twisted.runner.procmon.ProcessMonitor

ProcessMonitor runs processes, monitors their progress, and restarts them when they die.

The ProcessMonitor will not attempt to restart a process that appears to die instantly -- with each "instant" death (less than 1 second, by default), it will delay approximately twice as long before restarting it. A successful run will reset the counter.

The primary interface is addProcess and removeProcess. When the service is running (that is, when the application it is attached to is running), adding a process automatically starts it.

Each process has a name. This name string must uniquely identify the process. In particular, attempting to add two processes with the same name will result in a KeyError.

Instance Variable	threshold	How long a process has to live before the death is considered instant, in seconds. The default value is 1 second. (type: `float`)
Instance Variable	killTime	How long a process being killed has to get its affairs in order before it gets killed with an unmaskable signal. The default value is 5 seconds. (type: `float`)
Instance Variable	minRestartDelay	The minimum time (in seconds) to wait before attempting to restart a process. Default 1s. (type: `float`)
Instance Variable	maxRestartDelay	The maximum time (in seconds) to wait before attempting to restart a process. Default 3600s (1h). (type: `float`)
Instance Variable	log	The logger used to propagate log messages from spawned processes. (type: `Logger`)
Method	__init__	Undocumented
Method	processes	Processes as dict of tuples
Method	__getstate__	Undocumented
Method	addProcess	Add a new monitored process and start it immediately if the `ProcessMonitor` service is running.
Method	removeProcess	Stop the named process and remove it from the list of monitored processes.
Method	startService	Start all monitored processes.
Method	stopService	Stop all monitored processes and cancel all scheduled process restarts.
Method	connectionLost	No summary
Method	startProcess
Method	stopProcess
Method	restartAll	No summary
Method	__repr__	Undocumented
Instance Variable	_reactor	A provider of `IReactorProcess` and `IReactorTime` which will be used to spawn processes and register delayed calls. (type: `IReactorProcess` provider)
Method	_forceStopProcess

Inherited from Service:

Method	setName	Set the name of the service.
Method	setServiceParent	Set the parent of the service. This method is responsible for setting the `parent` attribute on this service (the child service).
Method	disownServiceParent	Use this API to remove an `IService` from an `IServiceCollection`.
Method	privilegedStartService	Do preparation work for starting the service.

threshold =

How long a process has to live before the death is considered instant, in seconds. The default value is 1 second. (type: float)

killTime =

How long a process being killed has to get its affairs in order before it gets killed with an unmaskable signal. The default value is 5 seconds. (type: float)

minRestartDelay =

The minimum time (in seconds) to wait before attempting to restart a process. Default 1s. (type: float)

maxRestartDelay =

The maximum time (in seconds) to wait before attempting to restart a process. Default 3600s (1h). (type: float)

_reactor =

A provider of IReactorProcess and IReactorTime which will be used to spawn processes and register delayed calls. (type: IReactorProcess provider)

log =

The logger used to propagate log messages from spawned processes. (type: Logger)

def __init__(self, reactor=_reactor):

Undocumented

@deprecate.deprecatedProperty(incremental.Version('Twisted', 18, 7, 0))
def processes(self):

Processes as dict of tuples

Returns Dict of process name to monitored processes as tuples

@deprecate.deprecated(incremental.Version('Twisted', 18, 7, 0))
def __getstate__(self):

overrides twisted.application.service.Service.__getstate__

Undocumented

def addProcess(self, name, args, uid=None, gid=None, env={}, cwd=None):

Add a new monitored process and start it immediately if the ProcessMonitor service is running.

Note that args are passed to the system call, not to the shell. If running the shell is desired, the common idiom is to use ProcessMonitor.addProcess("name", ['/bin/sh', '-c', shell_script])

Parameters	name	A name for this process. This value must be unique across all processes added to this monitor. (type: `str`)
	args	The argv sequence for the process to launch.
	uid	The user ID to use to run the process. If `None`, the current UID is used. (type: `int`)
	gid	The group ID to use to run the process. If `None`, the current GID is used.
	env	The environment to give to the launched process. See `IReactorProcess.spawnProcess`'s `env` parameter. (type: `dict`)
	cwd	The initial working directory of the launched process. The default of `None` means inheriting the laucnhing process's working directory.
Raises	`KeyError` if a process with the given name already exists

def removeProcess(self, name):

Stop the named process and remove it from the list of monitored processes.

Parameters name A string that uniquely identifies the process. (type: str)

def startService(self):

from twisted.application.service.IService

overrides twisted.application.service.Service.startService

Start all monitored processes.

def stopService(self):

from twisted.application.service.IService

overrides twisted.application.service.Service.stopService

Stop all monitored processes and cancel all scheduled process restarts.

def connectionLost(self, name):

Called when a monitored processes exits. If service.IService.running is True (ie the service is started), the process will be restarted. If the process had been running for more than ProcessMonitor.threshold seconds it will be restarted immediately. If the process had been running for less than ProcessMonitor.threshold seconds, the restart will be delayed and each time the process dies before the configured threshold, the restart delay will be doubled - up to a maximum delay of maxRestartDelay sec.

Parameters name A string that uniquely identifies the process which exited. (type: str)

def startProcess(self, name):

Parameters name The name of the process to be started

def _forceStopProcess(self, proc):

Parameters proc An IProcessTransport provider

def stopProcess(self, name):

Parameters name The name of the process to be stopped

def restartAll(self):

Restart all processes. This is useful for third party management services to allow a user to restart servers because of an outside change in circumstances -- for example, a new version of a library is installed.

def __repr__(self):

Undocumented

API Documentation for twisted, generated by pydoctor at 2020-03-25 17:34:30.

twisted.runner.procmon.ProcessMonitor(service.Service) class documentation

`twisted.runner.procmon.ProcessMonitor(service.Service)` class documentation