import os
import errno
+import signal
import subprocess
+import logging ; log = logging.getLogger('pymin.procman')
+
+__all__ = ('ProcessManager', 'manager', 'register', 'unregister', 'once',
+ 'start', 'stop', 'restart', 'kill', 'get', 'has', 'sigchild_handler')
class ProcessInfo:
- def __init__(self, name, process, args, kw, callback=None, persist=False):
- self.name = name
- self.process = process
- self.args = args
- self.kw = kw
+ def __init__(self, name, command, callback=None, persist=False,
+ max_errors=3, args=None, kwargs=None):
+ self._name = name
+ self.command = command
self.callback = callback
+ if args is None: args = list()
+ self.args = args
+ if kwargs is None: kwargs = dict()
+ self.kwargs = kwargs
self.persist = persist
+ self.max_errors = max_errors
+ self.clear()
+ def clear(self):
+ self._dont_run = False
+ self._signal = None
+ self._process = None
+ self._error_count = 0
+ def start(self):
+ assert self.process is None
+ self.restart()
+ def restart(self):
+ self.clear()
+ log.debug(u'ProcessInfo.restart(): executing %s', self.command)
+ self._process = subprocess.Popen(self.command,
+ *self.args, **self.kwargs)
+ def stop(self):
+ assert self.process is not None
+ self._dont_run = True
+ if self._signal == signal.SIGTERM or self._signal == signal.SIGKILL:
+ # Allready stopped, kill it
+ self.kill(signal.SIGKILL)
+ else:
+ # Stop it
+ self.kill(signal.SIGTERM)
+ def kill(self, signum):
+ log.debug(u'ProcessInfo.kill(): killing pid %s with signal %s',
+ self.process.pid, signum)
+ assert self.process is not None
+ os.kill(self.process.pid, signum)
+ self._signal = signum
+ @property
+ def running(self):
+ return self.process is not None and self.process.poll() is None
+ @property
+ def name(self):
+ return self._name
+ @property
+ def process(self):
+ return self._process
+ @property
+ def error_count(self):
+ return self._error_count
def __repr__(self):
- return 'ProcessInfo(name=%s, pid=%s, persist=%s, cb=%s, args=%s)' % (
- self.name, self.process.pid, self.persist,
- self.callback.__name__, self.args)
+ pid = None
+ if self.process is not None:
+ pid = self.process.pid
+ return 'ProcessInfo(name=%s, pid=%s command=%s, persist=%s, cb=%s)' % (
+ self.name, pid, self.command, self.persist,
+ self.callback and self.callback.__name__ or None)
class ProcessManager:
def __init__(self):
+ self.services = dict()
self.namemap = dict()
self.pidmap = dict()
+ log.debug(u'ProcessManager()')
- def call(self, name, callback, persist, *args, **kw):
- proc = subprocess.Popen(*args, **kw)
- procinfo = ProcessInfo(name, proc, args, kw, callback, persist)
- self.namemap[name] = self.pidmap[proc.pid] = procinfo
+ def register(self, name, command=None, callback=None, persist=False,
+ max_errors=3, *args, **kwargs):
+ log.debug(u'ProcessManager.register(%s, %s, %s, %s, %s, %s, %s)',
+ name, command, callback, persist, max_errors, args, kwargs)
+ if not isinstance(name, ProcessInfo):
+ pi = ProcessInfo(name, command, callback, persist, max_errors,
+ args, kwargs)
+ else:
+ pi = name
+ name = pi.name
+ assert not self.has(name)
+ self.services[name] = pi
+ return pi
+
+ def unregister(self, name):
+ log.debug(u'ProcessManager.unregister(%s)', name)
+ if isinstance(name, ProcessInfo):
+ pi = name
+ name = pi.name
+ else:
+ pi = self.services[name]
+ del self.services[name]
+ return pi
- def sigchild_handler(self, signum):
+ def _call(self, pi):
+ pi.start()
+ self.namemap[pi.name] = self.pidmap[pi.process.pid] = pi
+
+ def once(self, name, command=None, callback=None, persist=False,
+ max_errors=3, *args, **kwargs):
+ log.debug(u'ProcessManager.once(%s, %s, %s, %s, %s, %s, %s)',
+ name, command, callback, persist, max_errors, args, kwargs)
+ if not isinstance(name, ProcessInfo):
+ pi = ProcessInfo(name, command, callback, persist, max_errors,
+ args, kwargs)
+ else:
+ pi = name
+ name = pi.name
+ assert not self.has(name)
+ self._call(pi)
+ return pi
+
+ def start(self, name):
+ log.debug(u'ProcessManager.start(%s)', name)
+ if isinstance(name, ProcessInfo):
+ name = name.name
+ if name not in self.namemap:
+ self._call(self.services[name])
+ return True
+ return False
+
+ def stop(self, name):
+ log.debug(u'ProcessManager.stop(%s)', name)
+ if isinstance(name, ProcessInfo):
+ name = name.name
+ if name in self.namemap:
+ self.namemap[name].stop()
+ return True
+ return False
+
+ def restart(self, name):
+ log.debug(u'ProcessManager.restart(%s)', name)
+ if isinstance(name, ProcessInfo):
+ name = name.name
+ # we have to check first in namemap in case is an unregistered
+ # process (added with once())
+ if name in self.namemap:
+ pi = self.namemap[name]
+ # the process will change its PID, so we delete it while we know it
+ del self.pidmap[pi.process.pid]
+ pi.stop()
+ pi.process.wait()
+ pi.restart()
+ # add the new PID
+ self.pidmap[pi.process.pid] = pi
+ return True
+ else:
+ self.start(name)
+ return False
+
+ def kill(self, name, signum):
+ log.debug(u'ProcessManager.kill(%s, %s)', name, signum)
+ if isinstance(name, ProcessInfo):
+ name = name.name
+ if name in self.namemap:
+ self.namemap[name].kill(name, stop)
+ return True
+ return False
+
+ def sigchild_handler(self, signum, stack_frame=None):
+ log.debug(u'ProcessManager.sigchild_handler(%s)', signum)
try:
(pid, status) = os.waitpid(-1, os.WNOHANG)
except OSError, e:
- if e.errno is e.ECHILD:
+ log.debug(u'ProcessManager.sigchild_handler(): OSError')
+ if e.errno is errno.ECHILD:
+ log.debug(u'ProcessManager.sigchild_handler(): OSError ECHILD')
return
raise
+ log.debug(u'ProcessManager.sigchild_handler: pid=%s, status=%s',
+ pid, status)
while pid:
if pid in self.pidmap:
p = self.pidmap[pid]
- del self.namemap[p.name]
- del self.pidmap[pid]
+ p.process.returncode = status
if p.callback is not None:
- p.callback(p)
- if p.persist:
- self.call(p.name, p.callback, True, *p.args, **p.kw)
+ log.debug(u'ProcessManager.sigchild_handler: '
+ u'calling %s(%s)', p.callback.__name__, p)
+ p.callback(self, p)
+ if (p._dont_run or not p.persist
+ or p._error_count >= p.max_errors):
+ log.debug(u"ProcessManager.sigchild_handler: can't "
+ u'persist, dont_run=%s, persist=%s, error_cout=%s, '
+ u'max_errors=%s', p._dont_run, p.persist,
+ p._error_count, p.max_errors)
+ del self.namemap[p.name]
+ del self.pidmap[pid]
+ p.clear()
+ else:
+ log.debug(u'ProcessManager.sigchild_handler: persist')
+ if p.process.returncode == 0:
+ p._error_count = 0
+ log.debug(u'ProcessManager.sigchild_handler: '
+ u'return OK, resetting error_count')
+ else:
+ p._error_count += 1
+ log.debug(u'ProcessManager.sigchild_handler: return'
+ u'not 0, error_count + 1 = %s', p._error_count)
+ del self.pidmap[pid]
+ p.restart()
+ self.pidmap[p.process.pid] = p
try:
(pid, status) = os.waitpid(-1, os.WNOHANG)
except OSError, e:
return
raise
- def __getitem__(self, name):
+ def get(self, name):
if isinstance(name, basestring): # is a name
- return self.namemap[name]
+ if name in self.namemap:
+ return self.namemap[name]
+ if name in self.services:
+ return self.services[name]
else: # is a pid
- return self.pidmap[name]
+ if name in self.pidmap:
+ return self.pidmap[name]
+ raise KeyError, name
+ # Syntax sugar for self[name]
+ __getitem__ = get
- def __contains__(self, name):
+ def has(self, name):
if isinstance(name, basestring): # is a name
- return name in self.namemap
+ if name in self.namemap:
+ return True
+ if name in self.services:
+ return True
else: # is a pid
- return name in self.pidmap
+ if name in self.pidmap:
+ return True
+ return False
+ # Syntax sugar for name in self
+ __contains__ = has
+
+
+if __name__ == '__main__':
+ logging.basicConfig(
+ level = logging.DEBUG,
+ format = '%(asctime)s %(levelname)-8s %(message)s',
+ datefmt = '%H:%M:%S',
+ )
+
+
+# Globals
+manager = ProcessManager()
+register = manager.register
+unregister = manager.unregister
+once = manager.once
+start = manager.start
+stop = manager.stop
+restart = manager.restart
+kill = manager.kill
+get = manager.get
+has = manager.has
+sigchild_handler = manager.sigchild_handler
if __name__ == '__main__':
import time
sig = None
+ count = 0
- def sigchild_handler(signum, stacktrace):
+ def SIGCHLD_handler(signum, stacktrace):
global sig
sig = signum
print 'SIGCHLD', signum
- def test_notify(proc):
- print 'test died:', proc, proc.name, proc.process.pid
+ def notify(pm, pi):
+ global count
+ if pi.name == 'test-service':
+ print 'test-service count =', count
+ count += 1
+ if count > 4:
+ print 'set test-service non-persistent, start test-service-2'
+ pi.persist = False
+ assert 'test-service-2' not in manager.namemap
+ pm.start('test-service-2')
+ assert 'test-service-2' in manager.namemap
+ assert get('test-service-2').running
+ print 'died:', pi.name, pi.command
- procman = ProcessManager()
+ register('test-service', ('sleep', '2'), notify, True)
+ assert 'test-service' in manager.services
+ assert 'test-service' not in manager.namemap
+ assert not get('test-service').running
+ assert manager['test-service'] == get('test-service')
+ assert has('test-service')
+ assert 'test-service' in manager
- signal.signal(signal.SIGCHLD, sigchild_handler)
+ register('test-service-2', ('sleep', '3'), notify, False)
+ assert 'test-service-2' in manager.services
+ assert 'test-service-2' not in manager.namemap
+ assert not get('test-service-2').running
- procman.call('test', test_notify, True, ('sleep', '5'))
+ signal.signal(signal.SIGCHLD, SIGCHLD_handler)
- while True:
- time.sleep(1)
- print "Esperando...",
- if 'test' in procman:
- print procman['test']
- else:
- print
+ once('test-once', ('sleep', '5'), notify)
+ assert 'test-once' not in manager.services
+ assert 'test-once' in manager.namemap
+ assert get('test-once').running
+ assert get('test-once').process.pid
+ pid = get('test-once').process.pid
+ restart('test-once')
+ assert pid != get('test-once').process.pid
+ assert pid != manager.pidmap[get('test-once').process.pid].process.pid
+
+ start('test-service')
+ assert 'test-service' in manager.namemap
+ assert get('test-service').running
+ assert get('test-service').process.pid
+ pid = get('test-service').process.pid
+ restart('test-service')
+ assert pid != get('test-service').process.pid
+ assert pid != manager.pidmap[get('test-service').process.pid].process.pid
+
+ print "Known processes:", manager.services.keys()
+ print "Waiting...", manager.namemap.keys()
+ print "------------------------------------------------------------------"
+ while manager.pidmap:
+ signal.pause()
if sig == signal.SIGCHLD:
+ sigchild_handler(sig)
sig = None
- procman.sigchild_handler(sig)
+ print "Known processes:", manager.services.keys()
+ print "Waiting...", manager.namemap.keys()
+ print "------------------------------------------------------------------"
+ assert 'test-service' not in manager.namemap
+ assert 'test-service-2' not in manager.namemap
+ assert 'test-once' not in manager.services
+ assert 'test-once' not in manager.namemap
+
+ restart('test-service')
+ assert get('test-service').process.pid
+ assert manager.pidmap[get('test-service').process.pid].process.pid
+
+ once('test-wait', ('sleep', '2'))
+ print 'test-wait running?', get('test-wait').running
+ assert get('test-wait').running
+ print 'Waiting test-wait to return...'
+ ret = get('test-wait').process.wait()
+ print 'Done! returned:', ret
projects / software / pymin.git / blobdiff