#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
| This file is part of the web2py Web Framework
| Created by Attila Csipa <web2py@csipa.in.rs>
| Modified by Massimo Di Pierro <mdipierro@cs.depaul.edu>
| License: LGPLv3 (http://www.gnu.org/licenses/lgpl.html)
Cron-style interface
"""
import sys
import os
import threading
import logging
import time
import sched
import re
import datetime
import platform
import portalocker
import fileutils
try:
import cPickle as pickle
except:
import pickle
from gluon.settings import global_settings
logger = logging.getLogger("web2py.cron")
_cron_stopping = False
_cron_subprocs = []
[docs]def absolute_path_link(path):
"""
Returns an absolute path for the destination of a symlink
"""
if os.path.islink(path):
link = os.readlink(path)
if not os.path.isabs(link):
link = os.path.join(os.path.dirname(path), link)
else:
link = os.path.abspath(path)
return link
[docs]def stopcron():
"""Graceful shutdown of cron"""
global _cron_stopping
_cron_stopping = True
while _cron_subprocs:
proc = _cron_subprocs.pop()
if proc.poll() is None:
try:
proc.terminate()
except:
import traceback
traceback.print_exc()
[docs]class extcron(threading.Thread):
def __init__(self, applications_parent, apps=None):
threading.Thread.__init__(self)
self.setDaemon(False)
self.path = applications_parent
self.apps = apps
# crondance(self.path, 'external', startup=True, apps=self.apps)
[docs] def run(self):
if not _cron_stopping:
logger.debug('external cron invocation')
crondance(self.path, 'external', startup=False, apps=self.apps)
[docs]class hardcron(threading.Thread):
def __init__(self, applications_parent):
threading.Thread.__init__(self)
self.setDaemon(True)
self.path = applications_parent
crondance(self.path, 'hard', startup=True)
[docs] def launch(self):
if not _cron_stopping:
logger.debug('hard cron invocation')
crondance(self.path, 'hard', startup=False)
[docs] def run(self):
s = sched.scheduler(time.time, time.sleep)
logger.info('Hard cron daemon started')
while not _cron_stopping:
now = time.time()
s.enter(60 - now % 60, 1, self.launch, ())
s.run()
[docs]class softcron(threading.Thread):
def __init__(self, applications_parent):
threading.Thread.__init__(self)
self.path = applications_parent
# crondance(self.path, 'soft', startup=True)
[docs] def run(self):
if not _cron_stopping:
logger.debug('soft cron invocation')
crondance(self.path, 'soft', startup=False)
[docs]class Token(object):
def __init__(self, path):
self.path = os.path.join(path, 'cron.master')
if not os.path.exists(self.path):
fileutils.write_file(self.path, '', 'wb')
self.master = None
self.now = time.time()
[docs] def acquire(self, startup=False):
"""
Returns the time when the lock is acquired or
None if cron already running
lock is implemented by writing a pickle (start, stop) in cron.master
start is time when cron job starts and stop is time when cron completed
stop == 0 if job started but did not yet complete
if a cron job started within less than 60 seconds, acquire returns None
if a cron job started before 60 seconds and did not stop,
a warning is issue "Stale cron.master detected"
"""
if sys.platform == 'win32':
locktime = 59.5
else:
locktime = 59.99
if portalocker.LOCK_EX is None:
logger.warning('WEB2PY CRON: Disabled because no file locking')
return None
self.master = open(self.path, 'rb+')
try:
ret = None
portalocker.lock(self.master, portalocker.LOCK_EX)
try:
(start, stop) = pickle.load(self.master)
except:
(start, stop) = (0, 1)
if startup or self.now - start > locktime:
ret = self.now
if not stop:
# this happens if previous cron job longer than 1 minute
logger.warning('WEB2PY CRON: Stale cron.master detected')
logger.debug('WEB2PY CRON: Acquiring lock')
self.master.seek(0)
pickle.dump((self.now, 0), self.master)
self.master.flush()
finally:
portalocker.unlock(self.master)
if not ret:
# do this so no need to release
self.master.close()
return ret
[docs] def release(self):
"""
Writes into cron.master the time when cron job was completed
"""
if not self.master.closed:
portalocker.lock(self.master, portalocker.LOCK_EX)
logger.debug('WEB2PY CRON: Releasing cron lock')
self.master.seek(0)
(start, stop) = pickle.load(self.master)
if start == self.now: # if this is my lock
self.master.seek(0)
pickle.dump((self.now, time.time()), self.master)
portalocker.unlock(self.master)
self.master.close()
[docs]def rangetolist(s, period='min'):
retval = []
if s.startswith('*'):
if period == 'min':
s = s.replace('*', '0-59', 1)
elif period == 'hr':
s = s.replace('*', '0-23', 1)
elif period == 'dom':
s = s.replace('*', '1-31', 1)
elif period == 'mon':
s = s.replace('*', '1-12', 1)
elif period == 'dow':
s = s.replace('*', '0-6', 1)
m = re.compile(r'(\d+)-(\d+)/(\d+)')
match = m.match(s)
if match:
for i in range(int(match.group(1)), int(match.group(2)) + 1):
if i % int(match.group(3)) == 0:
retval.append(i)
return retval
[docs]def parsecronline(line):
task = {}
if line.startswith('@reboot'):
line = line.replace('@reboot', '-1 * * * *')
elif line.startswith('@yearly'):
line = line.replace('@yearly', '0 0 1 1 *')
elif line.startswith('@annually'):
line = line.replace('@annually', '0 0 1 1 *')
elif line.startswith('@monthly'):
line = line.replace('@monthly', '0 0 1 * *')
elif line.startswith('@weekly'):
line = line.replace('@weekly', '0 0 * * 0')
elif line.startswith('@daily'):
line = line.replace('@daily', '0 0 * * *')
elif line.startswith('@midnight'):
line = line.replace('@midnight', '0 0 * * *')
elif line.startswith('@hourly'):
line = line.replace('@hourly', '0 * * * *')
params = line.strip().split(None, 6)
if len(params) < 7:
return None
daysofweek = {'sun': 0, 'mon': 1, 'tue': 2, 'wed': 3, 'thu': 4,
'fri': 5, 'sat': 6}
for (s, id) in zip(params[:5], ['min', 'hr', 'dom', 'mon', 'dow']):
if not s in [None, '*']:
task[id] = []
vals = s.split(',')
for val in vals:
if val != '-1' and '-' in val and '/' not in val:
val = '%s/1' % val
if '/' in val:
task[id] += rangetolist(val, id)
elif val.isdigit() or val == '-1':
task[id].append(int(val))
elif id == 'dow' and val[:3].lower() in daysofweek:
task[id].append(daysofweek(val[:3].lower()))
task['user'] = params[5]
task['cmd'] = params[6]
return task
[docs]class cronlauncher(threading.Thread):
def __init__(self, cmd, shell=True):
threading.Thread.__init__(self)
if platform.system() == 'Windows':
shell = False
self.cmd = cmd
self.shell = shell
[docs] def run(self):
import subprocess
global _cron_subprocs
if isinstance(self.cmd, (list, tuple)):
cmd = self.cmd
else:
cmd = self.cmd.split()
proc = subprocess.Popen(cmd,
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
shell=self.shell)
_cron_subprocs.append(proc)
(stdoutdata, stderrdata) = proc.communicate()
try:
_cron_subprocs.remove(proc)
except ValueError:
pass
if proc.returncode != 0:
logger.warning(
'WEB2PY CRON Call returned code %s:\n%s' %
(proc.returncode, stdoutdata + stderrdata))
else:
logger.debug('WEB2PY CRON Call returned success:\n%s'
% stdoutdata)
[docs]def crondance(applications_parent, ctype='soft', startup=False, apps=None):
apppath = os.path.join(applications_parent, 'applications')
cron_path = os.path.join(applications_parent)
token = Token(cron_path)
cronmaster = token.acquire(startup=startup)
if not cronmaster:
return
now_s = time.localtime()
checks = (('min', now_s.tm_min),
('hr', now_s.tm_hour),
('mon', now_s.tm_mon),
('dom', now_s.tm_mday),
('dow', (now_s.tm_wday + 1) % 7))
if apps is None:
apps = [x for x in os.listdir(apppath)
if os.path.isdir(os.path.join(apppath, x))]
full_apath_links = set()
for app in apps:
if _cron_stopping:
break
apath = os.path.join(apppath, app)
# if app is a symbolic link to other app, skip it
full_apath_link = absolute_path_link(apath)
if full_apath_link in full_apath_links:
continue
else:
full_apath_links.add(full_apath_link)
cronpath = os.path.join(apath, 'cron')
crontab = os.path.join(cronpath, 'crontab')
if not os.path.exists(crontab):
continue
try:
cronlines = fileutils.readlines_file(crontab, 'rt')
lines = [x.strip() for x in cronlines if x.strip(
) and not x.strip().startswith('#')]
tasks = [parsecronline(cline) for cline in lines]
except Exception, e:
logger.error('WEB2PY CRON: crontab read error %s' % e)
continue
for task in tasks:
if _cron_stopping:
break
if sys.executable.lower().endswith('pythonservice.exe'):
_python_exe = os.path.join(sys.exec_prefix, 'python.exe')
else:
_python_exe = sys.executable
commands = [_python_exe]
w2p_path = fileutils.abspath('web2py.py', gluon=True)
if os.path.exists(w2p_path):
commands.append(w2p_path)
if applications_parent != global_settings.gluon_parent:
commands.extend(('-f', applications_parent))
citems = [(k in task and not v in task[k]) for k, v in checks]
task_min = task.get('min', [])
if not task:
continue
elif not startup and task_min == [-1]:
continue
elif task_min != [-1] and reduce(lambda a, b: a or b, citems):
continue
logger.info('WEB2PY CRON (%s): %s executing %s in %s at %s'
% (ctype, app, task.get('cmd'),
os.getcwd(), datetime.datetime.now()))
action, command, models = False, task['cmd'], ''
if command.startswith('**'):
(action, models, command) = (True, '', command[2:])
elif command.startswith('*'):
(action, models, command) = (True, '-M', command[1:])
else:
action = False
if action and command.endswith('.py'):
commands.extend(('-J', # cron job
models, # import models?
'-S', app, # app name
'-a', '"<recycle>"', # password
'-R', command)) # command
elif action:
commands.extend(('-J', # cron job
models, # import models?
'-S', app + '/' + command, # app name
'-a', '"<recycle>"')) # password
else:
commands = command
# from python docs:
# You do not need shell=True to run a batch file or
# console-based executable.
shell = False
try:
cronlauncher(commands, shell=shell).start()
except Exception, e:
logger.warning(
'WEB2PY CRON: Execution error for %s: %s'
% (task.get('cmd'), e))
token.release()