X-Git-Url: https://git.llucax.com/software/pymin.git/blobdiff_plain/c6010d17b74d9b70ba68b8f4567229c92a868f46..a07cee69d1eb6575dd4534bc56e014a08e10bb8a:/pymin/procman.py?ds=inline diff --git a/pymin/procman.py b/pymin/procman.py index 423ace0..269117b 100644 --- a/pymin/procman.py +++ b/pymin/procman.py @@ -2,48 +2,213 @@ 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: @@ -51,17 +216,53 @@ class ProcessManager: 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__': @@ -70,29 +271,85 @@ 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