This document describes the current stable version of Celery (5.4). For development docs, go here.

Source code for celery.bin.multi

"""Start multiple worker instances from the command-line.

.. program:: celery multi


.. code-block:: console

    $ # Single worker with explicit name and events enabled.
    $ celery multi start Leslie -E

    $ # Pidfiles and logfiles are stored in the current directory
    $ # by default.  Use --pidfile and --logfile argument to change
    $ # this.  The abbreviation %n will be expanded to the current
    $ # node name.
    $ celery multi start Leslie -E --pidfile=/var/run/celery/

    $ # You need to add the same arguments when you restart,
    $ # as these aren't persisted anywhere.
    $ celery multi restart Leslie -E --pidfile=/var/run/celery/

    $ # To stop the node, you need to specify the same pidfile.
    $ celery multi stop Leslie --pidfile=/var/run/celery/

    $ # 3 workers, with 3 processes each
    $ celery multi start 3 -c 3
    celery worker -n celery1@myhost -c 3
    celery worker -n celery2@myhost -c 3
    celery worker -n celery3@myhost -c 3

    $ # override name prefix when using range
    $ celery multi start 3 --range-prefix=worker -c 3
    celery worker -n worker1@myhost -c 3
    celery worker -n worker2@myhost -c 3
    celery worker -n worker3@myhost -c 3

    $ # start 3 named workers
    $ celery multi start image video data -c 3
    celery worker -n image@myhost -c 3
    celery worker -n video@myhost -c 3
    celery worker -n data@myhost -c 3

    $ # specify custom hostname
    $ celery multi start 2 -c 3
    celery worker -n -c 3
    celery worker -n -c 3

    $ # specify fully qualified nodenames
    $ celery multi start -c 3

    $ # fully qualified nodenames but using the current hostname
    $ celery multi start foo@%h bar@%h

    $ # Advanced example starting 10 workers in the background:
    $ #   * Three of the workers processes the images and video queue
    $ #   * Two of the workers processes the data queue with loglevel DEBUG
    $ #   * the rest processes the default' queue.
    $ celery multi start 10 -l INFO -Q:1-3 images,video -Q:4,5 data
        -Q default -L:4,5 DEBUG

    $ # You can show the commands necessary to start the workers with
    $ # the 'show' command:
    $ celery multi show 10 -l INFO -Q:1-3 images,video -Q:4,5 data
        -Q default -L:4,5 DEBUG

    $ # Additional options are added to each celery worker's command,
    $ # but you can also modify the options for ranges of, or specific workers

    $ # 3 workers: Two with 3 processes, and one with 10 processes.
    $ celery multi start 3 -c 3 -c:1 10
    celery worker -n celery1@myhost -c 10
    celery worker -n celery2@myhost -c 3
    celery worker -n celery3@myhost -c 3

    $ # can also specify options for named workers
    $ celery multi start image video data -c 3 -c:image 10
    celery worker -n image@myhost -c 10
    celery worker -n video@myhost -c 3
    celery worker -n data@myhost -c 3

    $ # ranges and lists of workers in options is also allowed:
    $ # (-c:1-3 can also be written as -c:1,2,3)
    $ celery multi start 5 -c 3  -c:1-3 10
    celery worker -n celery1@myhost -c 10
    celery worker -n celery2@myhost -c 10
    celery worker -n celery3@myhost -c 10
    celery worker -n celery4@myhost -c 3
    celery worker -n celery5@myhost -c 3

    $ # lists also works with named workers
    $ celery multi start foo bar baz xuzzy -c 3 -c:foo,bar,baz 10
    celery worker -n foo@myhost -c 10
    celery worker -n bar@myhost -c 10
    celery worker -n baz@myhost -c 10
    celery worker -n xuzzy@myhost -c 3
import os
import signal
import sys
from functools import wraps

import click
from kombu.utils.objects import cached_property

from celery import VERSION_BANNER
from celery.apps.multi import Cluster, MultiParser, NamespacedOptionParser
from celery.bin.base import CeleryCommand, handle_preload_options
from celery.platforms import EX_FAILURE, EX_OK, signals
from celery.utils import term
from celery.utils.text import pluralize

__all__ = ('MultiTool',)

USAGE = """\
usage: {prog_name} start <node1 node2 nodeN|range> [worker options]
       {prog_name} stop <n1 n2 nN|range> [-SIG (default: -TERM)]
       {prog_name} restart <n1 n2 nN|range> [-SIG] [worker options]
       {prog_name} kill <n1 n2 nN|range>

       {prog_name} show <n1 n2 nN|range> [worker options]
       {prog_name} get hostname <n1 n2 nN|range> [-qv] [worker options]
       {prog_name} names <n1 n2 nN|range>
       {prog_name} expand template <n1 n2 nN|range>
       {prog_name} help

additional options (must appear after command name):

    * --nosplash:   Don't display program info.
    * --quiet:      Don't show as much output.
    * --verbose:    Show more output.
    * --no-color:   Don't display colors.

def main():

def splash(fun):

    def _inner(self, *args, **kwargs):
        return fun(self, *args, **kwargs)
    return _inner

def using_cluster(fun):

    def _inner(self, *argv, **kwargs):
        return fun(self, self.cluster_from_argv(argv), **kwargs)
    return _inner

def using_cluster_and_sig(fun):

    def _inner(self, *argv, **kwargs):
        p, cluster = self._cluster_from_argv(argv)
        sig = self._find_sig_argument(p)
        return fun(self, cluster, sig, **kwargs)
    return _inner

class TermLogger:

    splash_text = 'celery multi v{version}'
    splash_context = {'version': VERSION_BANNER}

    #: Final exit code.
    retcode = 0

    def setup_terminal(self, stdout, stderr,
                       nosplash=False, quiet=False, verbose=False,
                       no_color=False, **kwargs):
        self.stdout = stdout or sys.stdout
        self.stderr = stderr or sys.stderr
        self.nosplash = nosplash
        self.quiet = quiet
        self.verbose = verbose
        self.no_color = no_color

    def ok(self, m, newline=True, file=None):
        self.say(m, newline=newline, file=file)
        return EX_OK

    def say(self, m, newline=True, file=None):
        print(m, file=file or self.stdout, end='\n' if newline else '')

    def carp(self, m, newline=True, file=None):
        return self.say(m, newline, file or self.stderr)

    def error(self, msg=None):
        if msg:
        return EX_FAILURE

    def info(self, msg, newline=True):
        if self.verbose:
            self.note(msg, newline=newline)

    def note(self, msg, newline=True):
        if not self.quiet:
            self.say(str(msg), newline=newline)

    def usage(self):

    def splash(self):
        if not self.nosplash:

    def colored(self):
        return term.colored(enabled=not self.no_color)

[docs] class MultiTool(TermLogger): """The ``celery multi`` program.""" MultiParser = MultiParser OptionParser = NamespacedOptionParser reserved_options = [ ('--nosplash', 'nosplash'), ('--quiet', 'quiet'), ('-q', 'quiet'), ('--verbose', 'verbose'), ('--no-color', 'no_color'), ] def __init__(self, env=None, cmd=None, fh=None, stdout=None, stderr=None, **kwargs): # fh is an old alias to stdout. self.env = env self.cmd = cmd self.setup_terminal(stdout or fh, stderr, **kwargs) self.fh = self.stdout self.prog_name = 'celery multi' self.commands = { 'start': self.start, 'show':, 'stop': self.stop, 'stopwait': self.stopwait, 'stop_verify': self.stopwait, # compat alias 'restart': self.restart, 'kill': self.kill, 'names': self.names, 'expand': self.expand, 'get': self.get, 'help':, }
[docs] def execute_from_commandline(self, argv, cmd=None): # Reserve the --nosplash|--quiet|-q/--verbose options. argv = self._handle_reserved_options(argv) self.cmd = cmd if cmd is not None else self.cmd self.prog_name = os.path.basename(argv.pop(0)) if not self.validate_arguments(argv): return self.error() return self.call_command(argv[0], argv[1:])
[docs] def validate_arguments(self, argv): return argv and argv[0][0] != '-'
[docs] def call_command(self, command, argv): try: return self.commands[command](*argv) or EX_OK except KeyError: return self.error(f'Invalid command: {command}')
def _handle_reserved_options(self, argv): argv = list(argv) # don't modify callers argv. for arg, attr in self.reserved_options: if arg in argv: setattr(self, attr, bool(argv.pop(argv.index(arg)))) return argv
[docs] @splash @using_cluster def start(self, cluster): self.note('> Starting nodes...') return int(any(cluster.start()))
[docs] @splash @using_cluster_and_sig def stop(self, cluster, sig, **kwargs): return cluster.stop(sig=sig, **kwargs)
[docs] @splash @using_cluster_and_sig def stopwait(self, cluster, sig, **kwargs): return cluster.stopwait(sig=sig, **kwargs)
stop_verify = stopwait # compat
[docs] @splash @using_cluster_and_sig def restart(self, cluster, sig, **kwargs): return int(any(cluster.restart(sig=sig, **kwargs)))
[docs] @using_cluster def names(self, cluster): self.say('\n'.join( for n in cluster))
[docs] def get(self, wanted, *argv): try: node = self.cluster_from_argv(argv).find(wanted) except KeyError: return EX_FAILURE else: return self.ok(' '.join(node.argv))
[docs] @using_cluster def show(self, cluster): return self.ok('\n'.join( ' '.join(node.argv_with_executable) for node in cluster ))
[docs] @splash @using_cluster def kill(self, cluster): return cluster.kill()
[docs] def expand(self, template, *argv): return self.ok('\n'.join( node.expander(template) for node in self.cluster_from_argv(argv) ))
[docs] def help(self, *argv): self.say(__doc__)
def _find_sig_argument(self, p, default=signal.SIGTERM): args = p.args[len(p.values):] for arg in reversed(args): if len(arg) == 2 and arg[0] == '-': try: return int(arg[1]) except ValueError: pass if arg[0] == '-': try: return signals.signum(arg[1:]) except (AttributeError, TypeError): pass return default def _nodes_from_argv(self, argv, cmd=None): cmd = cmd if cmd is not None else self.cmd p = self.OptionParser(argv) p.parse() return p, self.MultiParser(cmd=cmd).parse(p)
[docs] def cluster_from_argv(self, argv, cmd=None): _, cluster = self._cluster_from_argv(argv, cmd=cmd) return cluster
def _cluster_from_argv(self, argv, cmd=None): p, nodes = self._nodes_from_argv(argv, cmd=cmd) return p, self.Cluster(list(nodes), cmd=cmd)
[docs] def Cluster(self, nodes, cmd=None): return Cluster( nodes, cmd=cmd, env=self.env, on_stopping_preamble=self.on_stopping_preamble, on_send_signal=self.on_send_signal, on_still_waiting_for=self.on_still_waiting_for, on_still_waiting_progress=self.on_still_waiting_progress, on_still_waiting_end=self.on_still_waiting_end, on_node_start=self.on_node_start, on_node_restart=self.on_node_restart, on_node_shutdown_ok=self.on_node_shutdown_ok, on_node_status=self.on_node_status, on_node_signal_dead=self.on_node_signal_dead, on_node_signal=self.on_node_signal, on_node_down=self.on_node_down, on_child_spawn=self.on_child_spawn, on_child_signalled=self.on_child_signalled, on_child_failure=self.on_child_failure, )
[docs] def on_stopping_preamble(self, nodes): self.note('> Stopping nodes...'))
[docs] def on_send_signal(self, node, sig): self.note('\t> {}: {1} -> {}'.format(node, sig))
[docs] def on_still_waiting_for(self, nodes): num_left = len(nodes) if num_left: self.note( '> Waiting for {} {} -> {}...'.format( num_left, pluralize(num_left, 'node'), ', '.join(str( for node in nodes)), ), newline=False)
[docs] def on_still_waiting_progress(self, nodes): self.note('.', newline=False)
[docs] def on_still_waiting_end(self): self.note('')
[docs] def on_node_signal_dead(self, node): self.note( 'Could not signal {} ({}): No such process'.format( node))
[docs] def on_node_start(self, node): self.note(f'\t> {}: ', newline=False)
[docs] def on_node_restart(self, node): self.note( f'> Restarting node {}: '), newline=False)
[docs] def on_node_down(self, node): self.note(f'> {}: {self.DOWN}')
[docs] def on_node_shutdown_ok(self, node): self.note(f'\n\t> {}: {self.OK}')
[docs] def on_node_status(self, node, retval): self.note(retval and self.FAILED or self.OK)
[docs] def on_node_signal(self, node, sig): self.note('Sending {sig} to node {} ({})'.format( node, sig=sig))
[docs] def on_child_spawn(self, node, argstr, env):' {argstr}')
[docs] def on_child_signalled(self, node, signum): self.note(f'* Child was terminated by signal {signum}')
[docs] def on_child_failure(self, node, retcode): self.note(f'* Child terminated with exit code {retcode}')
@cached_property def OK(self): return str('OK')) @cached_property def FAILED(self): return str('FAILED')) @cached_property def DOWN(self): return str(self.colored.magenta('DOWN'))
@click.command( cls=CeleryCommand, context_settings={ 'allow_extra_args': True, 'ignore_unknown_options': True } ) @click.pass_context @handle_preload_options def multi(ctx, **kwargs): """Start multiple worker instances.""" cmd = MultiTool(quiet=ctx.obj.quiet, no_color=ctx.obj.no_color) # In 4.x, celery multi ignores the global --app option. # Since in 5.0 the --app option is global only we # rearrange the arguments so that the MultiTool will parse them correctly. args = sys.argv[1:] args = args[args.index('multi'):] + args[:args.index('multi')] return cmd.execute_from_commandline(args)