twisted.scripts._twistd_unix.UnixApplicationRunner

class documentation

class UnixApplicationRunner(app.ApplicationRunner): (source)

An ApplicationRunner which does Unix-specific things, like fork, shed privileges, and maintain a PID file.

Method	`daemonize`	Daemonizes the application on Unix. This is done by the usual double forking approach.
Method	`postApplication`	To be called after the application is created: start the application and run the reactor. After the reactor stops, clean up PID files and such.
Method	`preApplication`	Do pre-application-creation setup.
Method	`removePID`	Remove the specified PID file, if possible. Errors are logged, not raised.
Method	`setupEnvironment`	Set the filesystem root, the working directory, and daemonize.
Method	`shedPrivileges`	Change the UID and GID or the EUID and EGID of this process.
Method	`startApplication`	Configure global process state based on the given application and run the application.
Instance Variable	`oldstderr`	Undocumented
Instance Variable	`oldstdout`	Undocumented
Method	`_formatChildException`	No summary
Method	`_waitForStart`	Wait for the daemonization success.

Inherited from ApplicationRunner:

Method	`__init__`	Undocumented
Method	`createOrGetApplication`	Create or load an Application based on the parameters found in the given `ServerOptions` instance.
Method	`run`	Run the application.
Method	`startReactor`	Run the reactor with the given configuration. Subclasses should probably call this from `postApplication`.
Instance Variable	`application`	Available in postApplication, but not preApplication. This is the application object.
Instance Variable	`config`	The config object, which provides a dict-like interface.
Instance Variable	`logger`	Instance provided by `loggerFactory`.
Instance Variable	`loggerFactory`	Factory for creating object responsible for logging.
Instance Variable	`profiler`	Instance provided by `profilerFactory`.
Instance Variable	`profilerFactory`	Factory for creating a profiler object, able to profile the application if options are set accordingly.
Instance Variable	`_exitSignal`	Undocumented

def daemonize(self, reactor): (source)

Daemonizes the application on Unix. This is done by the usual double forking approach.

Parameters
reactor	The reactor in use. If it provides `IReactorDaemonize`, its daemonization-related callbacks will be invoked.
Returns
`int`	A writable pipe to be used to report errors.
See Also
http://code.activestate.com/recipes/278731/
W. Richard Stevens, "Advanced Programming in the Unix Environment", 1992, Addison-Wesley, ISBN 0-201-56317-7

def postApplication(self): (source)

overrides twisted.application.app.ApplicationRunner.postApplication

To be called after the application is created: start the application and run the reactor. After the reactor stops, clean up PID files and such.

def preApplication(self): (source)

overrides twisted.application.app.ApplicationRunner.preApplication

Do pre-application-creation setup.

def removePID(self, pidfile): (source)

Remove the specified PID file, if possible. Errors are logged, not raised.

Parameters
pidfile:`str`	The path to the PID tracking file.

def setupEnvironment(self, chroot, rundir, nodaemon, umask, pidfile): (source)

Set the filesystem root, the working directory, and daemonize.

Parameters
chroot:`str` or `None`	If not None, a path to use as the filesystem root (using `os.chroot`).
rundir:`str`	The path to set as the working directory.
nodaemon:`bool`	A flag which, if set, indicates that daemonization should not be done.
umask:`int` or `None`	The value to which to change the process umask.
pidfile:`str` or `None`	If not `None`, the path to a file into which to put the PID of this process.

def shedPrivileges(self, euid, uid, gid): (source)

Change the UID and GID or the EUID and EGID of this process.

Parameters
euid:`bool`	A flag which, if set, indicates that only the effective UID and GID should be set.
uid:`int` or `None`	If not `None`, the UID to which to switch.
gid:`int` or `None`	If not `None`, the GID to which to switch.

def startApplication(self, application): (source)

Configure global process state based on the given application and run the application.

Parameters
application	An object which can be adapted to `service.IProcess` and `service.IService`.

oldstderr = (source)

Undocumented

oldstdout = (source)

Undocumented

def _formatChildException(self, exception): (source)

Format the exception in preparation for writing to the status pipe. This does the right thing on Python 2 if the exception's message is Unicode, and in all cases limits the length of the message afte* encoding to 100 bytes.

This means the returned message may be truncated in the middle of a unicode escape.

Parameters
exception:`Exception`	The exception to format.
Returns
`bytes`	The formatted message, suitable for writing to the status pipe.

def _waitForStart(self, readPipe): (source)

Wait for the daemonization success.

Parameters
readPipe:`int`	file descriptor to read start information from.
Returns
`int`	code to be passed to `os._exit`: 0 for success, 1 for error.