celery.platforms

celery.platforms

Utilities dealing with platform specifics: signals, daemonization, users, groups, and so on.

celery.platforms.pyimplementation()[源代码]

Return string identifying the current Python implementation.

exception celery.platforms.LockFailed[源代码]

Raised if a pidlock can’t be acquired.

celery.platforms.get_fdmax(default=None)[源代码]

Return the maximum number of open file descriptors on this system.

参数:default – Value returned if there’s no file descriptor limit.

class celery.platforms.Pidfile(path)[源代码]

Pidfile

This is the type returned by create_pidlock().

TIP: Use the create_pidlock() function instead, which is more convenient and also removes stale pidfiles (when the process holding the lock is no longer running).

celery.platforms.create_pidlock(pidfile)[源代码]

Create and verify pidfile.

If the pidfile already exists the program exits with an error message, however if the process it refers to is not running anymore, the pidfile is deleted and the program continues.

This function will automatically install an atexit handler to release the lock at exit, you can skip this by calling _create_pidlock() instead.

返回:Pidfile.

Example:

  1. pidlock = create_pidlock('/var/run/app.pid')

celery.platforms.close_open_fds(keep=None)

class celery.platforms.DaemonContext(pidfile=None, workdir=None, umask=None, fake=False, after_chdir=None, \*kwargs*)[源代码]

celery.platforms.detached(logfile=None, pidfile=None, uid=None, gid=None, umask=0, workdir=None, fake=False, \*opts*)[源代码]

Detach the current process in the background (daemonize).

参数:
  • logfile – Optional log file. The ability to write to this file will be verified before the process is detached.
  • pidfile – Optional pidfile. The pidfile will not be created, as this is the responsibility of the child. But the process will exit if the pid lock exists and the pid written is still running.
  • uid – Optional user id or user name to change effective privileges to.
  • gid – Optional group id or group name to change effective privileges to.
  • umask – Optional umask that will be effective in the child process.
  • workdir – Optional new working directory.
  • fake – Don’t actually detach, intented for debugging purposes.
  • **opts – Ignored.

Example:

  1. from celery.platforms import detached, create_pidlock
  2. with detached(logfile='/var/log/app.log', pidfile='/var/run/app.pid',
  3. uid='nobody'):
  4. # Now in detached child process with effective user set to nobody,
  5. # and we know that our logfile can be written to, and that
  6. # the pidfile is not locked.
  7. pidlock = create_pidlock('/var/run/app.pid')
  8. # Run the program
  9. program.run(logfile='/var/log/app.log')

celery.platforms.parse_uid(uid)[源代码]

Parse user id.

uid can be an integer (uid) or a string (user name), if a user name the uid is taken from the system user registry.

celery.platforms.parse_gid(gid)[源代码]

Parse group id.

gid can be an integer (gid) or a string (group name), if a group name the gid is taken from the system group registry.

celery.platforms.setgroups(groups)[源代码]

Set active groups from a list of group ids.

celery.platforms.initgroups(uid, gid)[源代码]

Compat version of os.initgroups() which was first added to Python 2.7.

celery.platforms.setgid(gid)[源代码]

Version of os.setgid() supporting group names.

celery.platforms.setuid(uid)[源代码]

Version of os.setuid() supporting usernames.

celery.platforms.maybe_drop_privileges(uid=None, gid=None)[源代码]

Change process privileges to new user/group.

If UID and GID is specified, the real user/group is changed.

If only UID is specified, the real user is changed, and the group is changed to the users primary group.

If only GID is specified, only the group is changed.

celery.platforms.set_process_title(progname, info=None)[源代码]

Set the ps name for the currently running process.

Only works if setproctitle is installed.

celery.platforms.set_mp_process_title(progname, info=None, hostname=None)[源代码]

Set the ps name using the multiprocessing process name.

Only works if setproctitle is installed.

celery.platforms.get_errno_name(n)

Get errno for string, e.g. ENOENT.

celery.platforms.ignore_errno(\args, **kwds*)[源代码]

Context manager to ignore specific POSIX error codes.

Takes a list of error codes to ignore, which can be either the name of the code, or the code integer itself:

  1. >>> with ignore_errno('ENOENT'):
  2. ... with open('foo', 'r') as fh:
  3. ... return fh.read()
  4. >>> with ignore_errno(errno.ENOENT, errno.EPERM):
  5. ... pass
参数:types – A tuple of exceptions to ignore (when the errno matches), defaults to Exception.