Parallel: Support get/set of nested objects in view (e.g. dv['a.b'])

IPython/parallel/tests/test_view.py

@@ -1,678 +1,696 b''
 # -*- coding: utf-8 -*-
 """test View objects
 
 Authors:
 
 * Min RK
 """
 #-------------------------------------------------------------------------------
 #  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
 #-------------------------------------------------------------------------------
 
 import sys
 import platform
 import time
 from tempfile import mktemp
 from StringIO import StringIO
 
 import zmq
 from nose import SkipTest
 
 from IPython.testing import decorators as dec
 from IPython.testing.ipunittest import ParametricTestCase
 
 from IPython import parallel  as pmod
 from IPython.parallel import error
 from IPython.parallel import AsyncResult, AsyncHubResult, AsyncMapResult
 from IPython.parallel import DirectView
 from IPython.parallel.util import interactive
 
 from IPython.parallel.tests import add_engines
 
 from .clienttest import ClusterTestCase, crash, wait, skip_without
 
 def setup():
     add_engines(3, total=True)
 
 class TestView(ClusterTestCase, ParametricTestCase):
     
     def setUp(self):
         # On Win XP, wait for resource cleanup, else parallel test group fails
         if platform.system() == "Windows" and platform.win32_ver()[0] == "XP":
             # 1 sec fails. 1.5 sec seems ok. Using 2 sec for margin of safety
             time.sleep(2)
         super(TestView, self).setUp()
 
     def test_z_crash_mux(self):
         """test graceful handling of engine death (direct)"""
         raise SkipTest("crash tests disabled, due to undesirable crash reports")
         # self.add_engines(1)
         eid = self.client.ids[-1]
         ar = self.client[eid].apply_async(crash)
         self.assertRaisesRemote(error.EngineError, ar.get, 10)
         eid = ar.engine_id
         tic = time.time()
         while eid in self.client.ids and time.time()-tic < 5:
             time.sleep(.01)
             self.client.spin()
         self.assertFalse(eid in self.client.ids, "Engine should have died")
     
     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]
         v = self.client[t]
         push = v.push
         pull = v.pull
         v.block=True
         nengines = len(self.client)
         push({'data':data})
         d = pull('data')
         self.assertEqual(d, data)
         self.client[:].push({'data':data})
         d = self.client[:].pull('data', block=True)
         self.assertEqual(d, nengines*[data])
         ar = push({'data':data}, block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         r = ar.get()
         ar = self.client[:].pull('data', block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         r = ar.get()
         self.assertEqual(r, nengines*[data])
         self.client[:].push(dict(a=10,b=20))
         r = self.client[:].pull(('a','b'), block=True)
         self.assertEqual(r, nengines*[[10,20]])
     
     def test_push_pull_function(self):
         "test pushing and pulling functions"
         def testf(x):
             return 2.0*x
         
         t = self.client.ids[-1]
         v = self.client[t]
         v.block=True
         push = v.push
         pull = v.pull
         execute = v.execute
         push({'testf':testf})
         r = pull('testf')
         self.assertEqual(r(1.0), testf(1.0))
         execute('r = testf(10)')
         r = pull('r')
         self.assertEqual(r, testf(10))
         ar = self.client[:].push({'testf':testf}, block=False)
         ar.get()
         ar = self.client[:].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")
         r = pull(('testf','g'))
         self.assertEqual((r[0](10),r[1](10)), (testf(10), 100))
     
     def test_push_function_globals(self):
         """test that pushed functions have access to globals"""
         @interactive
         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.assertEqual(v['b'], 5)
     
     def test_push_function_defaults(self):
         """test that pushed functions preserve default args"""
         def echo(a=10):
             return a
         v = self.client[-1]
         v.block=True
         v['f'] = echo
         v.execute('b=f()')
         self.assertEqual(v['b'], 10)
 
     def test_get_result(self):
         """test getting results from the Hub."""
         c = pmod.Client(profile='iptest')
         # self.add_engines(1)
         t = c.ids[-1]
         v = c[t]
         v2 = self.client[t]
         ar = v.apply_async(wait, 1)
         # give the monitor time to notice the message
         time.sleep(.25)
         ahr = v2.get_result(ar.msg_ids)
         self.assertTrue(isinstance(ahr, AsyncHubResult))
         self.assertEqual(ahr.get(), ar.get())
         ar2 = v2.get_result(ar.msg_ids)
         self.assertFalse(isinstance(ar2, AsyncHubResult))
         c.spin()
         c.close()
     
     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.assertEqual(v.apply_sync(lambda f: f(), pmod.Reference('g')), 5)
 
     def test_apply_tracked(self):
         """test tracking for apply"""
         # self.add_engines(1)
         t = self.client.ids[-1]
         v = self.client[t]
         v.block=False
         def echo(n=1024*1024, **kwargs):
             with v.temp_flags(**kwargs):
                 return v.apply(lambda x: x, 'x'*n)
         ar = echo(1, track=False)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertTrue(ar.sent)
         ar = echo(track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertEqual(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)
         v = self.client[t]
         ar = v.push(ns, block=False, track=False)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertTrue(ar.sent)
         
         ar = v.push(ns, block=False, track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         ar._tracker.wait()
         self.assertEqual(ar.sent, ar._tracker.done)
         self.assertTrue(ar.sent)
         ar.get()
         
     def test_scatter_tracked(self):
         t = self.client.ids
         x='x'*1024*1024
         ar = self.client[t].scatter('x', x, block=False, track=False)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertTrue(ar.sent)
         
         ar = self.client[t].scatter('x', x, block=False, track=True)
         self.assertTrue(isinstance(ar._tracker, zmq.MessageTracker))
         self.assertEqual(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 = pmod.Reference('a')
         b = v.apply_sync(lambda x: x, ra)
         self.assertEqual(b, 123)
 
 
     def test_scatter_gather(self):
         view = self.client[:]
         seq1 = range(16)
         view.scatter('a', seq1)
         seq2 = view.gather('a', block=True)
         self.assertEqual(seq2, seq1)
         self.assertRaisesRemote(NameError, view.gather, 'asdf', block=True)
     
     @skip_without('numpy')
     def test_scatter_gather_numpy(self):
         import numpy
         from numpy.testing.utils import assert_array_equal, assert_array_almost_equal
         view = self.client[:]
         a = numpy.arange(64)
         view.scatter('a', a, block=True)
         b = view.gather('a', block=True)
         assert_array_equal(b, a)
     
     def test_scatter_gather_lazy(self):
         """scatter/gather with targets='all'"""
         view = self.client.direct_view(targets='all')
         x = range(64)
         view.scatter('x', x)
         gathered = view.gather('x', block=True)
         self.assertEqual(gathered, x)
         
 
     @dec.known_failure_py3
     @skip_without('numpy')
     def test_push_numpy_nocopy(self):
         import numpy
         view = self.client[:]
         a = numpy.arange(64)
         view['A'] = a
         @interactive
         def check_writeable(x):
             return x.flags.writeable
         
         for flag in view.apply_sync(check_writeable, pmod.Reference('A')):
             self.assertFalse(flag, "array is writeable, push shouldn't have pickled it")
         
         view.push(dict(B=a))
         for flag in view.apply_sync(check_writeable, pmod.Reference('B')):
             self.assertFalse(flag, "array is writeable, push shouldn't have pickled it")
     
     @skip_without('numpy')
     def test_apply_numpy(self):
         """view.apply(f, ndarray)"""
         import numpy
         from numpy.testing.utils import assert_array_equal, assert_array_almost_equal
         
         A = numpy.random.random((100,100))
         view = self.client[-1]
         for dt in [ 'int32', 'uint8', 'float32', 'float64' ]:
             B = A.astype(dt)
             C = view.apply_sync(lambda x:x, B)
             assert_array_equal(B,C)
     
     @skip_without('numpy')
     def test_push_pull_recarray(self):
         """push/pull recarrays"""
         import numpy
         from numpy.testing.utils import assert_array_equal
         
         view = self.client[-1]
         
         R = numpy.array([
             (1, 'hi', 0.),
             (2**30, 'there', 2.5),
             (-99999, 'world', -12345.6789),
         ], [('n', int), ('s', '|S10'), ('f', float)])
         
         view['RR'] = R
         R2 = view['RR']
         
         r_dtype, r_shape = view.apply_sync(interactive(lambda : (RR.dtype, RR.shape)))
         self.assertEqual(r_dtype, R.dtype)
         self.assertEqual(r_shape, R.shape)
         self.assertEqual(R2.dtype, R.dtype)
         self.assertEqual(R2.shape, R.shape)
         assert_array_equal(R2, R)
     
     def test_map(self):
         view = self.client[:]
         def f(x):
             return x**2
         data = range(16)
         r = view.map_sync(f, data)
         self.assertEqual(r, map(f, data))
     
     def test_map_iterable(self):
         """test map on iterables (direct)"""
         view = self.client[:]
         # 101 is prime, so it won't be evenly distributed
         arr = range(101)
         # ensure it will be an iterator, even in Python 3
         it = iter(arr)
         r = view.map_sync(lambda x:x, arr)
         self.assertEqual(r, list(arr))
     
     def test_scatter_gather_nonblocking(self):
         data = range(16)
         view = self.client[:]
         view.scatter('a', data, block=False)
         ar = view.gather('a', block=False)
         self.assertEqual(ar.get(), data)
     
     @skip_without('numpy')
     def test_scatter_gather_numpy_nonblocking(self):
         import numpy
         from numpy.testing.utils import assert_array_equal, assert_array_almost_equal
         a = numpy.arange(64)
         view = self.client[:]
         ar = view.scatter('a', a, block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         amr = view.gather('a', block=False)
         self.assertTrue(isinstance(amr, AsyncMapResult))
         assert_array_equal(amr.get(), a)
 
     def test_execute(self):
         view = self.client[:]
         # self.client.debug=True
         execute = view.execute
         ar = execute('c=30', block=False)
         self.assertTrue(isinstance(ar, AsyncResult))
         ar = execute('d=[0,1,2]', block=False)
         self.client.wait(ar, 1)
         self.assertEqual(len(ar.get()), len(self.client))
         for c in view['c']:
             self.assertEqual(c, 30)
     
     def test_abort(self):
         view = self.client[-1]
         ar = view.execute('import time; time.sleep(1)', block=False)
         ar2 = view.apply_async(lambda : 2)
         ar3 = view.apply_async(lambda : 3)
         view.abort(ar2)
         view.abort(ar3.msg_ids)
         self.assertRaises(error.TaskAborted, ar2.get)
         self.assertRaises(error.TaskAborted, ar3.get)
     
     def test_abort_all(self):
         """view.abort() aborts all outstanding tasks"""
         view = self.client[-1]
         ars = [ view.apply_async(time.sleep, 0.25) for i in range(10) ]
         view.abort()
         view.wait(timeout=5)
         for ar in ars[5:]:
             self.assertRaises(error.TaskAborted, ar.get)
     
     def test_temp_flags(self):
         view = self.client[-1]
         view.block=True
         with view.temp_flags(block=False):
             self.assertFalse(view.block)
         self.assertTrue(view.block)
     
     @dec.known_failure_py3
     def test_importer(self):
         view = self.client[-1]
         view.clear(block=True)
         with view.importer:
             import re
         
         @interactive
         def findall(pat, s):
             # this globals() step isn't necessary in real code
             # only to prevent a closure in the test
             re = globals()['re']
             return re.findall(pat, s)
         
         self.assertEqual(view.apply_sync(findall, '\w+', 'hello world'), 'hello world'.split())
     
     def test_unicode_execute(self):
         """test executing unicode strings"""
         v = self.client[-1]
         v.block=True
         if sys.version_info[0] >= 3:
             code="a='é'"
         else:
             code=u"a=u'é'"
         v.execute(code)
         self.assertEqual(v['a'], u'é')
         
     def test_unicode_apply_result(self):
         """test unicode apply results"""
         v = self.client[-1]
         r = v.apply_sync(lambda : u'é')
         self.assertEqual(r, u'é')
     
     def test_unicode_apply_arg(self):
         """test passing unicode arguments to apply"""
         v = self.client[-1]
         
         @interactive
         def check_unicode(a, check):
             assert isinstance(a, unicode), "%r is not unicode"%a
             assert isinstance(check, bytes), "%r is not bytes"%check
             assert a.encode('utf8') == check, "%s != %s"%(a,check)
         
         for s in [ u'é', u'ßø®∫',u'asdf' ]:
             try:
                 v.apply_sync(check_unicode, s, s.encode('utf8'))
             except error.RemoteError as e:
                 if e.ename == 'AssertionError':
                     self.fail(e.evalue)
                 else:
                     raise e
     
     def test_map_reference(self):
         """view.map(<Reference>, *seqs) should work"""
         v = self.client[:]
         v.scatter('n', self.client.ids, flatten=True)
         v.execute("f = lambda x,y: x*y")
         rf = pmod.Reference('f')
         nlist = list(range(10))
         mlist = nlist[::-1]
         expected = [ m*n for m,n in zip(mlist, nlist) ]
         result = v.map_sync(rf, mlist, nlist)
         self.assertEqual(result, expected)
 
     def test_apply_reference(self):
         """view.apply(<Reference>, *args) should work"""
         v = self.client[:]
         v.scatter('n', self.client.ids, flatten=True)
         v.execute("f = lambda x: n*x")
         rf = pmod.Reference('f')
         result = v.apply_sync(rf, 5)
         expected = [ 5*id for id in self.client.ids ]
         self.assertEqual(result, expected)
     
     def test_eval_reference(self):
         v = self.client[self.client.ids[0]]
         v['g'] = range(5)
         rg = pmod.Reference('g[0]')
         echo = lambda x:x
         self.assertEqual(v.apply_sync(echo, rg), 0)
     
     def test_reference_nameerror(self):
         v = self.client[self.client.ids[0]]
         r = pmod.Reference('elvis_has_left')
         echo = lambda x:x
         self.assertRaisesRemote(NameError, v.apply_sync, echo, r)
 
     def test_single_engine_map(self):
         e0 = self.client[self.client.ids[0]]
         r = range(5)
         check = [ -1*i for i in r ]
         result = e0.map_sync(lambda x: -1*x, r)
         self.assertEqual(result, check)
     
     def test_len(self):
         """len(view) makes sense"""
         e0 = self.client[self.client.ids[0]]
         yield self.assertEqual(len(e0), 1)
         v = self.client[:]
         yield self.assertEqual(len(v), len(self.client.ids))
         v = self.client.direct_view('all')
         yield self.assertEqual(len(v), len(self.client.ids))
         v = self.client[:2]
         yield self.assertEqual(len(v), 2)
         v = self.client[:1]
         yield self.assertEqual(len(v), 1)
         v = self.client.load_balanced_view()
         yield self.assertEqual(len(v), len(self.client.ids))
         # parametric tests seem to require manual closing?
         self.client.close()
 
     
     # begin execute tests
     
     def test_execute_reply(self):
         e0 = self.client[self.client.ids[0]]
         e0.block = True
         ar = e0.execute("5", silent=False)
         er = ar.get()
         self.assertEqual(str(er), "<ExecuteReply[%i]: 5>" % er.execution_count)
         self.assertEqual(er.pyout['data']['text/plain'], '5')
 
     def test_execute_reply_stdout(self):
         e0 = self.client[self.client.ids[0]]
         e0.block = True
         ar = e0.execute("print (5)", silent=False)
         er = ar.get()
         self.assertEqual(er.stdout.strip(), '5')
         
     def test_execute_pyout(self):
         """execute triggers pyout with silent=False"""
         view = self.client[:]
         ar = view.execute("5", silent=False, block=True)
         
         expected = [{'text/plain' : '5'}] * len(view)
         mimes = [ out['data'] for out in ar.pyout ]
         self.assertEqual(mimes, expected)
     
     def test_execute_silent(self):
         """execute does not trigger pyout with silent=True"""
         view = self.client[:]
         ar = view.execute("5", block=True)
         expected = [None] * len(view)
         self.assertEqual(ar.pyout, expected)
     
     def test_execute_magic(self):
         """execute accepts IPython commands"""
         view = self.client[:]
         view.execute("a = 5")
         ar = view.execute("%whos", block=True)
         # this will raise, if that failed
         ar.get(5)
         for stdout in ar.stdout:
             lines = stdout.splitlines()
             self.assertEqual(lines[0].split(), ['Variable', 'Type', 'Data/Info'])
             found = False
             for line in lines[2:]:
                 split = line.split()
                 if split == ['a', 'int', '5']:
                     found = True
                     break
             self.assertTrue(found, "whos output wrong: %s" % stdout)
     
     def test_execute_displaypub(self):
         """execute tracks display_pub output"""
         view = self.client[:]
         view.execute("from IPython.core.display import *")
         ar = view.execute("[ display(i) for i in range(5) ]", block=True)
         
         expected = [ {u'text/plain' : unicode(j)} for j in range(5) ]
         for outputs in ar.outputs:
             mimes = [ out['data'] for out in outputs ]
             self.assertEqual(mimes, expected)
     
     def test_apply_displaypub(self):
         """apply tracks display_pub output"""
         view = self.client[:]
         view.execute("from IPython.core.display import *")
         
         @interactive
         def publish():
             [ display(i) for i in range(5) ]
         
         ar = view.apply_async(publish)
         ar.get(5)
         expected = [ {u'text/plain' : unicode(j)} for j in range(5) ]
         for outputs in ar.outputs:
             mimes = [ out['data'] for out in outputs ]
             self.assertEqual(mimes, expected)
     
     def test_execute_raises(self):
         """exceptions in execute requests raise appropriately"""
         view = self.client[-1]
         ar = view.execute("1/0")
         self.assertRaisesRemote(ZeroDivisionError, ar.get, 2)
     
     @dec.skipif_not_matplotlib
     def test_magic_pylab(self):
         """%pylab works on engines"""
         view = self.client[-1]
         ar = view.execute("%pylab inline")
         # at least check if this raised:
         reply = ar.get(5)
         # include imports, in case user config
         ar = view.execute("plot(rand(100))", silent=False)
         reply = ar.get(5)
         self.assertEqual(len(reply.outputs), 1)
         output = reply.outputs[0]
         self.assertTrue("data" in output)
         data = output['data']
         self.assertTrue("image/png" in data)
     
     def test_func_default_func(self):
         """interactively defined function as apply func default"""
         def foo():
             return 'foo'
         
         def bar(f=foo):
             return f()
         
         view = self.client[-1]
         ar = view.apply_async(bar)
         r = ar.get(10)
         self.assertEqual(r, 'foo')
     def test_data_pub_single(self):
         view = self.client[-1]
         ar = view.execute('\n'.join([
             'from IPython.zmq.datapub import publish_data',
             'for i in range(5):',
             '  publish_data(dict(i=i))'
         ]), block=False)
         self.assertTrue(isinstance(ar.data, dict))
         ar.get(5)
         self.assertEqual(ar.data, dict(i=4))
 
     def test_data_pub(self):
         view = self.client[:]
         ar = view.execute('\n'.join([
             'from IPython.zmq.datapub import publish_data',
             'for i in range(5):',
             '  publish_data(dict(i=i))'
         ]), block=False)
         self.assertTrue(all(isinstance(d, dict) for d in ar.data))
         ar.get(5)
         self.assertEqual(ar.data, [dict(i=4)] * len(ar))
     
     def test_can_list_arg(self):
         """args in lists are canned"""
         view = self.client[-1]
         view['a'] = 128
         rA = pmod.Reference('a')
         ar = view.apply_async(lambda x: x, [rA])
         r = ar.get(5)
         self.assertEqual(r, [128])
 
     def test_can_dict_arg(self):
         """args in dicts are canned"""
         view = self.client[-1]
         view['a'] = 128
         rA = pmod.Reference('a')
         ar = view.apply_async(lambda x: x, dict(foo=rA))
         r = ar.get(5)
         self.assertEqual(r, dict(foo=128))
 
     def test_can_list_kwarg(self):
         """kwargs in lists are canned"""
         view = self.client[-1]
         view['a'] = 128
         rA = pmod.Reference('a')
         ar = view.apply_async(lambda x=5: x, x=[rA])
         r = ar.get(5)
         self.assertEqual(r, [128])
 
     def test_can_dict_kwarg(self):
         """kwargs in dicts are canned"""
         view = self.client[-1]
         view['a'] = 128
         rA = pmod.Reference('a')
         ar = view.apply_async(lambda x=5: x, dict(foo=rA))
         r = ar.get(5)
         self.assertEqual(r, dict(foo=128))
     
     def test_map_ref(self):
         """view.map works with references"""
         view = self.client[:]
         ranks = sorted(self.client.ids)
         view.scatter('rank', ranks, flatten=True)
         rrank = pmod.Reference('rank')
         
         amr = view.map_async(lambda x: x*2, [rrank] * len(view))
         drank = amr.get(5)
         self.assertEqual(drank, [ r*2 for r in ranks ])
         
+    def test_nested_getitem_setitem(self):
+        """get and set with view['a.b']"""
+        view = self.client[-1]
+        view.execute('\n'.join([
+            'class A(object): pass',
+            'a = A()',
+            'a.b = 128',
+            ]), block=True)
+        ra = pmod.Reference('a')
+
+        r = view.apply_sync(lambda x: x.b, ra)
+        self.assertEqual(r, 128)
+        self.assertEqual(view['a.b'], 128)
+
+        view['a.b'] = 0
 
+        r = view.apply_sync(lambda x: x.b, ra)
+        self.assertEqual(r, 0)
+        self.assertEqual(view['a.b'], 0)

IPython/parallel/util.py

@@ -1,352 +1,355 b''
 """some generic utilities for dealing with classes, urls, and serialization
 
 Authors:
 
 * Min RK
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2010-2011  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
 #-----------------------------------------------------------------------------
 
 # Standard library imports.
 import logging
 import os
 import re
 import stat
 import socket
 import sys
 from signal import signal, SIGINT, SIGABRT, SIGTERM
 try:
     from signal import SIGKILL
 except ImportError:
     SIGKILL=None
 
 try:
     import cPickle
     pickle = cPickle
 except:
     cPickle = None
     import pickle
 
 # System library imports
 import zmq
 from zmq.log import handlers
 
 from IPython.external.decorator import decorator
 
 # IPython imports
 from IPython.config.application import Application
 from IPython.zmq.log import EnginePUBHandler
 from IPython.zmq.serialize import (
     unserialize_object, serialize_object, pack_apply_message, unpack_apply_message
 )
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 class Namespace(dict):
     """Subclass of dict for attribute access to keys."""
     
     def __getattr__(self, key):
         """getattr aliased to getitem"""
         if key in self.iterkeys():
             return self[key]
         else:
             raise NameError(key)
 
     def __setattr__(self, key, value):
         """setattr aliased to setitem, with strict"""
         if hasattr(dict, key):
             raise KeyError("Cannot override dict keys %r"%key)
         self[key] = value
     
 
 class ReverseDict(dict):
     """simple double-keyed subset of dict methods."""
     
     def __init__(self, *args, **kwargs):
         dict.__init__(self, *args, **kwargs)
         self._reverse = dict()
         for key, value in self.iteritems():
             self._reverse[value] = key
     
     def __getitem__(self, key):
         try:
             return dict.__getitem__(self, key)
         except KeyError:
             return self._reverse[key]
     
     def __setitem__(self, key, value):
         if key in self._reverse:
             raise KeyError("Can't have key %r on both sides!"%key)
         dict.__setitem__(self, key, value)
         self._reverse[value] = key
     
     def pop(self, key):
         value = dict.pop(self, key)
         self._reverse.pop(value)
         return value
     
     def get(self, key, default=None):
         try:
             return self[key]
         except KeyError:
             return default
 
 #-----------------------------------------------------------------------------
 # Functions
 #-----------------------------------------------------------------------------
 
 @decorator
 def log_errors(f, self, *args, **kwargs):
     """decorator to log unhandled exceptions raised in a method.
     
     For use wrapping on_recv callbacks, so that exceptions
     do not cause the stream to be closed.
     """
     try:
         return f(self, *args, **kwargs)
     except Exception:
         self.log.error("Uncaught exception in %r" % f, exc_info=True)
     
 
 def is_url(url):
     """boolean check for whether a string is a zmq url"""
     if '://' not in url:
         return False
     proto, addr = url.split('://', 1)
     if proto.lower() not in ['tcp','pgm','epgm','ipc','inproc']:
         return False
     return True
 
 def validate_url(url):
     """validate a url for zeromq"""
     if not isinstance(url, basestring):
         raise TypeError("url must be a string, not %r"%type(url))
     url = url.lower()
     
     proto_addr = url.split('://')
     assert len(proto_addr) == 2, 'Invalid url: %r'%url
     proto, addr = proto_addr
     assert proto in ['tcp','pgm','epgm','ipc','inproc'], "Invalid protocol: %r"%proto
     
     # domain pattern adapted from http://www.regexlib.com/REDetails.aspx?regexp_id=391
     # author: Remi Sabourin
     pat = re.compile(r'^([\w\d]([\w\d\-]{0,61}[\w\d])?\.)*[\w\d]([\w\d\-]{0,61}[\w\d])?$')
     
     if proto == 'tcp':
         lis = addr.split(':')
         assert len(lis) == 2, 'Invalid url: %r'%url
         addr,s_port = lis
         try:
             port = int(s_port)
         except ValueError:
             raise AssertionError("Invalid port %r in url: %r"%(port, url))
         
         assert addr == '*' or pat.match(addr) is not None, 'Invalid url: %r'%url
         
     else:
         # only validate tcp urls currently
         pass
     
     return True
 
 
 def validate_url_container(container):
     """validate a potentially nested collection of urls."""
     if isinstance(container, basestring):
         url = container
         return validate_url(url)
     elif isinstance(container, dict):
         container = container.itervalues()
     
     for element in container:
         validate_url_container(element)
 
 
 def split_url(url):
     """split a zmq url (tcp://ip:port) into ('tcp','ip','port')."""
     proto_addr = url.split('://')
     assert len(proto_addr) == 2, 'Invalid url: %r'%url
     proto, addr = proto_addr
     lis = addr.split(':')
     assert len(lis) == 2, 'Invalid url: %r'%url
     addr,s_port = lis
     return proto,addr,s_port
     
 def disambiguate_ip_address(ip, location=None):
     """turn multi-ip interfaces '0.0.0.0' and '*' into connectable
     ones, based on the location (default interpretation of location is localhost)."""
     if ip in ('0.0.0.0', '*'):
         try:
             external_ips = socket.gethostbyname_ex(socket.gethostname())[2]
         except (socket.gaierror, IndexError):
             # couldn't identify this machine, assume localhost
             external_ips = []
         if location is None or location in external_ips or not external_ips:
             # If location is unspecified or cannot be determined, assume local
             ip='127.0.0.1'
         elif location:
             return location
     return ip
 
 def disambiguate_url(url, location=None):
     """turn multi-ip interfaces '0.0.0.0' and '*' into connectable
     ones, based on the location (default interpretation is localhost).
     
     This is for zeromq urls, such as tcp://*:10101."""
     try:
         proto,ip,port = split_url(url)
     except AssertionError:
         # probably not tcp url; could be ipc, etc.
         return url
     
     ip = disambiguate_ip_address(ip,location)
     
     return "%s://%s:%s"%(proto,ip,port)
 
 
 #--------------------------------------------------------------------------
 # helpers for implementing old MEC API via view.apply
 #--------------------------------------------------------------------------
 
 def interactive(f):
     """decorator for making functions appear as interactively defined.
     This results in the function being linked to the user_ns as globals()
     instead of the module globals().
     """
     f.__module__ = '__main__'
     return f
 
 @interactive
 def _push(**ns):
     """helper method for implementing `client.push` via `client.apply`"""
-    globals().update(ns)
+    user_ns = globals()
+    tmp = '_IP_PUSH_TMP_'
+    while tmp in user_ns:
+        tmp = tmp + '_'
+    try:
+        for name, value in ns.iteritems():
+            user_ns[tmp] = value
+            exec "%s = %s" % (name, tmp) in user_ns
+    finally:
+        user_ns.pop(tmp, None)
 
 @interactive
 def _pull(keys):
     """helper method for implementing `client.pull` via `client.apply`"""
-    user_ns = globals()
     if isinstance(keys, (list,tuple, set)):
-        for key in keys:
-            if key not in user_ns:
-                raise NameError("name '%s' is not defined"%key)
-        return map(user_ns.get, keys)
+        return map(lambda key: eval(key, globals()), keys)
     else:
-        if keys not in user_ns:
-            raise NameError("name '%s' is not defined"%keys)
-        return user_ns.get(keys)
+        return eval(keys, globals())
 
 @interactive
 def _execute(code):
     """helper method for implementing `client.execute` via `client.apply`"""
     exec code in globals()
 
 #--------------------------------------------------------------------------
 # extra process management utilities
 #--------------------------------------------------------------------------
 
 _random_ports = set()
 
 def select_random_ports(n):
     """Selects and return n random ports that are available."""
     ports = []
     for i in xrange(n):
         sock = socket.socket()
         sock.bind(('', 0))
         while sock.getsockname()[1] in _random_ports:
             sock.close()
             sock = socket.socket()
             sock.bind(('', 0))
         ports.append(sock)
     for i, sock in enumerate(ports):
         port = sock.getsockname()[1]
         sock.close()
         ports[i] = port
         _random_ports.add(port)
     return ports
 
 def signal_children(children):
     """Relay interupt/term signals to children, for more solid process cleanup."""
     def terminate_children(sig, frame):
         log = Application.instance().log
         log.critical("Got signal %i, terminating children..."%sig)
         for child in children:
             child.terminate()
         
         sys.exit(sig != SIGINT)
         # sys.exit(sig)
     for sig in (SIGINT, SIGABRT, SIGTERM):
         signal(sig, terminate_children)
 
 def generate_exec_key(keyfile):
     import uuid
     newkey = str(uuid.uuid4())
     with open(keyfile, 'w') as f:
         # f.write('ipython-key ')
         f.write(newkey+'\n')
     # set user-only RW permissions (0600)
     # this will have no effect on Windows
     os.chmod(keyfile, stat.S_IRUSR|stat.S_IWUSR)
 
 
 def integer_loglevel(loglevel):
     try:
         loglevel = int(loglevel)
     except ValueError:
         if isinstance(loglevel, str):
             loglevel = getattr(logging, loglevel)
     return loglevel
 
 def connect_logger(logname, context, iface, root="ip", loglevel=logging.DEBUG):
     logger = logging.getLogger(logname)
     if any([isinstance(h, handlers.PUBHandler) for h in logger.handlers]):
         # don't add a second PUBHandler
         return
     loglevel = integer_loglevel(loglevel)
     lsock = context.socket(zmq.PUB)
     lsock.connect(iface)
     handler = handlers.PUBHandler(lsock)
     handler.setLevel(loglevel)
     handler.root_topic = root
     logger.addHandler(handler)
     logger.setLevel(loglevel)
 
 def connect_engine_logger(context, iface, engine, loglevel=logging.DEBUG):
     logger = logging.getLogger()
     if any([isinstance(h, handlers.PUBHandler) for h in logger.handlers]):
         # don't add a second PUBHandler
         return
     loglevel = integer_loglevel(loglevel)
     lsock = context.socket(zmq.PUB)
     lsock.connect(iface)
     handler = EnginePUBHandler(engine, lsock)
     handler.setLevel(loglevel)
     logger.addHandler(handler)
     logger.setLevel(loglevel)
     return logger
 
 def local_logger(logname, loglevel=logging.DEBUG):
     loglevel = integer_loglevel(loglevel)
     logger = logging.getLogger(logname)
     if any([isinstance(h, logging.StreamHandler) for h in logger.handlers]):
         # don't add a second StreamHandler
         return
     handler = logging.StreamHandler()
     handler.setLevel(loglevel)
     formatter = logging.Formatter("%(asctime)s.%(msecs).03d [%(name)s] %(message)s",
                 datefmt="%Y-%m-%d %H:%M:%S")
     handler.setFormatter(formatter)
 
     logger.addHandler(handler)
     logger.setLevel(loglevel)
     return logger