IPython/kernel/client.py

#!/usr/bin/env python
# encoding: utf-8

"""This module contains blocking clients for the controller interfaces.

Unlike the clients in `asyncclient.py`, the clients in this module are fully
blocking.  This means that methods on the clients return the actual results
rather than a deferred to the result.  Also, we manage the Twisted reactor
for you.  This is done by running the reactor in a thread.

The main classes in this module are:

    * MultiEngineClient
    * TaskClient
    * Task
    * CompositeError
"""

#-----------------------------------------------------------------------------
#  Copyright (C) 2008-2009  The IPython Development Team
#
#  Distributed under the terms of the BSD License.  The full license is in
#  the file COPYING, distributed as part of this software.
#-----------------------------------------------------------------------------

#-----------------------------------------------------------------------------
# Warnings control
#-----------------------------------------------------------------------------

import warnings

# Twisted generates annoying warnings with Python 2.6, as will do other code
# that imports 'sets' as of today
warnings.filterwarnings('ignore', 'the sets module is deprecated',
                        DeprecationWarning )

# This one also comes from Twisted
warnings.filterwarnings('ignore', 'the sha module is deprecated',
                        DeprecationWarning)

#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------

import sys

import twisted
from twisted.internet import reactor
from twisted.python import log

from IPython.kernel.clientconnector import ClientConnector, Cluster
from IPython.kernel.twistedutil import ReactorInThread
from IPython.kernel.twistedutil import blockingCallFromThread

# These enable various things 
from IPython.kernel import codeutil

# Other things that the user will need
from IPython.kernel.task import MapTask, StringTask
from IPython.kernel.error import CompositeError

#-------------------------------------------------------------------------------
# Code
#-------------------------------------------------------------------------------

# PotentialZombieWarning is deprecated from Twisted 10.0.0 and above and
# using the filter on > 10.0.0 creates a warning itself.
if twisted.version.major < 10:
    from twisted.internet.error import PotentialZombieWarning
    warnings.simplefilter('ignore', PotentialZombieWarning)

_client_tub = ClientConnector()

get_multiengine_client = _client_tub.get_multiengine_client
get_task_client = _client_tub.get_task_client
MultiEngineClient = get_multiengine_client
TaskClient = get_task_client

# This isn't great.  I should probably set this up in the ReactorInThread
# class below.  But, it does work for now.
log.startLogging(sys.stdout, setStdout=0)

def _result_list_printer(obj, p, cycle):
    if cycle:
        return p.text('ResultList(...)')
    return p.text(repr(obj))

# ResultList is a list subclass and will use the default pretty printer.
# This overrides that to use the __repr__ of ResultList.
ip = get_ipython()
ip.display_formatter.formatters['text/plain'].for_type_by_name(
    'IPython.kernel.multiengineclient', 'ResultList', _result_list_printer
)

# Now we start the reactor in a thread
rit = ReactorInThread()
rit.setDaemon(True)
rit.start()


__all__ = [
    'MapTask',
    'StringTask',
    'MultiEngineClient',
    'TaskClient',
    'CompositeError',
    'get_task_client',
    'get_multiengine_client',
    'Cluster'
]