This file is indexed.

/usr/lib/python2.7/dist-packages/celery/bin/celery.py is in python-celery 3.1.20-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
# -*- coding: utf-8 -*-
"""

The :program:`celery` umbrella command.

.. program:: celery

"""
from __future__ import absolute_import, unicode_literals

import anyjson
import numbers
import os
import sys

from functools import partial
from importlib import import_module

from celery.five import string_t, values
from celery.platforms import EX_OK, EX_FAILURE, EX_UNAVAILABLE, EX_USAGE
from celery.utils import term
from celery.utils import text
from celery.utils.timeutils import maybe_iso8601

# Cannot use relative imports here due to a Windows issue (#1111).
from celery.bin.base import Command, Option, Extensions

# Import commands from other modules
from celery.bin.amqp import amqp
from celery.bin.beat import beat
from celery.bin.events import events
from celery.bin.graph import graph
from celery.bin.worker import worker

__all__ = ['CeleryCommand', 'main']

HELP = """
---- -- - - ---- Commands- -------------- --- ------------

{commands}
---- -- - - --------- -- - -------------- --- ------------

Type '{prog_name} <command> --help' for help using a specific command.
"""

MIGRATE_PROGRESS_FMT = """\
Migrating task {state.count}/{state.strtotal}: \
{body[task]}[{body[id]}]\
"""

DEBUG = os.environ.get('C_DEBUG', False)

command_classes = [
    ('Main', ['worker', 'events', 'beat', 'shell', 'multi', 'amqp'], 'green'),
    ('Remote Control', ['status', 'inspect', 'control'], 'blue'),
    ('Utils', ['purge', 'list', 'migrate', 'call', 'result', 'report'], None),
]
if DEBUG:  # pragma: no cover
    command_classes.append(
        ('Debug', ['graph'], 'red'),
    )


def determine_exit_status(ret):
    if isinstance(ret, numbers.Integral):
        return ret
    return EX_OK if ret else EX_FAILURE


def main(argv=None):
    # Fix for setuptools generated scripts, so that it will
    # work with multiprocessing fork emulation.
    # (see multiprocessing.forking.get_preparation_data())
    try:
        if __name__ != '__main__':  # pragma: no cover
            sys.modules['__main__'] = sys.modules[__name__]
        cmd = CeleryCommand()
        cmd.maybe_patch_concurrency()
        from billiard import freeze_support
        freeze_support()
        cmd.execute_from_commandline(argv)
    except KeyboardInterrupt:
        pass


class multi(Command):
    """Start multiple worker instances."""
    respects_app_option = False

    def get_options(self):
        return ()

    def run_from_argv(self, prog_name, argv, command=None):
        from celery.bin.multi import MultiTool
        multi = MultiTool(quiet=self.quiet, no_color=self.no_color)
        return multi.execute_from_commandline(
            [command] + argv, prog_name,
        )


class list_(Command):
    """Get info from broker.

    Examples::

        celery list bindings

    NOTE: For RabbitMQ the management plugin is required.
    """
    args = '[bindings]'

    def list_bindings(self, management):
        try:
            bindings = management.get_bindings()
        except NotImplementedError:
            raise self.Error('Your transport cannot list bindings.')

        def fmt(q, e, r):
            return self.out('{0:<28} {1:<28} {2}'.format(q, e, r))
        fmt('Queue', 'Exchange', 'Routing Key')
        fmt('-' * 16, '-' * 16, '-' * 16)
        for b in bindings:
            fmt(b['destination'], b['source'], b['routing_key'])

    def run(self, what=None, *_, **kw):
        topics = {'bindings': self.list_bindings}
        available = ', '.join(topics)
        if not what:
            raise self.UsageError(
                'You must specify one of {0}'.format(available))
        if what not in topics:
            raise self.UsageError(
                'unknown topic {0!r} (choose one of: {1})'.format(
                    what, available))
        with self.app.connection() as conn:
            self.app.amqp.TaskConsumer(conn).declare()
            topics[what](conn.manager)


class call(Command):
    """Call a task by name.

    Examples::

        celery call tasks.add --args='[2, 2]'
        celery call tasks.add --args='[2, 2]' --countdown=10
    """
    args = '<task_name>'
    option_list = Command.option_list + (
        Option('--args', '-a', help='positional arguments (json).'),
        Option('--kwargs', '-k', help='keyword arguments (json).'),
        Option('--eta', help='scheduled time (ISO-8601).'),
        Option('--countdown', type='float',
               help='eta in seconds from now (float/int).'),
        Option('--expires', help='expiry time (ISO-8601/float/int).'),
        Option('--serializer', default='json', help='defaults to json.'),
        Option('--queue', help='custom queue name.'),
        Option('--exchange', help='custom exchange name.'),
        Option('--routing-key', help='custom routing key.'),
    )

    def run(self, name, *_, **kw):
        # Positional args.
        args = kw.get('args') or ()
        if isinstance(args, string_t):
            args = anyjson.loads(args)

        # Keyword args.
        kwargs = kw.get('kwargs') or {}
        if isinstance(kwargs, string_t):
            kwargs = anyjson.loads(kwargs)

        # Expires can be int/float.
        expires = kw.get('expires') or None
        try:
            expires = float(expires)
        except (TypeError, ValueError):
            # or a string describing an ISO 8601 datetime.
            try:
                expires = maybe_iso8601(expires)
            except (TypeError, ValueError):
                raise

        res = self.app.send_task(name, args=args, kwargs=kwargs,
                                 countdown=kw.get('countdown'),
                                 serializer=kw.get('serializer'),
                                 queue=kw.get('queue'),
                                 exchange=kw.get('exchange'),
                                 routing_key=kw.get('routing_key'),
                                 eta=maybe_iso8601(kw.get('eta')),
                                 expires=expires)
        self.out(res.id)


class purge(Command):
    """Erase all messages from all known task queues.

    WARNING: There is no undo operation for this command.

    """
    warn_prelude = (
        '{warning}: This will remove all tasks from {queues}: {names}.\n'
        '         There is no undo for this operation!\n\n'
        '(to skip this prompt use the -f option)\n'
    )
    warn_prompt = 'Are you sure you want to delete all tasks'
    fmt_purged = 'Purged {mnum} {messages} from {qnum} known task {queues}.'
    fmt_empty = 'No messages purged from {qnum} {queues}'
    option_list = Command.option_list + (
        Option('--force', '-f', action='store_true',
               help='Do not prompt for verification'),
    )

    def run(self, force=False, **kwargs):
        names = list(sorted(self.app.amqp.queues.keys()))
        qnum = len(names)
        if not force:
            self.out(self.warn_prelude.format(
                warning=self.colored.red('WARNING'),
                queues=text.pluralize(qnum, 'queue'), names=', '.join(names),
            ))
            if self.ask(self.warn_prompt, ('yes', 'no'), 'no') != 'yes':
                return
        messages = self.app.control.purge()
        fmt = self.fmt_purged if messages else self.fmt_empty
        self.out(fmt.format(
            mnum=messages, qnum=qnum,
            messages=text.pluralize(messages, 'message'),
            queues=text.pluralize(qnum, 'queue')))


class result(Command):
    """Gives the return value for a given task id.

    Examples::

        celery result 8f511516-e2f5-4da4-9d2f-0fb83a86e500
        celery result 8f511516-e2f5-4da4-9d2f-0fb83a86e500 -t tasks.add
        celery result 8f511516-e2f5-4da4-9d2f-0fb83a86e500 --traceback

    """
    args = '<task_id>'
    option_list = Command.option_list + (
        Option('--task', '-t', help='name of task (if custom backend)'),
        Option('--traceback', action='store_true',
               help='show traceback instead'),
    )

    def run(self, task_id, *args, **kwargs):
        result_cls = self.app.AsyncResult
        task = kwargs.get('task')
        traceback = kwargs.get('traceback', False)

        if task:
            result_cls = self.app.tasks[task].AsyncResult
        result = result_cls(task_id)
        if traceback:
            value = result.traceback
        else:
            value = result.get()
        self.out(self.pretty(value)[1])


class _RemoteControl(Command):
    name = None
    choices = None
    leaf = False
    option_list = Command.option_list + (
        Option('--timeout', '-t', type='float',
               help='Timeout in seconds (float) waiting for reply'),
        Option('--destination', '-d',
               help='Comma separated list of destination node names.'))

    def __init__(self, *args, **kwargs):
        self.show_body = kwargs.pop('show_body', True)
        self.show_reply = kwargs.pop('show_reply', True)
        super(_RemoteControl, self).__init__(*args, **kwargs)

    @classmethod
    def get_command_info(self, command,
                         indent=0, prefix='', color=None, help=False):
        if help:
            help = '|' + text.indent(self.choices[command][1], indent + 4)
        else:
            help = None
        try:
            # see if it uses args.
            meth = getattr(self, command)
            return text.join([
                '|' + text.indent('{0}{1} {2}'.format(
                    prefix, color(command), meth.__doc__), indent),
                help,
            ])

        except AttributeError:
            return text.join([
                '|' + text.indent(prefix + str(color(command)), indent), help,
            ])

    @classmethod
    def list_commands(self, indent=0, prefix='', color=None, help=False):
        color = color if color else lambda x: x
        prefix = prefix + ' ' if prefix else ''
        return '\n'.join(self.get_command_info(c, indent, prefix, color, help)
                         for c in sorted(self.choices))

    @property
    def epilog(self):
        return '\n'.join([
            '[Commands]',
            self.list_commands(indent=4, help=True)
        ])

    def usage(self, command):
        return '%prog {0} [options] {1} <command> [arg1 .. argN]'.format(
            command, self.args)

    def call(self, *args, **kwargs):
        raise NotImplementedError('call')

    def run(self, *args, **kwargs):
        if not args:
            raise self.UsageError(
                'Missing {0.name} method. See --help'.format(self))
        return self.do_call_method(args, **kwargs)

    def do_call_method(self, args, **kwargs):
        method = args[0]
        if method == 'help':
            raise self.Error("Did you mean '{0.name} --help'?".format(self))
        if method not in self.choices:
            raise self.UsageError(
                'Unknown {0.name} method {1}'.format(self, method))

        if self.app.connection().transport.driver_type == 'sql':
            raise self.Error('Broadcast not supported by SQL broker transport')

        destination = kwargs.get('destination')
        timeout = kwargs.get('timeout') or self.choices[method][0]
        if destination and isinstance(destination, string_t):
            destination = [dest.strip() for dest in destination.split(',')]

        handler = getattr(self, method, self.call)

        replies = handler(method, *args[1:], timeout=timeout,
                          destination=destination,
                          callback=self.say_remote_command_reply)
        if not replies:
            raise self.Error('No nodes replied within time constraint.',
                             status=EX_UNAVAILABLE)
        return replies


class inspect(_RemoteControl):
    """Inspect the worker at runtime.

    Availability: RabbitMQ (amqp), Redis, and MongoDB transports.

    Examples::

        celery inspect active --timeout=5
        celery inspect scheduled -d worker1@example.com
        celery inspect revoked -d w1@e.com,w2@e.com

    """
    name = 'inspect'
    choices = {
        'active': (1.0, 'dump active tasks (being processed)'),
        'active_queues': (1.0, 'dump queues being consumed from'),
        'scheduled': (1.0, 'dump scheduled tasks (eta/countdown/retry)'),
        'reserved': (1.0, 'dump reserved tasks (waiting to be processed)'),
        'stats': (1.0, 'dump worker statistics'),
        'revoked': (1.0, 'dump of revoked task ids'),
        'registered': (1.0, 'dump of registered tasks'),
        'ping': (0.2, 'ping worker(s)'),
        'clock': (1.0, 'get value of logical clock'),
        'conf': (1.0, 'dump worker configuration'),
        'report': (1.0, 'get bugreport info'),
        'memsample': (1.0, 'sample memory (requires psutil)'),
        'memdump': (1.0, 'dump memory samples (requires psutil)'),
        'objgraph': (60.0, 'create object graph (requires objgraph)'),
    }

    def call(self, method, *args, **options):
        i = self.app.control.inspect(**options)
        return getattr(i, method)(*args)

    def objgraph(self, type_='Request', *args, **kwargs):
        return self.call('objgraph', type_, **kwargs)

    def conf(self, with_defaults=False, *args, **kwargs):
        return self.call('conf', with_defaults, **kwargs)


class control(_RemoteControl):
    """Workers remote control.

    Availability: RabbitMQ (amqp), Redis, and MongoDB transports.

    Examples::

        celery control enable_events --timeout=5
        celery control -d worker1@example.com enable_events
        celery control -d w1.e.com,w2.e.com enable_events

        celery control -d w1.e.com add_consumer queue_name
        celery control -d w1.e.com cancel_consumer queue_name

        celery control -d w1.e.com add_consumer queue exchange direct rkey

    """
    name = 'control'
    choices = {
        'enable_events': (1.0, 'tell worker(s) to enable events'),
        'disable_events': (1.0, 'tell worker(s) to disable events'),
        'add_consumer': (1.0, 'tell worker(s) to start consuming a queue'),
        'cancel_consumer': (1.0, 'tell worker(s) to stop consuming a queue'),
        'rate_limit': (
            1.0, 'tell worker(s) to modify the rate limit for a task type'),
        'time_limit': (
            1.0, 'tell worker(s) to modify the time limit for a task type.'),
        'autoscale': (1.0, 'change autoscale settings'),
        'pool_grow': (1.0, 'start more pool processes'),
        'pool_shrink': (1.0, 'use less pool processes'),
    }

    def call(self, method, *args, **options):
        return getattr(self.app.control, method)(*args, reply=True, **options)

    def pool_grow(self, method, n=1, **kwargs):
        """[N=1]"""
        return self.call(method, int(n), **kwargs)

    def pool_shrink(self, method, n=1, **kwargs):
        """[N=1]"""
        return self.call(method, int(n), **kwargs)

    def autoscale(self, method, max=None, min=None, **kwargs):
        """[max] [min]"""
        return self.call(method, int(max), int(min), **kwargs)

    def rate_limit(self, method, task_name, rate_limit, **kwargs):
        """<task_name> <rate_limit> (e.g. 5/s | 5/m | 5/h)>"""
        return self.call(method, task_name, rate_limit, **kwargs)

    def time_limit(self, method, task_name, soft, hard=None, **kwargs):
        """<task_name> <soft_secs> [hard_secs]"""
        return self.call(method, task_name,
                         float(soft), float(hard), **kwargs)

    def add_consumer(self, method, queue, exchange=None,
                     exchange_type='direct', routing_key=None, **kwargs):
        """<queue> [exchange [type [routing_key]]]"""
        return self.call(method, queue, exchange,
                         exchange_type, routing_key, **kwargs)

    def cancel_consumer(self, method, queue, **kwargs):
        """<queue>"""
        return self.call(method, queue, **kwargs)


class status(Command):
    """Show list of workers that are online."""
    option_list = inspect.option_list

    def run(self, *args, **kwargs):
        I = inspect(
            app=self.app,
            no_color=kwargs.get('no_color', False),
            stdout=self.stdout, stderr=self.stderr,
            show_reply=False, show_body=False, quiet=True,
        )
        replies = I.run('ping', **kwargs)
        if not replies:
            raise self.Error('No nodes replied within time constraint',
                             status=EX_UNAVAILABLE)
        nodecount = len(replies)
        if not kwargs.get('quiet', False):
            self.out('\n{0} {1} online.'.format(
                nodecount, text.pluralize(nodecount, 'node')))


class migrate(Command):
    """Migrate tasks from one broker to another.

    Examples::

        celery migrate redis://localhost amqp://guest@localhost//
        celery migrate django:// redis://localhost

    NOTE: This command is experimental, make sure you have
          a backup of the tasks before you continue.
    """
    args = '<source_url> <dest_url>'
    option_list = Command.option_list + (
        Option('--limit', '-n', type='int',
               help='Number of tasks to consume (int)'),
        Option('--timeout', '-t', type='float', default=1.0,
               help='Timeout in seconds (float) waiting for tasks'),
        Option('--ack-messages', '-a', action='store_true',
               help='Ack messages from source broker.'),
        Option('--tasks', '-T',
               help='List of task names to filter on.'),
        Option('--queues', '-Q',
               help='List of queues to migrate.'),
        Option('--forever', '-F', action='store_true',
               help='Continually migrate tasks until killed.'),
    )
    progress_fmt = MIGRATE_PROGRESS_FMT

    def on_migrate_task(self, state, body, message):
        self.out(self.progress_fmt.format(state=state, body=body))

    def run(self, source, destination, **kwargs):
        from kombu import Connection
        from celery.contrib.migrate import migrate_tasks

        migrate_tasks(Connection(source),
                      Connection(destination),
                      callback=self.on_migrate_task,
                      **kwargs)


class shell(Command):  # pragma: no cover
    """Start shell session with convenient access to celery symbols.

    The following symbols will be added to the main globals:

        - celery:  the current application.
        - chord, group, chain, chunks,
          xmap, xstarmap subtask, Task
        - all registered tasks.

    """
    option_list = Command.option_list + (
        Option('--ipython', '-I',
               action='store_true', dest='force_ipython',
               help='force iPython.'),
        Option('--bpython', '-B',
               action='store_true', dest='force_bpython',
               help='force bpython.'),
        Option('--python', '-P',
               action='store_true', dest='force_python',
               help='force default Python shell.'),
        Option('--without-tasks', '-T', action='store_true',
               help="don't add tasks to locals."),
        Option('--eventlet', action='store_true',
               help='use eventlet.'),
        Option('--gevent', action='store_true', help='use gevent.'),
    )

    def run(self, force_ipython=False, force_bpython=False,
            force_python=False, without_tasks=False, eventlet=False,
            gevent=False, **kwargs):
        sys.path.insert(0, os.getcwd())
        if eventlet:
            import_module('celery.concurrency.eventlet')
        if gevent:
            import_module('celery.concurrency.gevent')
        import celery
        import celery.task.base
        self.app.loader.import_default_modules()
        self.locals = {'app': self.app,
                       'celery': self.app,
                       'Task': celery.Task,
                       'chord': celery.chord,
                       'group': celery.group,
                       'chain': celery.chain,
                       'chunks': celery.chunks,
                       'xmap': celery.xmap,
                       'xstarmap': celery.xstarmap,
                       'subtask': celery.subtask,
                       'signature': celery.signature}

        if not without_tasks:
            self.locals.update(dict(
                (task.__name__, task) for task in values(self.app.tasks)
                if not task.name.startswith('celery.')),
            )

        if force_python:
            return self.invoke_fallback_shell()
        elif force_bpython:
            return self.invoke_bpython_shell()
        elif force_ipython:
            return self.invoke_ipython_shell()
        return self.invoke_default_shell()

    def invoke_default_shell(self):
        try:
            import IPython  # noqa
        except ImportError:
            try:
                import bpython  # noqa
            except ImportError:
                return self.invoke_fallback_shell()
            else:
                return self.invoke_bpython_shell()
        else:
            return self.invoke_ipython_shell()

    def invoke_fallback_shell(self):
        import code
        try:
            import readline
        except ImportError:
            pass
        else:
            import rlcompleter
            readline.set_completer(
                rlcompleter.Completer(self.locals).complete)
            readline.parse_and_bind('tab:complete')
        code.interact(local=self.locals)

    def invoke_ipython_shell(self):
        try:
            from IPython.terminal import embed
            embed.TerminalInteractiveShell(user_ns=self.locals).mainloop()
        except ImportError:  # ipython < 0.11
            from IPython.Shell import IPShell
            IPShell(argv=[], user_ns=self.locals).mainloop()

    def invoke_bpython_shell(self):
        import bpython
        bpython.embed(self.locals)


class help(Command):
    """Show help screen and exit."""

    def usage(self, command):
        return '%prog <command> [options] {0.args}'.format(self)

    def run(self, *args, **kwargs):
        self.parser.print_help()
        self.out(HELP.format(
            prog_name=self.prog_name,
            commands=CeleryCommand.list_commands(colored=self.colored),
        ))

        return EX_USAGE


class report(Command):
    """Shows information useful to include in bugreports."""

    def run(self, *args, **kwargs):
        self.out(self.app.bugreport())
        return EX_OK


class CeleryCommand(Command):
    namespace = 'celery'
    ext_fmt = '{self.namespace}.commands'
    commands = {
        'amqp': amqp,
        'beat': beat,
        'call': call,
        'control': control,
        'events': events,
        'graph': graph,
        'help': help,
        'inspect': inspect,
        'list': list_,
        'migrate': migrate,
        'multi': multi,
        'purge': purge,
        'report': report,
        'result': result,
        'shell': shell,
        'status': status,
        'worker': worker,

    }
    enable_config_from_cmdline = True
    prog_name = 'celery'

    @classmethod
    def register_command(cls, fun, name=None):
        cls.commands[name or fun.__name__] = fun
        return fun

    def execute(self, command, argv=None):
        try:
            cls = self.commands[command]
        except KeyError:
            cls, argv = self.commands['help'], ['help']
        cls = self.commands.get(command) or self.commands['help']
        try:
            return cls(
                app=self.app, on_error=self.on_error,
                no_color=self.no_color, quiet=self.quiet,
                on_usage_error=partial(self.on_usage_error, command=command),
            ).run_from_argv(self.prog_name, argv[1:], command=argv[0])
        except self.UsageError as exc:
            self.on_usage_error(exc)
            return exc.status
        except self.Error as exc:
            self.on_error(exc)
            return exc.status

    def on_usage_error(self, exc, command=None):
        if command:
            helps = '{self.prog_name} {command} --help'
        else:
            helps = '{self.prog_name} --help'
        self.error(self.colored.magenta('Error: {0}'.format(exc)))
        self.error("""Please try '{0}'""".format(helps.format(
            self=self, command=command,
        )))

    def _relocate_args_from_start(self, argv, index=0):
        if argv:
            rest = []
            while index < len(argv):
                value = argv[index]
                if value.startswith('--'):
                    rest.append(value)
                elif value.startswith('-'):
                    # we eat the next argument even though we don't know
                    # if this option takes an argument or not.
                    # instead we will assume what is the command name in the
                    # return statements below.
                    try:
                        nxt = argv[index + 1]
                        if nxt.startswith('-'):
                            # is another option
                            rest.append(value)
                        else:
                            # is (maybe) a value for this option
                            rest.extend([value, nxt])
                            index += 1
                    except IndexError:
                        rest.append(value)
                        break
                else:
                    break
                index += 1
            if argv[index:]:
                # if there are more arguments left then divide and swap
                # we assume the first argument in argv[i:] is the command
                # name.
                return argv[index:] + rest
            # if there are no more arguments then the last arg in rest'
            # must be the command.
            [rest.pop()] + rest
        return []

    def prepare_prog_name(self, name):
        if name == '__main__.py':
            return sys.modules['__main__'].__file__
        return name

    def handle_argv(self, prog_name, argv):
        self.prog_name = self.prepare_prog_name(prog_name)
        argv = self._relocate_args_from_start(argv)
        _, argv = self.prepare_args(None, argv)
        try:
            command = argv[0]
        except IndexError:
            command, argv = 'help', ['help']
        return self.execute(command, argv)

    def execute_from_commandline(self, argv=None):
        argv = sys.argv if argv is None else argv
        if 'multi' in argv[1:3]:  # Issue 1008
            self.respects_app_option = False
        try:
            sys.exit(determine_exit_status(
                super(CeleryCommand, self).execute_from_commandline(argv)))
        except KeyboardInterrupt:
            sys.exit(EX_FAILURE)

    @classmethod
    def get_command_info(self, command, indent=0, color=None, colored=None):
        colored = term.colored() if colored is None else colored
        colored = colored.names[color] if color else lambda x: x
        obj = self.commands[command]
        cmd = 'celery {0}'.format(colored(command))
        if obj.leaf:
            return '|' + text.indent(cmd, indent)
        return text.join([
            ' ',
            '|' + text.indent('{0} --help'.format(cmd), indent),
            obj.list_commands(indent, 'celery {0}'.format(command), colored),
        ])

    @classmethod
    def list_commands(self, indent=0, colored=None):
        colored = term.colored() if colored is None else colored
        white = colored.white
        ret = []
        for cls, commands, color in command_classes:
            ret.extend([
                text.indent('+ {0}: '.format(white(cls)), indent),
                '\n'.join(
                    self.get_command_info(command, indent + 4, color, colored)
                    for command in commands),
                ''
            ])
        return '\n'.join(ret).strip()

    def with_pool_option(self, argv):
        if len(argv) > 1 and 'worker' in argv[0:3]:
            # this command supports custom pools
            # that may have to be loaded as early as possible.
            return (['-P'], ['--pool'])

    def on_concurrency_setup(self):
        self.load_extension_commands()

    def load_extension_commands(self):
        names = Extensions(self.ext_fmt.format(self=self),
                           self.register_command).load()
        if names:
            command_classes.append(('Extensions', names, 'magenta'))


def command(*args, **kwargs):
    """Deprecated: Use classmethod :meth:`CeleryCommand.register_command`
    instead."""
    _register = CeleryCommand.register_command
    return _register(args[0]) if args else _register


if __name__ == '__main__':          # pragma: no cover
    main()