pyzmq-2.1.3 related testing adjustments

IPython/zmq/parallel/__init__.py

@@ -1,18 +1,23 b''
 """The IPython ZMQ-based parallel computing interface."""
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2011 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.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # from .asyncresult import *
 # from .client import Client
 # from .dependency import *
 # from .remotefunction import *
 # from .view import *
 
+import zmq
+
+if zmq.__version__ < '2.1.3':
+    raise ImportError("IPython.zmq.parallel requires pyzmq/0MQ >= 2.1.3, you appear to have %s"%zmq.__version__)
+

IPython/zmq/parallel/client.py

@@ -1,1584 +1,1591 b''
 """A semi-synchronous Client for the ZMQ controller"""
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2010  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.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import os
 import json
 import time
 import warnings
 from datetime import datetime
 from getpass import getpass
 from pprint import pprint
 
 pjoin = os.path.join
 
 import zmq
 # from zmq.eventloop import ioloop, zmqstream
 
 from IPython.utils.path import get_ipython_dir
 from IPython.utils.pickleutil import Reference
 from IPython.utils.traitlets import (HasTraits, Int, Instance, CUnicode, 
                                     Dict, List, Bool, Str, Set)
 from IPython.external.decorator import decorator
 from IPython.external.ssh import tunnel
 
 from . import error
 from . import map as Map
 from . import util
 from . import streamsession as ss
 from .asyncresult import AsyncResult, AsyncMapResult, AsyncHubResult
 from .clusterdir import ClusterDir, ClusterDirError
 from .dependency import Dependency, depend, require, dependent
 from .remotefunction import remote, parallel, ParallelFunction, RemoteFunction
 from .util import ReverseDict, validate_url, disambiguate_url
 from .view import DirectView, LoadBalancedView
 
 #--------------------------------------------------------------------------
 # helpers for implementing old MEC API via client.apply
 #--------------------------------------------------------------------------
 
 def _push(user_ns, **ns):
     """helper method for implementing `client.push` via `client.apply`"""
     user_ns.update(ns)
 
 def _pull(user_ns, keys):
     """helper method for implementing `client.pull` via `client.apply`"""
     if isinstance(keys, (list,tuple, set)):
         for key in keys:
             if not user_ns.has_key(key):
                 raise NameError("name '%s' is not defined"%key)
         return map(user_ns.get, keys)
     else:
         if not user_ns.has_key(keys):
             raise NameError("name '%s' is not defined"%keys)
         return user_ns.get(keys)
 
 def _clear(user_ns):
     """helper method for implementing `client.clear` via `client.apply`"""
     user_ns.clear()
 
 def _execute(user_ns, code):
     """helper method for implementing `client.execute` via `client.apply`"""
     exec code in user_ns
     
 
 #--------------------------------------------------------------------------
 # Decorators for Client methods
 #--------------------------------------------------------------------------
 
 @decorator
 def spinfirst(f, self, *args, **kwargs):
     """Call spin() to sync state prior to calling the method."""
     self.spin()
     return f(self, *args, **kwargs)
 
 @decorator
 def defaultblock(f, self, *args, **kwargs):
     """Default to self.block; preserve self.block."""
     block = kwargs.get('block',None)
     block = self.block if block is None else block
     saveblock = self.block
     self.block = block
     try:
         ret = f(self, *args, **kwargs)
     finally:
         self.block = saveblock
     return ret
 
 
 #--------------------------------------------------------------------------
 # Classes
 #--------------------------------------------------------------------------
 
 class Metadata(dict):
     """Subclass of dict for initializing metadata values.
     
     Attribute access works on keys.
     
     These objects have a strict set of keys - errors will raise if you try
     to add new keys.
     """
     def __init__(self, *args, **kwargs):
         dict.__init__(self)
         md = {'msg_id' : None,
               'submitted' : None,
               'started' : None,
               'completed' : None,
               'received' : None,
               'engine_uuid' : None,
               'engine_id' : None,
               'follow' : None,
               'after' : None,
               'status' : None,
 
               'pyin' : None,
               'pyout' : None,
               'pyerr' : None,
               'stdout' : '',
               'stderr' : '',
             }
         self.update(md)
         self.update(dict(*args, **kwargs))
     
     def __getattr__(self, key):
         """getattr aliased to getitem"""
         if key in self.iterkeys():
             return self[key]
         else:
             raise AttributeError(key)
 
     def __setattr__(self, key, value):
         """setattr aliased to setitem, with strict"""
         if key in self.iterkeys():
             self[key] = value
         else:
             raise AttributeError(key)
     
     def __setitem__(self, key, value):
         """strict static key enforcement"""
         if key in self.iterkeys():
             dict.__setitem__(self, key, value)
         else:
             raise KeyError(key)
         
 
 class Client(HasTraits):
     """A semi-synchronous client to the IPython ZMQ controller
     
     Parameters
     ----------
     
     url_or_file : bytes; zmq url or path to ipcontroller-client.json
         Connection information for the Hub's registration.  If a json connector
         file is given, then likely no further configuration is necessary.
         [Default: use profile]
     profile : bytes
         The name of the Cluster profile to be used to find connector information.
         [Default: 'default']
     context : zmq.Context
         Pass an existing zmq.Context instance, otherwise the client will create its own.
     username : bytes
         set username to be passed to the Session object
     debug : bool
         flag for lots of message printing for debug purposes
  
     #-------------- ssh related args ----------------
     # These are args for configuring the ssh tunnel to be used
     # credentials are used to forward connections over ssh to the Controller
     # Note that the ip given in `addr` needs to be relative to sshserver
     # The most basic case is to leave addr as pointing to localhost (127.0.0.1),
     # and set sshserver as the same machine the Controller is on. However, 
     # the only requirement is that sshserver is able to see the Controller
     # (i.e. is within the same trusted network).
     
     sshserver : str
         A string of the form passed to ssh, i.e. 'server.tld' or '[e-mail]:port'
         If keyfile or password is specified, and this is not, it will default to
         the ip given in addr.
     sshkey : str; path to public ssh key file
         This specifies a key to be used in ssh login, default None.
         Regular default ssh keys will be used without specifying this argument.
     password : str 
         Your ssh password to sshserver. Note that if this is left None,
         you will be prompted for it if passwordless key based login is unavailable.
     paramiko : bool
         flag for whether to use paramiko instead of shell ssh for tunneling.
         [default: True on win32, False else]
     
     #------- exec authentication args -------
     # If even localhost is untrusted, you can have some protection against
     # unauthorized execution by using a key.  Messages are still sent
     # as cleartext, so if someone can snoop your loopback traffic this will
     # not help against malicious attacks.
     
     exec_key : str
         an authentication key or file containing a key
         default: None
     
     
     Attributes
     ----------
     
     ids : set of int engine IDs
         requesting the ids attribute always synchronizes
         the registration state. To request ids without synchronization,
         use semi-private _ids attributes.
     
     history : list of msg_ids
         a list of msg_ids, keeping track of all the execution
         messages you have submitted in order.
     
     outstanding : set of msg_ids
         a set of msg_ids that have been submitted, but whose
         results have not yet been received.
     
     results : dict
         a dict of all our results, keyed by msg_id
     
     block : bool
         determines default behavior when block not specified
         in execution methods
     
     Methods
     -------
     
     spin
         flushes incoming results and registration state changes
         control methods spin, and requesting `ids` also ensures up to date
     
     barrier
         wait on one or more msg_ids
     
     execution methods
         apply
         legacy: execute, run
     
     query methods
         queue_status, get_result, purge
     
     control methods
         abort, shutdown
     
     """
     
     
     block = Bool(False)
     outstanding = Set()
     results = Instance('collections.defaultdict', (dict,))
     metadata = Instance('collections.defaultdict', (Metadata,))
     history = List()
     debug = Bool(False)
     profile=CUnicode('default')
     
     _outstanding_dict = Instance('collections.defaultdict', (set,))
     _ids = List()
     _connected=Bool(False)
     _ssh=Bool(False)
     _context = Instance('zmq.Context')
     _config = Dict()
     _engines=Instance(ReverseDict, (), {})
     # _hub_socket=Instance('zmq.Socket')
     _query_socket=Instance('zmq.Socket')
     _control_socket=Instance('zmq.Socket')
     _iopub_socket=Instance('zmq.Socket')
     _notification_socket=Instance('zmq.Socket')
     _apply_socket=Instance('zmq.Socket')
     _mux_ident=Str()
     _task_ident=Str()
     _task_scheme=Str()
     _balanced_views=Dict()
     _direct_views=Dict()
     _closed = False
     
     def __init__(self, url_or_file=None, profile='default', cluster_dir=None, ipython_dir=None,
             context=None, username=None, debug=False, exec_key=None,
             sshserver=None, sshkey=None, password=None, paramiko=None,
             ):
         super(Client, self).__init__(debug=debug, profile=profile)
         if context is None:
-            context = zmq.Context()
+            context = zmq.Context.instance()
         self._context = context
             
         
         self._setup_cluster_dir(profile, cluster_dir, ipython_dir)
         if self._cd is not None:
             if url_or_file is None:
                 url_or_file = pjoin(self._cd.security_dir, 'ipcontroller-client.json')
         assert url_or_file is not None, "I can't find enough information to connect to a controller!"\
             " Please specify at least one of url_or_file or profile."
         
         try:
             validate_url(url_or_file)
         except AssertionError:
             if not os.path.exists(url_or_file):
                 if self._cd:
                     url_or_file = os.path.join(self._cd.security_dir, url_or_file)
                 assert os.path.exists(url_or_file), "Not a valid connection file or url: %r"%url_or_file
             with open(url_or_file) as f:
                 cfg = json.loads(f.read())
         else:
             cfg = {'url':url_or_file}
         
         # sync defaults from args, json:
         if sshserver:
             cfg['ssh'] = sshserver
         if exec_key:
             cfg['exec_key'] = exec_key
         exec_key = cfg['exec_key']
         sshserver=cfg['ssh']
         url = cfg['url']
         location = cfg.setdefault('location', None)
         cfg['url'] = disambiguate_url(cfg['url'], location)
         url = cfg['url']
         
         self._config = cfg
         
         self._ssh = bool(sshserver or sshkey or password)
         if self._ssh and sshserver is None:
             # default to ssh via localhost
             sshserver = url.split('://')[1].split(':')[0]
         if self._ssh and password is None:
             if tunnel.try_passwordless_ssh(sshserver, sshkey, paramiko):
                 password=False
             else:
                 password = getpass("SSH Password for %s: "%sshserver)
         ssh_kwargs = dict(keyfile=sshkey, password=password, paramiko=paramiko)
         if exec_key is not None and os.path.isfile(exec_key):
             arg = 'keyfile'
         else:
             arg = 'key'
         key_arg = {arg:exec_key}
         if username is None:
             self.session = ss.StreamSession(**key_arg)
         else:
             self.session = ss.StreamSession(username, **key_arg)
         self._query_socket = self._context.socket(zmq.XREQ)
         self._query_socket.setsockopt(zmq.IDENTITY, self.session.session)
         if self._ssh:
             tunnel.tunnel_connection(self._query_socket, url, sshserver, **ssh_kwargs)
         else:
             self._query_socket.connect(url)
         
         self.session.debug = self.debug
         
         self._notification_handlers = {'registration_notification' : self._register_engine,
                                     'unregistration_notification' : self._unregister_engine,
                                     }
         self._queue_handlers = {'execute_reply' : self._handle_execute_reply,
                                 'apply_reply' : self._handle_apply_reply}
         self._connect(sshserver, ssh_kwargs)
         
     def __del__(self):
         """cleanup sockets, but _not_ context."""
         self.close()
     
     def _setup_cluster_dir(self, profile, cluster_dir, ipython_dir):
         if ipython_dir is None:
             ipython_dir = get_ipython_dir()
         if cluster_dir is not None:
             try:
                 self._cd = ClusterDir.find_cluster_dir(cluster_dir)
                 return
             except ClusterDirError:
                 pass
         elif profile is not None:
             try:
                 self._cd = ClusterDir.find_cluster_dir_by_profile(
                     ipython_dir, profile)
                 return
             except ClusterDirError:
                 pass
         self._cd = None
     
     @property
     def ids(self):
         """Always up-to-date ids property."""
         self._flush_notifications()
         # always copy:
         return list(self._ids)
         
     def close(self):
         if self._closed:
             return
         snames = filter(lambda n: n.endswith('socket'), dir(self))
         for socket in map(lambda name: getattr(self, name), snames):
             if isinstance(socket, zmq.Socket) and not socket.closed:
                 socket.close()
         self._closed = True
     
     def _update_engines(self, engines):
         """Update our engines dict and _ids from a dict of the form: {id:uuid}."""
         for k,v in engines.iteritems():
             eid = int(k)
             self._engines[eid] = bytes(v) # force not unicode
             self._ids.append(eid)
         self._ids = sorted(self._ids)
         if sorted(self._engines.keys()) != range(len(self._engines)) and \
                         self._task_scheme == 'pure' and self._task_ident:
             self._stop_scheduling_tasks()
     
     def _stop_scheduling_tasks(self):
         """Stop scheduling tasks because an engine has been unregistered
         from a pure ZMQ scheduler.
         """
         self._task_ident = ''
         # self._task_socket.close()
         # self._task_socket = None
         msg = "An engine has been unregistered, and we are using pure " +\
               "ZMQ task scheduling.  Task farming will be disabled."
         if self.outstanding:
             msg += " If you were running tasks when this happened, " +\
                    "some `outstanding` msg_ids may never resolve."
         warnings.warn(msg, RuntimeWarning)
     
     def _build_targets(self, targets):
         """Turn valid target IDs or 'all' into two lists:
         (int_ids, uuids).
         """
         if targets is None:
             targets = self._ids
         elif isinstance(targets, str):
             if targets.lower() == 'all':
                 targets = self._ids
             else:
                 raise TypeError("%r not valid str target, must be 'all'"%(targets))
         elif isinstance(targets, int):
             targets = [targets]
         return [self._engines[t] for t in targets], list(targets)
     
     def _connect(self, sshserver, ssh_kwargs):
         """setup all our socket connections to the controller. This is called from
         __init__."""
         
         # Maybe allow reconnecting?
         if self._connected:
             return
         self._connected=True
 
         def connect_socket(s, url):
             url = disambiguate_url(url, self._config['location'])
             if self._ssh:
                 return tunnel.tunnel_connection(s, url, sshserver, **ssh_kwargs)
             else:
                 return s.connect(url)
             
         self.session.send(self._query_socket, 'connection_request')
         idents,msg = self.session.recv(self._query_socket,mode=0)
         if self.debug:
             pprint(msg)
         msg = ss.Message(msg)
         content = msg.content
         self._config['registration'] = dict(content)
         if content.status == 'ok':
             self._apply_socket = self._context.socket(zmq.XREP)
             self._apply_socket.setsockopt(zmq.IDENTITY, self.session.session)
             if content.mux:
                 # self._mux_socket = self._context.socket(zmq.XREQ)
                 self._mux_ident = 'mux'
                 connect_socket(self._apply_socket, content.mux)
             if content.task:
                 self._task_scheme, task_addr = content.task
                 # self._task_socket = self._context.socket(zmq.XREQ)
                 # self._task_socket.setsockopt(zmq.IDENTITY, self.session.session)
                 connect_socket(self._apply_socket, task_addr)
                 self._task_ident = 'task'
             if content.notification:
                 self._notification_socket = self._context.socket(zmq.SUB)
                 connect_socket(self._notification_socket, content.notification)
                 self._notification_socket.setsockopt(zmq.SUBSCRIBE, b'')
             # if content.query:
             #     self._query_socket = self._context.socket(zmq.XREQ)
             #     self._query_socket.setsockopt(zmq.IDENTITY, self.session.session)
             #     connect_socket(self._query_socket, content.query)
             if content.control:
                 self._control_socket = self._context.socket(zmq.XREQ)
                 self._control_socket.setsockopt(zmq.IDENTITY, self.session.session)
                 connect_socket(self._control_socket, content.control)
             if content.iopub:
                 self._iopub_socket = self._context.socket(zmq.SUB)
                 self._iopub_socket.setsockopt(zmq.SUBSCRIBE, b'')
                 self._iopub_socket.setsockopt(zmq.IDENTITY, self.session.session)
                 connect_socket(self._iopub_socket, content.iopub)
             self._update_engines(dict(content.engines))
             # give XREP apply_socket some time to connect
             time.sleep(0.25)
         else:
             self._connected = False
             raise Exception("Failed to connect!")
     
     #--------------------------------------------------------------------------
     # handlers and callbacks for incoming messages
     #--------------------------------------------------------------------------
     
     def _unwrap_exception(self, content):
         """unwrap exception, and remap engineid to int."""
         e = error.unwrap_exception(content)
         # print e.traceback
         if e.engine_info:
             e_uuid = e.engine_info['engine_uuid']
             eid = self._engines[e_uuid]
             e.engine_info['engine_id'] = eid
         return e
     
     def _extract_metadata(self, header, parent, content):
         md = {'msg_id' : parent['msg_id'],
               'received' : datetime.now(),
               'engine_uuid' : header.get('engine', None),
               'follow' : parent.get('follow', []),
               'after' : parent.get('after', []),
               'status' : content['status'],
             }
         
         if md['engine_uuid'] is not None:
             md['engine_id'] = self._engines.get(md['engine_uuid'], None)
         
         if 'date' in parent:
             md['submitted'] = datetime.strptime(parent['date'], util.ISO8601)
         if 'started' in header:
             md['started'] = datetime.strptime(header['started'], util.ISO8601)
         if 'date' in header:
             md['completed'] = datetime.strptime(header['date'], util.ISO8601)
         return md
     
     def _register_engine(self, msg):
         """Register a new engine, and update our connection info."""
         content = msg['content']
         eid = content['id']
         d = {eid : content['queue']}
         self._update_engines(d)
 
     def _unregister_engine(self, msg):
         """Unregister an engine that has died."""
         content = msg['content']
         eid = int(content['id'])
         if eid in self._ids:
             self._ids.remove(eid)
             uuid = self._engines.pop(eid)
             
             self._handle_stranded_msgs(eid, uuid)
                 
         if self._task_ident and self._task_scheme == 'pure':
             self._stop_scheduling_tasks()
     
     def _handle_stranded_msgs(self, eid, uuid):
         """Handle messages known to be on an engine when the engine unregisters.
         
         It is possible that this will fire prematurely - that is, an engine will
         go down after completing a result, and the client will be notified
         of the unregistration and later receive the successful result.
         """
         
         outstanding = self._outstanding_dict[uuid]
         
         for msg_id in list(outstanding):
             if msg_id in self.results:
                 # we already 
                 continue
             try:
                 raise error.EngineError("Engine %r died while running task %r"%(eid, msg_id))
             except:
                 content = error.wrap_exception()
             # build a fake message:
             parent = {}
             header = {}
             parent['msg_id'] = msg_id
             header['engine'] = uuid
             header['date'] = datetime.now().strftime(util.ISO8601)
             msg = dict(parent_header=parent, header=header, content=content)
             self._handle_apply_reply(msg)
     
     def _handle_execute_reply(self, msg):
         """Save the reply to an execute_request into our results.
         
         execute messages are never actually used. apply is used instead.
         """
         
         parent = msg['parent_header']
         msg_id = parent['msg_id']
         if msg_id not in self.outstanding:
             if msg_id in self.history:
                 print ("got stale result: %s"%msg_id)
             else:
                 print ("got unknown result: %s"%msg_id)
         else:
             self.outstanding.remove(msg_id)
         self.results[msg_id] = self._unwrap_exception(msg['content'])
     
     def _handle_apply_reply(self, msg):
         """Save the reply to an apply_request into our results."""
         parent = msg['parent_header']
         msg_id = parent['msg_id']
         if msg_id not in self.outstanding:
             if msg_id in self.history:
                 print ("got stale result: %s"%msg_id)
                 print self.results[msg_id]
                 print msg
             else:
                 print ("got unknown result: %s"%msg_id)
         else:
             self.outstanding.remove(msg_id)
         content = msg['content']
         header = msg['header']
         
         # construct metadata:
         md = self.metadata[msg_id]
         md.update(self._extract_metadata(header, parent, content))
         # is this redundant?
         self.metadata[msg_id] = md
         
         e_outstanding = self._outstanding_dict[md['engine_uuid']]
         if msg_id in e_outstanding:
             e_outstanding.remove(msg_id)
         
         # construct result:
         if content['status'] == 'ok':
             self.results[msg_id] = util.unserialize_object(msg['buffers'])[0]
         elif content['status'] == 'aborted':
             self.results[msg_id] = error.AbortedTask(msg_id)
         elif content['status'] == 'resubmitted':
             # TODO: handle resubmission
             pass
         else:
             self.results[msg_id] = self._unwrap_exception(content)
     
     def _flush_notifications(self):
         """Flush notifications of engine registrations waiting
         in ZMQ queue."""
         msg = self.session.recv(self._notification_socket, mode=zmq.NOBLOCK)
         while msg is not None:
             if self.debug:
                 pprint(msg)
             msg = msg[-1]
             msg_type = msg['msg_type']
             handler = self._notification_handlers.get(msg_type, None)
             if handler is None:
                 raise Exception("Unhandled message type: %s"%msg.msg_type)
             else:
                 handler(msg)
             msg = self.session.recv(self._notification_socket, mode=zmq.NOBLOCK)
     
     def _flush_results(self, sock):
         """Flush task or queue results waiting in ZMQ queue."""
         msg = self.session.recv(sock, mode=zmq.NOBLOCK)
         while msg is not None:
             if self.debug:
                 pprint(msg)
             msg = msg[-1]
             msg_type = msg['msg_type']
             handler = self._queue_handlers.get(msg_type, None)
             if handler is None:
                 raise Exception("Unhandled message type: %s"%msg.msg_type)
             else:
                 handler(msg)
             msg = self.session.recv(sock, mode=zmq.NOBLOCK)
     
     def _flush_control(self, sock):
         """Flush replies from the control channel waiting
         in the ZMQ queue.
         
         Currently: ignore them."""
         msg = self.session.recv(sock, mode=zmq.NOBLOCK)
         while msg is not None:
             if self.debug:
                 pprint(msg)
             msg = self.session.recv(sock, mode=zmq.NOBLOCK)
     
     def _flush_iopub(self, sock):
         """Flush replies from the iopub channel waiting
         in the ZMQ queue.
         """
         msg = self.session.recv(sock, mode=zmq.NOBLOCK)
         while msg is not None:
             if self.debug:
                 pprint(msg)
             msg = msg[-1]
             parent = msg['parent_header']
             msg_id = parent['msg_id']
             content = msg['content']
             header = msg['header']
             msg_type = msg['msg_type']
             
             # init metadata:
             md = self.metadata[msg_id]
             
             if msg_type == 'stream':
                 name = content['name']
                 s = md[name] or ''
                 md[name] = s + content['data']
             elif msg_type == 'pyerr':
                 md.update({'pyerr' : self._unwrap_exception(content)})
             else:
                 md.update({msg_type : content['data']})
             
             # reduntant?
             self.metadata[msg_id] = md
             
             msg = self.session.recv(sock, mode=zmq.NOBLOCK)
     
     #--------------------------------------------------------------------------
     # len, getitem
     #--------------------------------------------------------------------------
     
     def __len__(self):
         """len(client) returns # of engines."""
         return len(self.ids)
     
     def __getitem__(self, key):
         """index access returns DirectView multiplexer objects
         
         Must be int, slice, or list/tuple/xrange of ints"""
         if not isinstance(key, (int, slice, tuple, list, xrange)):
             raise TypeError("key by int/slice/iterable of ints only, not %s"%(type(key)))
         else:
             return self.view(key, balanced=False)
     
     #--------------------------------------------------------------------------
     # Begin public methods
     #--------------------------------------------------------------------------
     
     def spin(self):
         """Flush any registration notifications and execution results
         waiting in the ZMQ queue.
         """
         if self._notification_socket:
             self._flush_notifications()
         if self._apply_socket:
             self._flush_results(self._apply_socket)
         if self._control_socket:
             self._flush_control(self._control_socket)
         if self._iopub_socket:
             self._flush_iopub(self._iopub_socket)
     
     def barrier(self, jobs=None, timeout=-1):
         """waits on one or more `jobs`, for up to `timeout` seconds.
         
         Parameters
         ----------
         
         jobs : int, str, or list of ints and/or strs, or one or more AsyncResult objects
                 ints are indices to self.history
                 strs are msg_ids
                 default: wait on all outstanding messages
         timeout : float
                 a time in seconds, after which to give up.
                 default is -1, which means no timeout
         
         Returns
         -------
         
         True : when all msg_ids are done
         False : timeout reached, some msg_ids still outstanding
         """
         tic = time.time()
         if jobs is None:
             theids = self.outstanding
         else:
             if isinstance(jobs, (int, str, AsyncResult)):
                 jobs = [jobs]
             theids = set()
             for job in jobs:
                 if isinstance(job, int):
                     # index access
                     job = self.history[job]
                 elif isinstance(job, AsyncResult):
                     map(theids.add, job.msg_ids)
                     continue
                 theids.add(job)
         if not theids.intersection(self.outstanding):
             return True
         self.spin()
         while theids.intersection(self.outstanding):
             if timeout >= 0 and ( time.time()-tic ) > timeout:
                 break
             time.sleep(1e-3)
             self.spin()
         return len(theids.intersection(self.outstanding)) == 0
     
     #--------------------------------------------------------------------------
     # Control methods
     #--------------------------------------------------------------------------
     
     @spinfirst
     @defaultblock
     def clear(self, targets=None, block=None):
         """Clear the namespace in target(s)."""
         targets = self._build_targets(targets)[0]
         for t in targets:
             self.session.send(self._control_socket, 'clear_request', content={}, ident=t)
         error = False
         if self.block:
             for i in range(len(targets)):
                 idents,msg = self.session.recv(self._control_socket,0)
                 if self.debug:
                     pprint(msg)
                 if msg['content']['status'] != 'ok':
                     error = self._unwrap_exception(msg['content'])
         if error:
             raise error
         
     
     @spinfirst
     @defaultblock
     def abort(self, jobs=None, targets=None, block=None):
         """Abort specific jobs from the execution queues of target(s).
         
         This is a mechanism to prevent jobs that have already been submitted
         from executing.
         
         Parameters
         ----------
         
         jobs : msg_id, list of msg_ids, or AsyncResult
             The jobs to be aborted
         
         
         """
         targets = self._build_targets(targets)[0]
         msg_ids = []
         if isinstance(jobs, (basestring,AsyncResult)):
             jobs = [jobs]
         bad_ids = filter(lambda obj: not isinstance(obj, (basestring, AsyncResult)), jobs)
         if bad_ids:
             raise TypeError("Invalid msg_id type %r, expected str or AsyncResult"%bad_ids[0])
         for j in jobs:
             if isinstance(j, AsyncResult):
                 msg_ids.extend(j.msg_ids)
             else:
                 msg_ids.append(j)
         content = dict(msg_ids=msg_ids)
         for t in targets:
             self.session.send(self._control_socket, 'abort_request', 
                     content=content, ident=t)
         error = False
         if self.block:
             for i in range(len(targets)):
                 idents,msg = self.session.recv(self._control_socket,0)
                 if self.debug:
                     pprint(msg)
                 if msg['content']['status'] != 'ok':
                     error = self._unwrap_exception(msg['content'])
         if error:
             raise error
     
     @spinfirst
     @defaultblock
     def shutdown(self, targets=None, restart=False, controller=False, block=None):
         """Terminates one or more engine processes, optionally including the controller."""
         if controller:
             targets = 'all'
         targets = self._build_targets(targets)[0]
         for t in targets:
             self.session.send(self._control_socket, 'shutdown_request', 
                         content={'restart':restart},ident=t)
         error = False
         if block or controller:
             for i in range(len(targets)):
                 idents,msg = self.session.recv(self._control_socket,0)
                 if self.debug:
                     pprint(msg)
                 if msg['content']['status'] != 'ok':
                     error = self._unwrap_exception(msg['content'])
         
         if controller:
             time.sleep(0.25)
             self.session.send(self._query_socket, 'shutdown_request')
             idents,msg = self.session.recv(self._query_socket, 0)
             if self.debug:
                 pprint(msg)
             if msg['content']['status'] != 'ok':
                 error = self._unwrap_exception(msg['content'])
         
         if error:
             raise error
     
     #--------------------------------------------------------------------------
     # Execution methods
     #--------------------------------------------------------------------------
     
     @defaultblock
     def execute(self, code, targets='all', block=None):
         """Executes `code` on `targets` in blocking or nonblocking manner.
         
         ``execute`` is always `bound` (affects engine namespace)
         
         Parameters
         ----------
         
         code : str
                 the code string to be executed
         targets : int/str/list of ints/strs
                 the engines on which to execute
                 default : all
         block : bool
                 whether or not to wait until done to return
                 default: self.block
         """
         result = self.apply(_execute, (code,), targets=targets, block=block, bound=True, balanced=False)
         if not block:
             return result
     
     def run(self, filename, targets='all', block=None):
         """Execute contents of `filename` on engine(s). 
         
         This simply reads the contents of the file and calls `execute`.
         
         Parameters
         ----------
         
         filename : str
                 The path to the file
         targets : int/str/list of ints/strs
                 the engines on which to execute
                 default : all
         block : bool
                 whether or not to wait until done
                 default: self.block
         
         """
         with open(filename, 'r') as f:
             # add newline in case of trailing indented whitespace
             # which will cause SyntaxError
             code = f.read()+'\n'
         return self.execute(code, targets=targets, block=block)
     
     def _maybe_raise(self, result):
         """wrapper for maybe raising an exception if apply failed."""
         if isinstance(result, error.RemoteError):
             raise result
         
         return result
     
     def _build_dependency(self, dep):
         """helper for building jsonable dependencies from various input forms"""
         if isinstance(dep, Dependency):
             return dep.as_dict()
         elif isinstance(dep, AsyncResult):
             return dep.msg_ids
         elif dep is None:
             return []
         else:
             # pass to Dependency constructor
             return list(Dependency(dep))
         
     @defaultblock
     def apply(self, f, args=None, kwargs=None, bound=False, block=None,
                         targets=None, balanced=None,
                         after=None, follow=None, timeout=None,
                         track=False):
         """Call `f(*args, **kwargs)` on a remote engine(s), returning the result.
         
         This is the central execution command for the client.
         
         Parameters
         ----------
         
         f : function
             The fuction to be called remotely
         args : tuple/list
             The positional arguments passed to `f`
         kwargs : dict
             The keyword arguments passed to `f`
         bound : bool (default: False)
             Whether to pass the Engine(s) Namespace as the first argument to `f`.
         block : bool (default: self.block)
             Whether to wait for the result, or return immediately.
             False:
                 returns AsyncResult
             True:
                 returns actual result(s) of f(*args, **kwargs)
                 if multiple targets:
                     list of results, matching `targets`
+        track : bool
+            whether to track non-copying sends.
+            [default False]
+
         targets : int,list of ints, 'all', None
             Specify the destination of the job.
             if None:
                 Submit via Task queue for load-balancing.
             if 'all':
                 Run on all active engines
             if list:
                 Run on each specified engine
             if int:
                 Run on single engine
-        
+            Note:
+                that if `balanced=True`, and `targets` is specified,
+                then the load-balancing will be limited to balancing
+                among `targets`.
+
         balanced : bool, default None
             whether to load-balance.  This will default to True
             if targets is unspecified, or False if targets is specified.
-            
-            The following arguments are only used when balanced is True:
+
+            If `balanced` and `targets` are both specified, the task will
+            be assigne to *one* of the targets by the scheduler.
+
+        The following arguments are only used when balanced is True:
+
         after : Dependency or collection of msg_ids
             Only for load-balanced execution (targets=None)
             Specify a list of msg_ids as a time-based dependency.
             This job will only be run *after* the dependencies
             have been met.
-            
+
         follow : Dependency or collection of msg_ids
             Only for load-balanced execution (targets=None)
             Specify a list of msg_ids as a location-based dependency.
             This job will only be run on an engine where this dependency
             is met.
-        
+
         timeout : float/int or None
             Only for load-balanced execution (targets=None)
             Specify an amount of time (in seconds) for the scheduler to
             wait for dependencies to be met before failing with a
             DependencyTimeout.
-        track : bool
-            whether to track non-copying sends.
-            [default False]
-        
-        after,follow,timeout only used if `balanced=True`.
         
         Returns
         -------
         
         if block is False:
             return AsyncResult wrapping msg_ids
             output of AsyncResult.get() is identical to that of `apply(...block=True)`
         else:
-            if single target:
+            if single target (or balanced):
                 return result of `f(*args, **kwargs)`
             else:
                 return list of results, matching `targets`
         """
         assert not self._closed, "cannot use me anymore, I'm closed!"
         # defaults:
         block = block if block is not None else self.block
         args = args if args is not None else []
         kwargs = kwargs if kwargs is not None else {}
         
         if not self._ids:
             # flush notification socket if no engines yet
             any_ids = self.ids
             if not any_ids:
                 raise error.NoEnginesRegistered("Can't execute without any connected engines.")
         
         if balanced is None:
             if targets is None:
                 # default to balanced if targets unspecified
                 balanced = True
             else:
                 # otherwise default to multiplexing
                 balanced = False
         
         if targets is None and balanced is False:
             # default to all if *not* balanced, and targets is unspecified
             targets = 'all'
         
         # enforce types of f,args,kwrags
         if not callable(f):
             raise TypeError("f must be callable, not %s"%type(f))
         if not isinstance(args, (tuple, list)):
             raise TypeError("args must be tuple or list, not %s"%type(args))
         if not isinstance(kwargs, dict):
             raise TypeError("kwargs must be dict, not %s"%type(kwargs))
         
         options  = dict(bound=bound, block=block, targets=targets, track=track)
         
         if balanced:
             return self._apply_balanced(f, args, kwargs, timeout=timeout, 
                                         after=after, follow=follow, **options)
         elif follow or after or timeout:
                 msg = "follow, after, and timeout args are only used for"
                 msg += " load-balanced execution."
                 raise ValueError(msg)
         else:
             return self._apply_direct(f, args, kwargs, **options)
     
     def _apply_balanced(self, f, args, kwargs, bound=None, block=None, targets=None,
                             after=None, follow=None, timeout=None, track=None):
         """call f(*args, **kwargs) remotely in a load-balanced manner.
         
         This is a private method, see `apply` for details.
         Not to be called directly!
         """
         
         loc = locals()
         for name in ('bound', 'block', 'track'):
             assert loc[name] is not None, "kwarg %r must be specified!"%name
         
         if not self._task_ident:
             msg = "Task farming is disabled"
             if self._task_scheme == 'pure':
                 msg += " because the pure ZMQ scheduler cannot handle"
                 msg += " disappearing engines."
             raise RuntimeError(msg)
         
         if self._task_scheme == 'pure':
             # pure zmq scheme doesn't support dependencies
             msg = "Pure ZMQ scheduler doesn't support dependencies"
             if (follow or after):
                 # hard fail on DAG dependencies
                 raise RuntimeError(msg)
             if isinstance(f, dependent):
                 # soft warn on functional dependencies
                 warnings.warn(msg, RuntimeWarning)
         
         # defaults:
         args = args if args is not None else []
         kwargs = kwargs if kwargs is not None else {}
         
         if targets:
             idents,_ = self._build_targets(targets)
         else:
             idents = []
         
         after = self._build_dependency(after)
         follow = self._build_dependency(follow)
         subheader = dict(after=after, follow=follow, timeout=timeout, targets=idents)
         bufs = util.pack_apply_message(f,args,kwargs)
         content = dict(bound=bound)
         
         msg = self.session.send(self._apply_socket, "apply_request", ident=self._task_ident,
                 content=content, buffers=bufs, subheader=subheader, track=track)
         msg_id = msg['msg_id']
         self.outstanding.add(msg_id)
         self.history.append(msg_id)
         self.metadata[msg_id]['submitted'] = datetime.now()
         tracker = None if track is False else msg['tracker']
         ar = AsyncResult(self, [msg_id], fname=f.__name__, targets=targets, tracker=tracker)
         if block:
             try:
                 return ar.get()
             except KeyboardInterrupt:
                 return ar
         else:
             return ar
     
     def _apply_direct(self, f, args, kwargs, bound=None, block=None, targets=None,
                                         track=None):
         """Then underlying method for applying functions to specific engines
         via the MUX queue.
         
         This is a private method, see `apply` for details.
         Not to be called directly!
         """
         
         if not self._mux_ident:
             msg = "Multiplexing is disabled"
             raise RuntimeError(msg)
         
         loc = locals()
         for name in ('bound', 'block', 'targets', 'track'):
             assert loc[name] is not None, "kwarg %r must be specified!"%name
         
         idents,targets = self._build_targets(targets)
         
         subheader = {}
         content = dict(bound=bound)
         bufs = util.pack_apply_message(f,args,kwargs)
         
         msg_ids = []
         trackers = []
         for ident in idents:
             msg = self.session.send(self._apply_socket, "apply_request", 
                     content=content, buffers=bufs, ident=[self._mux_ident, ident], subheader=subheader,
                     track=track)
             if track:
                 trackers.append(msg['tracker'])
             msg_id = msg['msg_id']
             self.outstanding.add(msg_id)
             self._outstanding_dict[ident].add(msg_id)
             self.history.append(msg_id)
             msg_ids.append(msg_id)
         
         tracker = None if track is False else zmq.MessageTracker(*trackers)
         ar = AsyncResult(self, msg_ids, fname=f.__name__, targets=targets, tracker=tracker)
         
         if block:
             try:
                 return ar.get()
             except KeyboardInterrupt:
                 return ar
         else:
             return ar
     
     #--------------------------------------------------------------------------
     # construct a View object
     #--------------------------------------------------------------------------
     
     @defaultblock
     def remote(self, bound=False, block=None, targets=None, balanced=None):
         """Decorator for making a RemoteFunction"""
         return remote(self, bound=bound, targets=targets, block=block, balanced=balanced)
     
     @defaultblock
     def parallel(self, dist='b', bound=False, block=None, targets=None, balanced=None):
         """Decorator for making a ParallelFunction"""
         return parallel(self, bound=bound, targets=targets, block=block, balanced=balanced)
     
     def _cache_view(self, targets, balanced):
         """save views, so subsequent requests don't create new objects."""
         if balanced:
             view_class = LoadBalancedView
             view_cache = self._balanced_views
         else:
             view_class = DirectView
             view_cache = self._direct_views
         
         # use str, since often targets will be a list
         key = str(targets)
         if key not in view_cache:
             view_cache[key] = view_class(client=self, targets=targets)
         
         return view_cache[key]
     
     def view(self, targets=None, balanced=None):
         """Method for constructing View objects.
         
         If no arguments are specified, create a LoadBalancedView
         using all engines.  If only `targets` specified, it will
         be a DirectView.  This method is the underlying implementation
         of ``client.__getitem__``.
         
         Parameters
         ----------
         
         targets: list,slice,int,etc. [default: use all engines]
             The engines to use for the View
         balanced : bool [default: False if targets specified, True else]
             whether to build a LoadBalancedView or a DirectView
         
         """
         
         balanced = (targets is None) if balanced is None else balanced
         
         if targets is None:
             if balanced:
                 return self._cache_view(None,True)
             else:
                 targets = slice(None)
         
         if isinstance(targets, int):
             if targets < 0:
                 targets = self.ids[targets]
             if targets not in self.ids:
                 raise IndexError("No such engine: %i"%targets)
             return self._cache_view(targets, balanced)
         
         if isinstance(targets, slice):
             indices = range(len(self.ids))[targets]
             ids = sorted(self._ids)
             targets = [ ids[i] for i in indices ]
         
         if isinstance(targets, (tuple, list, xrange)):
             _,targets = self._build_targets(list(targets))
             return self._cache_view(targets, balanced)
         else:
             raise TypeError("targets by int/slice/collection of ints only, not %s"%(type(targets)))
     
     #--------------------------------------------------------------------------
     # Data movement
     #--------------------------------------------------------------------------
     
     @defaultblock
     def push(self, ns, targets='all', block=None, track=False):
         """Push the contents of `ns` into the namespace on `target`"""
         if not isinstance(ns, dict):
             raise TypeError("Must be a dict, not %s"%type(ns))
         result = self.apply(_push, kwargs=ns, targets=targets, block=block, bound=True, balanced=False, track=track)
         if not block:
             return result
     
     @defaultblock
     def pull(self, keys, targets='all', block=None):
         """Pull objects from `target`'s namespace by `keys`"""
         if isinstance(keys, basestring):
             pass
         elif isinstance(keys, (list,tuple,set)):
             for key in keys:
                 if not isinstance(key, basestring):
                     raise TypeError("keys must be str, not type %r"%type(key))
         else:
             raise TypeError("keys must be strs, not %r"%keys)
         result = self.apply(_pull, (keys,), targets=targets, block=block, bound=True, balanced=False)
         return result
     
     @defaultblock
     def scatter(self, key, seq, dist='b', flatten=False, targets='all', block=None, track=False):
         """
         Partition a Python sequence and send the partitions to a set of engines.
         """
         targets = self._build_targets(targets)[-1]
         mapObject = Map.dists[dist]()
         nparts = len(targets)
         msg_ids = []
         trackers = []
         for index, engineid in enumerate(targets):
             partition = mapObject.getPartition(seq, index, nparts)
             if flatten and len(partition) == 1:
                 r = self.push({key: partition[0]}, targets=engineid, block=False, track=track)
             else:
                 r = self.push({key: partition}, targets=engineid, block=False, track=track)
             msg_ids.extend(r.msg_ids)
             if track:
                 trackers.append(r._tracker)
         
         if track:
             tracker = zmq.MessageTracker(*trackers)
         else:
             tracker = None
         
         r = AsyncResult(self, msg_ids, fname='scatter', targets=targets, tracker=tracker)
         if block:
             r.wait()
         else:
             return r
     
     @defaultblock
     def gather(self, key, dist='b', targets='all', block=None):
         """
         Gather a partitioned sequence on a set of engines as a single local seq.
         """
         
         targets = self._build_targets(targets)[-1]
         mapObject = Map.dists[dist]()
         msg_ids = []
         for index, engineid in enumerate(targets):
             msg_ids.extend(self.pull(key, targets=engineid,block=False).msg_ids)
         
         r = AsyncMapResult(self, msg_ids, mapObject, fname='gather')
         if block:
             return r.get()
         else:
             return r
     
     #--------------------------------------------------------------------------
     # Query methods
     #--------------------------------------------------------------------------
     
     @spinfirst
     @defaultblock
     def get_result(self, indices_or_msg_ids=None, block=None):
         """Retrieve a result by msg_id or history index, wrapped in an AsyncResult object.
         
         If the client already has the results, no request to the Hub will be made.
         
         This is a convenient way to construct AsyncResult objects, which are wrappers
         that include metadata about execution, and allow for awaiting results that
         were not submitted by this Client.
         
         It can also be a convenient way to retrieve the metadata associated with
         blocking execution, since it always retrieves
         
         Examples
         --------
         ::
         
             In [10]: r = client.apply()
         
         Parameters
         ----------
         
         indices_or_msg_ids : integer history index, str msg_id, or list of either
             The indices or msg_ids of indices to be retrieved
         
         block : bool
             Whether to wait for the result to be done
         
         Returns
         -------
         
         AsyncResult
             A single AsyncResult object will always be returned.
         
         AsyncHubResult
             A subclass of AsyncResult that retrieves results from the Hub
         
         """
         if indices_or_msg_ids is None:
             indices_or_msg_ids = -1
         
         if not isinstance(indices_or_msg_ids, (list,tuple)):
             indices_or_msg_ids = [indices_or_msg_ids]
         
         theids = []
         for id in indices_or_msg_ids:
             if isinstance(id, int):
                 id = self.history[id]
             if not isinstance(id, str):
                 raise TypeError("indices must be str or int, not %r"%id)
             theids.append(id)
         
         local_ids = filter(lambda msg_id: msg_id in self.history or msg_id in self.results, theids)
         remote_ids = filter(lambda msg_id: msg_id not in local_ids, theids)
         
         if remote_ids:
             ar = AsyncHubResult(self, msg_ids=theids)
         else:
             ar = AsyncResult(self, msg_ids=theids)
         
         if block:
             ar.wait()
         
         return ar
     
     @spinfirst
     def result_status(self, msg_ids, status_only=True):
         """Check on the status of the result(s) of the apply request with `msg_ids`.
         
         If status_only is False, then the actual results will be retrieved, else
         only the status of the results will be checked.
         
         Parameters
         ----------
         
         msg_ids : list of msg_ids
             if int:
                 Passed as index to self.history for convenience.
         status_only : bool (default: True)
             if False:
                 Retrieve the actual results of completed tasks.
         
         Returns
         -------
         
         results : dict
             There will always be the keys 'pending' and 'completed', which will
             be lists of msg_ids that are incomplete or complete. If `status_only`
             is False, then completed results will be keyed by their `msg_id`.
         """
         if not isinstance(msg_ids, (list,tuple)):
             msg_ids = [msg_ids]
             
         theids = []
         for msg_id in msg_ids:
             if isinstance(msg_id, int):
                 msg_id = self.history[msg_id]
             if not isinstance(msg_id, basestring):
                 raise TypeError("msg_ids must be str, not %r"%msg_id)
             theids.append(msg_id)
         
         completed = []
         local_results = {}
         
         # comment this block out to temporarily disable local shortcut:
         for msg_id in theids:
             if msg_id in self.results:
                 completed.append(msg_id)
                 local_results[msg_id] = self.results[msg_id]
                 theids.remove(msg_id)
         
         if theids: # some not locally cached
             content = dict(msg_ids=theids, status_only=status_only)
             msg = self.session.send(self._query_socket, "result_request", content=content)
             zmq.select([self._query_socket], [], [])
             idents,msg = self.session.recv(self._query_socket, zmq.NOBLOCK)
             if self.debug:
                 pprint(msg)
             content = msg['content']
             if content['status'] != 'ok':
                 raise self._unwrap_exception(content)
             buffers = msg['buffers']
         else:
             content = dict(completed=[],pending=[])
         
         content['completed'].extend(completed)
         
         if status_only:
             return content
         
         failures = []
         # load cached results into result:
         content.update(local_results)
         # update cache with results:
         for msg_id in sorted(theids):
             if msg_id in content['completed']:
                 rec = content[msg_id]
                 parent = rec['header']
                 header = rec['result_header']
                 rcontent = rec['result_content']
                 iodict = rec['io']
                 if isinstance(rcontent, str):
                     rcontent = self.session.unpack(rcontent)
                 
                 md = self.metadata[msg_id]
                 md.update(self._extract_metadata(header, parent, rcontent))
                 md.update(iodict)
                 
                 if rcontent['status'] == 'ok':
                     res,buffers = util.unserialize_object(buffers)
                 else:
                     print rcontent
                     res = self._unwrap_exception(rcontent)
                     failures.append(res)
                 
                 self.results[msg_id] = res
                 content[msg_id] = res
         
         if len(theids) == 1 and failures:
                 raise failures[0]
         
         error.collect_exceptions(failures, "result_status")
         return content
 
     @spinfirst
     def queue_status(self, targets='all', verbose=False):
         """Fetch the status of engine queues.
         
         Parameters
         ----------
         
         targets : int/str/list of ints/strs
                 the engines whose states are to be queried.
                 default : all
         verbose : bool
                 Whether to return lengths only, or lists of ids for each element
         """
         targets = self._build_targets(targets)[1]
         content = dict(targets=targets, verbose=verbose)
         self.session.send(self._query_socket, "queue_request", content=content)
         idents,msg = self.session.recv(self._query_socket, 0)
         if self.debug:
             pprint(msg)
         content = msg['content']
         status = content.pop('status')
         if status != 'ok':
             raise self._unwrap_exception(content)
         return util.rekey(content)
         
     @spinfirst
     def purge_results(self, jobs=[], targets=[]):
         """Tell the controller to forget results.
         
         Individual results can be purged by msg_id, or the entire
         history of specific targets can be purged.
         
         Parameters
         ----------
         
         jobs : str or list of strs or AsyncResult objects
                 the msg_ids whose results should be forgotten.
         targets : int/str/list of ints/strs
                 The targets, by uuid or int_id, whose entire history is to be purged.
                 Use `targets='all'` to scrub everything from the controller's memory.
                 
                 default : None
         """
         if not targets and not jobs:
             raise ValueError("Must specify at least one of `targets` and `jobs`")
         if targets:
             targets = self._build_targets(targets)[1]
         
         # construct msg_ids from jobs
         msg_ids = []
         if isinstance(jobs, (basestring,AsyncResult)):
             jobs = [jobs]
         bad_ids = filter(lambda obj: not isinstance(obj, (basestring, AsyncResult)), jobs)
         if bad_ids:
             raise TypeError("Invalid msg_id type %r, expected str or AsyncResult"%bad_ids[0])
         for j in jobs:
             if isinstance(j, AsyncResult):
                 msg_ids.extend(j.msg_ids)
             else:
                 msg_ids.append(j)
         
         content = dict(targets=targets, msg_ids=msg_ids)
         self.session.send(self._query_socket, "purge_request", content=content)
         idents, msg = self.session.recv(self._query_socket, 0)
         if self.debug:
             pprint(msg)
         content = msg['content']
         if content['status'] != 'ok':
             raise self._unwrap_exception(content)
 
 
 __all__ = [ 'Client', 
             'depend', 
             'require', 
             'remote',
             'parallel',
             'RemoteFunction',
             'ParallelFunction',
             'DirectView',
             'LoadBalancedView',
             'AsyncResult',
             'AsyncMapResult',
             'Reference'
             ]

IPython/zmq/parallel/tests/clienttest.py

@@ -1,105 +1,106 b''
 import sys
 import tempfile
 import time
 from signal import SIGINT
 from multiprocessing import Process
 
 from nose import SkipTest
 
 from zmq.tests import BaseZMQTestCase
 
 from IPython.external.decorator import decorator
 
 from IPython.zmq.parallel import error
 from IPython.zmq.parallel.client import Client
 from IPython.zmq.parallel.ipcluster import launch_process
 from IPython.zmq.parallel.entry_point import select_random_ports
 from IPython.zmq.parallel.tests import processes,add_engine
 
 # simple tasks for use in apply tests
 
 def segfault():
     """this will segfault"""
     import ctypes
     ctypes.memset(-1,0,1)
 
 def wait(n):
     """sleep for a time"""
     import time
     time.sleep(n)
     return n
 
 def raiser(eclass):
     """raise an exception"""
     raise eclass()
 
 # test decorator for skipping tests when libraries are unavailable
 def skip_without(*names):
     """skip a test if some names are not importable"""
     @decorator
     def skip_without_names(f, *args, **kwargs):
         """decorator to skip tests in the absence of numpy."""
         for name in names:
             try:
                 __import__(name)
             except ImportError:
                 raise SkipTest
         return f(*args, **kwargs)
     return skip_without_names
 
 
 class ClusterTestCase(BaseZMQTestCase):
     
     def add_engines(self, n=1, block=True):
         """add multiple engines to our cluster"""
         for i in range(n):
             self.engines.append(add_engine())
         if block:
             self.wait_on_engines()
     
     def wait_on_engines(self, timeout=5):
         """wait for our engines to connect."""
         n = len(self.engines)+self.base_engine_count
         tic = time.time()
         while time.time()-tic < timeout and len(self.client.ids) < n:
             time.sleep(0.1)
         
         assert not len(self.client.ids) < n, "waiting for engines timed out"
     
     def connect_client(self):
         """connect a client with my Context, and track its sockets for cleanup"""
         c = Client(profile='iptest',context=self.context)
-        for name in filter(lambda n:n.endswith('socket'), dir(c)):
-            self.sockets.append(getattr(c, name))
+        
+        # for name in filter(lambda n:n.endswith('socket'), dir(c)):
+        #     self.sockets.append(getattr(c, name))
         return c
     
     def assertRaisesRemote(self, etype, f, *args, **kwargs):
         try:
             try:
                 f(*args, **kwargs)
             except error.CompositeError as e:
                 e.raise_exception()
         except error.RemoteError as e:
             self.assertEquals(etype.__name__, e.ename, "Should have raised %r, but raised %r"%(e.ename, etype.__name__))
         else:
             self.fail("should have raised a RemoteError")
             
     def setUp(self):
         BaseZMQTestCase.setUp(self)
         self.client = self.connect_client()
         self.base_engine_count=len(self.client.ids)
         self.engines=[]
     
     def tearDown(self):
         
         # close fds:
         for e in filter(lambda e: e.poll() is not None, processes):
             processes.remove(e)
         
         self.client.close()
         BaseZMQTestCase.tearDown(self)
         # this will be superfluous when pyzmq merges PR #88
         self.context.term()
-        print tempfile.TemporaryFile().fileno(),
-        sys.stdout.flush()
+        # print tempfile.TemporaryFile().fileno(),
+        # sys.stdout.flush()
         
  No newline at end of file

IPython/zmq/parallel/tests/test_client.py

@@ -1,262 +1,262 b''
 import time
 from tempfile import mktemp
 
-import nose.tools as nt
 import zmq
 
 from IPython.zmq.parallel import client as clientmod
 from IPython.zmq.parallel import error
 from IPython.zmq.parallel.asyncresult import AsyncResult, AsyncHubResult
 from IPython.zmq.parallel.view import LoadBalancedView, DirectView
 
 from clienttest import ClusterTestCase, segfault, wait
 
 class TestClient(ClusterTestCase):
     
     def test_ids(self):
         n = len(self.client.ids)
         self.add_engines(3)
         self.assertEquals(len(self.client.ids), n+3)
     
     def test_segfault_task(self):
         """test graceful handling of engine death (balanced)"""
         self.add_engines(1)
         ar = self.client.apply(segfault, block=False)
         self.assertRaisesRemote(error.EngineError, ar.get)
         eid = ar.engine_id
         while eid in self.client.ids:
             time.sleep(.01)
             self.client.spin()
     
     def test_segfault_mux(self):
         """test graceful handling of engine death (direct)"""
         self.add_engines(1)
         eid = self.client.ids[-1]
         ar = self.client[eid].apply_async(segfault)
         self.assertRaisesRemote(error.EngineError, ar.get)
         eid = ar.engine_id
         while eid in self.client.ids:
             time.sleep(.01)
             self.client.spin()
     
     def test_view_indexing(self):
         """test index access for views"""
         self.add_engines(2)
         targets = self.client._build_targets('all')[-1]
         v = self.client[:]
         self.assertEquals(v.targets, targets)
         t = self.client.ids[2]
         v = self.client[t]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, t)
         t = self.client.ids[2:4]
         v = self.client[t]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, t)
         v = self.client[::2]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, targets[::2])
         v = self.client[1::3]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, targets[1::3])
         v = self.client[:-3]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, targets[:-3])
         v = self.client[-1]
         self.assert_(isinstance(v, DirectView))
         self.assertEquals(v.targets, targets[-1])
-        nt.assert_raises(TypeError, lambda : self.client[None])
+        self.assertRaises(TypeError, lambda : self.client[None])
     
     def test_view_cache(self):
         """test that multiple view requests return the same object"""
         v = self.client[:2]
         v2 =self.client[:2]
         self.assertTrue(v is v2)
         v = self.client.view()
         v2 = self.client.view(balanced=True)
         self.assertTrue(v is v2)
     
     def test_targets(self):
         """test various valid targets arguments"""
         build = self.client._build_targets
         ids = self.client.ids
         idents,targets = build(None)
         self.assertEquals(ids, targets)
     
     def test_clear(self):
         """test clear behavior"""
         self.add_engines(2)
         self.client.block=True
         self.client.push(dict(a=5))
         self.client.pull('a')
         id0 = self.client.ids[-1]
         self.client.clear(targets=id0)
         self.client.pull('a', targets=self.client.ids[:-1])
         self.assertRaisesRemote(NameError, self.client.pull, 'a')
         self.client.clear()
         for i in self.client.ids:
             self.assertRaisesRemote(NameError, self.client.pull, 'a', targets=i)
             
     
     def test_push_pull(self):
         """test pushing and pulling"""
         data = dict(a=10, b=1.05, c=range(10), d={'e':(1,2),'f':'hi'})
         t = self.client.ids[-1]
         self.add_engines(2)
         push = self.client.push
         pull = self.client.pull
         self.client.block=True
         nengines = len(self.client)
         push({'data':data}, targets=t)
         d = pull('data', targets=t)
         self.assertEquals(d, data)
         push({'data':data})
         d = pull('data')
         self.assertEquals(d, nengines*[data])
         ar = push({'data':data}, block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         r = ar.get()
         ar = pull('data', block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         r = ar.get()
         self.assertEquals(r, nengines*[data])
         push(dict(a=10,b=20))
         r = pull(('a','b'))
         self.assertEquals(r, nengines*[[10,20]])
     
     def test_push_pull_function(self):
         "test pushing and pulling functions"
         def testf(x):
             return 2.0*x
         
         self.add_engines(4)
         t = self.client.ids[-1]
         self.client.block=True
         push = self.client.push
         pull = self.client.pull
         execute = self.client.execute
         push({'testf':testf}, targets=t)
         r = pull('testf', targets=t)
         self.assertEqual(r(1.0), testf(1.0))
         execute('r = testf(10)', targets=t)
         r = pull('r', targets=t)
         self.assertEquals(r, testf(10))
         ar = push({'testf':testf}, block=False)
         ar.get()
         ar = pull('testf', block=False)
         rlist = ar.get()
         for r in rlist:
             self.assertEqual(r(1.0), testf(1.0))
         execute("def g(x): return x*x", targets=t)
         r = pull(('testf','g'),targets=t)
         self.assertEquals((r[0](10),r[1](10)), (testf(10), 100))
     
     def test_push_function_globals(self):
         """test that pushed functions have access to globals"""
         def geta():
             return a
         self.add_engines(1)
         v = self.client[-1]
         v.block=True
         v['f'] = geta
         self.assertRaisesRemote(NameError, v.execute, 'b=f()')
         v.execute('a=5')
         v.execute('b=f()')
         self.assertEquals(v['b'], 5)
     
     def test_push_function_defaults(self):
         """test that pushed functions preserve default args"""
         def echo(a=10):
             return a
         self.add_engines(1)
         v = self.client[-1]
         v.block=True
         v['f'] = echo
         v.execute('b=f()')
         self.assertEquals(v['b'], 10)
 
     def test_get_result(self):
         """test getting results from the Hub."""
         c = clientmod.Client(profile='iptest')
         self.add_engines(1)
+        t = c.ids[-1]
         ar = c.apply(wait, (1,), block=False, targets=t)
         # give the monitor time to notice the message
         time.sleep(.25)
         ahr = self.client.get_result(ar.msg_ids)
         self.assertTrue(isinstance(ahr, AsyncHubResult))
         self.assertEquals(ahr.get(), ar.get())
         ar2 = self.client.get_result(ar.msg_ids)
         self.assertFalse(isinstance(ar2, AsyncHubResult))
     
     def test_ids_list(self):
         """test client.ids"""
         self.add_engines(2)
         ids = self.client.ids
         self.assertEquals(ids, self.client._ids)
         self.assertFalse(ids is self.client._ids)
         ids.remove(ids[-1])
         self.assertNotEquals(ids, self.client._ids)
     
     def test_run_newline(self):
         """test that run appends newline to files"""
         tmpfile = mktemp()
         with open(tmpfile, 'w') as f:
             f.write("""def g():
                 return 5
                 """)
         v = self.client[-1]
         v.run(tmpfile, block=True)
         self.assertEquals(v.apply_sync(lambda : g()), 5)
 
     def test_apply_tracked(self):
         """test tracking for apply"""
         # self.add_engines(1)
         t = self.client.ids[-1]
         self.client.block=False
         def echo(n=1024*1024, **kwargs):
             return self.client.apply(lambda x: x, args=('x'*n,), targets=t, **kwargs)
         ar = echo(1)
         self.assertTrue(ar._tracker is None)
         self.assertTrue(ar.sent)
         ar = echo(track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertEquals(ar.sent, ar._tracker.done)
         ar._tracker.wait()
         self.assertTrue(ar.sent)
         
     def test_push_tracked(self):
         t = self.client.ids[-1]
         ns = dict(x='x'*1024*1024)
         ar = self.client.push(ns, targets=t, block=False)
         self.assertTrue(ar._tracker is None)
         self.assertTrue(ar.sent)
         
         ar = self.client.push(ns, targets=t, block=False, track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertEquals(ar.sent, ar._tracker.done)
         ar._tracker.wait()
         self.assertTrue(ar.sent)
         ar.get()
         
     def test_scatter_tracked(self):
         t = self.client.ids
         x='x'*1024*1024
         ar = self.client.scatter('x', x, targets=t, block=False)
         self.assertTrue(ar._tracker is None)
         self.assertTrue(ar.sent)
         
         ar = self.client.scatter('x', x, targets=t, block=False, track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertEquals(ar.sent, ar._tracker.done)
         ar._tracker.wait()
         self.assertTrue(ar.sent)
         ar.get()
     
     def test_remote_reference(self):
         v = self.client[-1]
         v['a'] = 123
         ra = clientmod.Reference('a')
         b = v.apply_sync(lambda x: x, ra)
         self.assertEquals(b, 123)
 
 

IPython/zmq/parallel/tests/test_newserialized.py

@@ -1,89 +1,87 b''
 """test serialization with newserialized"""
 
 from unittest import TestCase
 
-import nose.tools as nt
-
 from IPython.testing.parametric import parametric
 from IPython.utils import newserialized as ns
 from IPython.utils.pickleutil import can, uncan, CannedObject, CannedFunction
 from IPython.zmq.parallel.tests.clienttest import skip_without
 
 
 class CanningTestCase(TestCase):
     def test_canning(self):
         d = dict(a=5,b=6)
         cd = can(d)
-        nt.assert_true(isinstance(cd, dict))
+        self.assertTrue(isinstance(cd, dict))
 
     def test_canned_function(self):
         f = lambda : 7
         cf = can(f)
-        nt.assert_true(isinstance(cf, CannedFunction))
+        self.assertTrue(isinstance(cf, CannedFunction))
     
     @parametric
     def test_can_roundtrip(cls):
         objs = [
             dict(),
             set(),
             list(),
             ['a',1,['a',1],u'e'],
         ]
         return map(cls.run_roundtrip, objs)
     
     @classmethod
-    def run_roundtrip(cls, obj):
+    def run_roundtrip(self, obj):
         o = uncan(can(obj))
-        nt.assert_equals(obj, o)
+        assert o == obj, "failed assertion: %r == %r"%(o,obj)
     
     def test_serialized_interfaces(self):
 
         us = {'a':10, 'b':range(10)}
         s = ns.serialize(us)
         uus = ns.unserialize(s)
-        nt.assert_true(isinstance(s, ns.SerializeIt))
-        nt.assert_equals(uus, us)
+        self.assertTrue(isinstance(s, ns.SerializeIt))
+        self.assertEquals(uus, us)
 
     def test_pickle_serialized(self):
         obj = {'a':1.45345, 'b':'asdfsdf', 'c':10000L}
         original = ns.UnSerialized(obj)
         originalSer = ns.SerializeIt(original)
         firstData = originalSer.getData()
         firstTD = originalSer.getTypeDescriptor()
         firstMD = originalSer.getMetadata()
-        nt.assert_equals(firstTD, 'pickle')
-        nt.assert_equals(firstMD, {})
+        self.assertEquals(firstTD, 'pickle')
+        self.assertEquals(firstMD, {})
         unSerialized = ns.UnSerializeIt(originalSer)
         secondObj = unSerialized.getObject()
         for k, v in secondObj.iteritems():
-            nt.assert_equals(obj[k], v)
+            self.assertEquals(obj[k], v)
         secondSer = ns.SerializeIt(ns.UnSerialized(secondObj))
-        nt.assert_equals(firstData, secondSer.getData())
-        nt.assert_equals(firstTD, secondSer.getTypeDescriptor() )
-        nt.assert_equals(firstMD, secondSer.getMetadata())
+        self.assertEquals(firstData, secondSer.getData())
+        self.assertEquals(firstTD, secondSer.getTypeDescriptor() )
+        self.assertEquals(firstMD, secondSer.getMetadata())
     
     @skip_without('numpy')
     def test_ndarray_serialized(self):
         import numpy
         a = numpy.linspace(0.0, 1.0, 1000)
         unSer1 = ns.UnSerialized(a)
         ser1 = ns.SerializeIt(unSer1)
         td = ser1.getTypeDescriptor()
-        nt.assert_equals(td, 'ndarray')
+        self.assertEquals(td, 'ndarray')
         md = ser1.getMetadata()
-        nt.assert_equals(md['shape'], a.shape)
-        nt.assert_equals(md['dtype'], a.dtype.str)
+        self.assertEquals(md['shape'], a.shape)
+        self.assertEquals(md['dtype'], a.dtype.str)
         buff = ser1.getData()
-        nt.assert_equals(buff, numpy.getbuffer(a))
+        self.assertEquals(buff, numpy.getbuffer(a))
         s = ns.Serialized(buff, td, md)
         final = ns.unserialize(s)
-        nt.assert_equals(numpy.getbuffer(a), numpy.getbuffer(final))
-        nt.assert_true((a==final).all())
-        nt.assert_equals(a.dtype.str, final.dtype.str)
-        nt.assert_equals(a.shape, final.shape)
+        self.assertEquals(numpy.getbuffer(a), numpy.getbuffer(final))
+        self.assertTrue((a==final).all())
+        self.assertEquals(a.dtype.str, final.dtype.str)
+        self.assertEquals(a.shape, final.shape)
         # test non-copying:
         a[2] = 1e9
-        nt.assert_true((a==final).all())
+        self.assertTrue((a==final).all())
         
         
         
  No newline at end of file