close_fds=True)
print "Experiment server launching..."
self.server_running = True
elif server_status == 'maybe':
print "Error: Not sure what to tell you..."
elif server_status == 'yes':
print "Experiment server may be already running..."
elif server_status == 'blocked':
print "Another process is running on the desired port. Try using a different port number."
time.sleep(1.2) # Allow CLI to catch up.