move default log setup to _log_default from init_logging

allows classes to be passed log attribute, avoiding duplicate setup and occasional errors if things are done in the wrong order.

IPython/config/application.py

@@ -1,508 +1,508 b''
 # encoding: utf-8
 """
 A base class for a configurable application.
 
 Authors:
 
 * Brian Granger
 * Min RK
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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 logging
 import os
 import re
 import sys
 from copy import deepcopy
 from collections import defaultdict
 
 from IPython.external.decorator import decorator
 
 from IPython.config.configurable import SingletonConfigurable
 from IPython.config.loader import (
     KVArgParseConfigLoader, PyFileConfigLoader, Config, ArgumentError, ConfigFileNotFound,
 )
 
 from IPython.utils.traitlets import (
     Unicode, List, Enum, Dict, Instance, TraitError
 )
 from IPython.utils.importstring import import_item
 from IPython.utils.text import indent, wrap_paragraphs, dedent
 
 #-----------------------------------------------------------------------------
 # function for re-wrapping a helpstring
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Descriptions for the various sections
 #-----------------------------------------------------------------------------
 
 # merge flags&aliases into options
 option_description = """
 Arguments that take values are actually convenience aliases to full
 Configurables, whose aliases are listed on the help line. For more information
 on full configurables, see '--help-all'.
 """.strip() # trim newlines of front and back
 
 keyvalue_description = """
 Parameters are set from command-line arguments of the form:
 `--Class.trait=value`.
 This line is evaluated in Python, so simple expressions are allowed, e.g.::
 `--C.a='range(3)'` For setting C.a=[0,1,2].
 """.strip() # trim newlines of front and back
 
 subcommand_description = """
 Subcommands are launched as `{app} cmd [args]`. For information on using
 subcommand 'cmd', do: `{app} cmd -h`.
 """.strip().format(app=os.path.basename(sys.argv[0]))
 # get running program name
 
 #-----------------------------------------------------------------------------
 # Application class
 #-----------------------------------------------------------------------------
 
 @decorator
 def catch_config_error(method, app, *args, **kwargs):
     """Method decorator for catching invalid config (Trait/ArgumentErrors) during init.
 
     On a TraitError (generally caused by bad config), this will print the trait's
     message, and exit the app.
     
     For use on init methods, to prevent invoking excepthook on invalid input.
     """
     try:
         return method(app, *args, **kwargs)
     except (TraitError, ArgumentError) as e:
         app.print_description()
         app.print_help()
         app.print_examples()
         app.log.fatal("Bad config encountered during initialization:")
         app.log.fatal(str(e))
         app.log.debug("Config at the time: %s", app.config)
         app.exit(1)
 
 
 class ApplicationError(Exception):
     pass
 
 
 class Application(SingletonConfigurable):
     """A singleton application with full configuration support."""
 
     # The name of the application, will usually match the name of the command
     # line application
     name = Unicode(u'application')
 
     # The description of the application that is printed at the beginning
     # of the help.
     description = Unicode(u'This is an application.')
     # default section descriptions
     option_description = Unicode(option_description)
     keyvalue_description = Unicode(keyvalue_description)
     subcommand_description = Unicode(subcommand_description)
 
     # The usage and example string that goes at the end of the help string.
     examples = Unicode()
 
     # A sequence of Configurable subclasses whose config=True attributes will
     # be exposed at the command line.
     classes = List([])
 
     # The version string of this application.
     version = Unicode(u'0.0')
 
     # The log level for the application
     log_level = Enum((0,10,20,30,40,50,'DEBUG','INFO','WARN','ERROR','CRITICAL'),
                     default_value=logging.WARN,
                     config=True,
                     help="Set the log level by value or name.")
     def _log_level_changed(self, name, old, new):
         """Adjust the log level when log_level is set."""
         if isinstance(new, basestring):
             new = getattr(logging, new)
             self.log_level = new
         self.log.setLevel(new)
+    
+    log = Instance(logging.Logger)
+    def _log_default(self):
+        """Start logging for this application.
+
+        The default is to log to stdout using a StreaHandler. The log level
+        starts at loggin.WARN, but this can be adjusted by setting the
+        ``log_level`` attribute.
+        """
+        log = logging.getLogger(self.__class__.__name__)
+        log.setLevel(self.log_level)
+        if sys.executable.endswith('pythonw.exe'):
+            # this should really go to a file, but file-logging is only
+            # hooked up in parallel applications
+            _log_handler = logging.StreamHandler(open(os.devnull, 'w'))
+        else:
+            _log_handler = logging.StreamHandler()
+        _log_formatter = logging.Formatter("[%(name)s] %(message)s")
+        _log_handler.setFormatter(_log_formatter)
+        log.addHandler(_log_handler)
+        return log
 
     # the alias map for configurables
     aliases = Dict({'log-level' : 'Application.log_level'})
 
     # flags for loading Configurables or store_const style flags
     # flags are loaded from this dict by '--key' flags
     # this must be a dict of two-tuples, the first element being the Config/dict
     # and the second being the help string for the flag
     flags = Dict()
     def _flags_changed(self, name, old, new):
         """ensure flags dict is valid"""
         for key,value in new.iteritems():
             assert len(value) == 2, "Bad flag: %r:%s"%(key,value)
             assert isinstance(value[0], (dict, Config)), "Bad flag: %r:%s"%(key,value)
             assert isinstance(value[1], basestring), "Bad flag: %r:%s"%(key,value)
 
 
     # subcommands for launching other applications
     # if this is not empty, this will be a parent Application
     # this must be a dict of two-tuples,
     # the first element being the application class/import string
     # and the second being the help string for the subcommand
     subcommands = Dict()
     # parse_command_line will initialize a subapp, if requested
     subapp = Instance('IPython.config.application.Application', allow_none=True)
 
     # extra command-line arguments that don't set config values
     extra_args = List(Unicode)
 
 
     def __init__(self, **kwargs):
         SingletonConfigurable.__init__(self, **kwargs)
         # Ensure my class is in self.classes, so my attributes appear in command line
         # options and config files.
         if self.__class__ not in self.classes:
             self.classes.insert(0, self.__class__)
 
-        self.init_logging()
-
     def _config_changed(self, name, old, new):
         SingletonConfigurable._config_changed(self, name, old, new)
         self.log.debug('Config changed:')
         self.log.debug(repr(new))
 
-    def init_logging(self):
-        """Start logging for this application.
-
-        The default is to log to stdout using a StreaHandler. The log level
-        starts at loggin.WARN, but this can be adjusted by setting the
-        ``log_level`` attribute.
-        """
-        self.log = logging.getLogger(self.__class__.__name__)
-        self.log.setLevel(self.log_level)
-        if sys.executable.endswith('pythonw.exe'):
-            # this should really go to a file, but file-logging is only
-            # hooked up in parallel applications
-            self._log_handler = logging.StreamHandler(open(os.devnull, 'w'))
-        else:
-            self._log_handler = logging.StreamHandler()
-        self._log_formatter = logging.Formatter("[%(name)s] %(message)s")
-        self._log_handler.setFormatter(self._log_formatter)
-        self.log.addHandler(self._log_handler)
-
     @catch_config_error
     def initialize(self, argv=None):
         """Do the basic steps to configure me.
 
         Override in subclasses.
         """
         self.parse_command_line(argv)
 
 
     def start(self):
         """Start the app mainloop.
 
         Override in subclasses.
         """
         if self.subapp is not None:
             return self.subapp.start()
 
     def print_alias_help(self):
         """Print the alias part of the help."""
         if not self.aliases:
             return
 
         lines = []
         classdict = {}
         for cls in self.classes:
             # include all parents (up to, but excluding Configurable) in available names
             for c in cls.mro()[:-3]:
                 classdict[c.__name__] = c
 
         for alias, longname in self.aliases.iteritems():
             classname, traitname = longname.split('.',1)
             cls = classdict[classname]
 
             trait = cls.class_traits(config=True)[traitname]
             help = cls.class_get_trait_help(trait).splitlines()
             # reformat first line
             help[0] = help[0].replace(longname, alias) + ' (%s)'%longname
             if len(alias) == 1:
                 help[0] = help[0].replace('--%s='%alias, '-%s '%alias)
             lines.extend(help)
         # lines.append('')
         print os.linesep.join(lines)
 
     def print_flag_help(self):
         """Print the flag part of the help."""
         if not self.flags:
             return
 
         lines = []
         for m, (cfg,help) in self.flags.iteritems():
             prefix = '--' if len(m) > 1 else '-'
             lines.append(prefix+m)
             lines.append(indent(dedent(help.strip())))
         # lines.append('')
         print os.linesep.join(lines)
 
     def print_options(self):
         if not self.flags and not self.aliases:
             return
         lines = ['Options']
         lines.append('-'*len(lines[0]))
         lines.append('')
         for p in wrap_paragraphs(self.option_description):
             lines.append(p)
             lines.append('')
         print os.linesep.join(lines)
         self.print_flag_help()
         self.print_alias_help()
         print
 
     def print_subcommands(self):
         """Print the subcommand part of the help."""
         if not self.subcommands:
             return
 
         lines = ["Subcommands"]
         lines.append('-'*len(lines[0]))
         lines.append('')
         for p in wrap_paragraphs(self.subcommand_description):
             lines.append(p)
             lines.append('')
         for subc, (cls, help) in self.subcommands.iteritems():
             lines.append(subc)
             if help:
                 lines.append(indent(dedent(help.strip())))
         lines.append('')
         print os.linesep.join(lines)
 
     def print_help(self, classes=False):
         """Print the help for each Configurable class in self.classes.
 
         If classes=False (the default), only flags and aliases are printed.
         """
         self.print_subcommands()
         self.print_options()
 
         if classes:
             if self.classes:
                 print "Class parameters"
                 print "----------------"
                 print
                 for p in wrap_paragraphs(self.keyvalue_description):
                     print p
                     print
 
             for cls in self.classes:
                 cls.class_print_help()
                 print
         else:
             print "To see all available configurables, use `--help-all`"
             print
 
     def print_description(self):
         """Print the application description."""
         for p in wrap_paragraphs(self.description):
             print p
             print
 
     def print_examples(self):
         """Print usage and examples.
 
         This usage string goes at the end of the command line help string
         and should contain examples of the application's usage.
         """
         if self.examples:
             print "Examples"
             print "--------"
             print
             print indent(dedent(self.examples.strip()))
             print
 
     def print_version(self):
         """Print the version string."""
         print self.version
 
     def update_config(self, config):
         """Fire the traits events when the config is updated."""
         # Save a copy of the current config.
         newconfig = deepcopy(self.config)
         # Merge the new config into the current one.
         newconfig._merge(config)
         # Save the combined config as self.config, which triggers the traits
         # events.
         self.config = newconfig
 
     @catch_config_error
     def initialize_subcommand(self, subc, argv=None):
         """Initialize a subcommand with argv."""
         subapp,help = self.subcommands.get(subc)
 
         if isinstance(subapp, basestring):
             subapp = import_item(subapp)
 
         # clear existing instances
         self.__class__.clear_instance()
         # instantiate
         self.subapp = subapp.instance()
         # and initialize subapp
         self.subapp.initialize(argv)
     
     def flatten_flags(self):
         """flatten flags and aliases, so cl-args override as expected.
         
         This prevents issues such as an alias pointing to InteractiveShell,
         but a config file setting the same trait in TerminalInteraciveShell
         getting inappropriate priority over the command-line arg.
 
         Only aliases with exactly one descendent in the class list
         will be promoted.
         
         """
         # build a tree of classes in our list that inherit from a particular
         # it will be a dict by parent classname of classes in our list
         # that are descendents
         mro_tree = defaultdict(list)
         for cls in self.classes:
             clsname = cls.__name__
             for parent in cls.mro()[1:-3]:
                 # exclude cls itself and Configurable,HasTraits,object
                 mro_tree[parent.__name__].append(clsname)
         # flatten aliases, which have the form:
         # { 'alias' : 'Class.trait' }
         aliases = {}
         for alias, cls_trait in self.aliases.iteritems():
             cls,trait = cls_trait.split('.',1)
             children = mro_tree[cls]
             if len(children) == 1:
                 # exactly one descendent, promote alias
                 cls = children[0]
             aliases[alias] = '.'.join([cls,trait])
         
         # flatten flags, which are of the form:
         # { 'key' : ({'Cls' : {'trait' : value}}, 'help')}
         flags = {}
         for key, (flagdict, help) in self.flags.iteritems():
             newflag = {}
             for cls, subdict in flagdict.iteritems():
                 children = mro_tree[cls]
                 # exactly one descendent, promote flag section
                 if len(children) == 1:
                     cls = children[0]
                 newflag[cls] = subdict
             flags[key] = (newflag, help)
         return flags, aliases
 
     @catch_config_error
     def parse_command_line(self, argv=None):
         """Parse the command line arguments."""
         argv = sys.argv[1:] if argv is None else argv
         
         if argv and argv[0] == 'help':
             # turn `ipython help notebook` into `ipython notebook -h`
             argv = argv[1:] + ['-h']
 
         if self.subcommands and len(argv) > 0:
             # we have subcommands, and one may have been specified
             subc, subargv = argv[0], argv[1:]
             if re.match(r'^\w(\-?\w)*$', subc) and subc in self.subcommands:
                 # it's a subcommand, and *not* a flag or class parameter
                 return self.initialize_subcommand(subc, subargv)
 
         if '-h' in argv or '--help' in argv or '--help-all' in argv:
             self.print_description()
             self.print_help('--help-all' in argv)
             self.print_examples()
             self.exit(0)
 
         if '--version' in argv or '-V' in argv:
             self.print_version()
             self.exit(0)
         
         # flatten flags&aliases, so cl-args get appropriate priority:
         flags,aliases = self.flatten_flags()
 
         loader = KVArgParseConfigLoader(argv=argv, aliases=aliases,
                                         flags=flags)
         config = loader.load_config()
         self.update_config(config)
         # store unparsed args in extra_args
         self.extra_args = loader.extra_args
 
     @catch_config_error
     def load_config_file(self, filename, path=None):
         """Load a .py based config file by filename and path."""
         loader = PyFileConfigLoader(filename, path=path)
         try:
             config = loader.load_config()
         except ConfigFileNotFound:
             # problem finding the file, raise
             raise
         except Exception:
             # try to get the full filename, but it will be empty in the
             # unlikely event that the error raised before filefind finished
             filename = loader.full_filename or filename
             # problem while running the file
             self.log.error("Exception while loading config file %s",
                             filename, exc_info=True)
         else:
             self.log.debug("Loaded config file: %s", loader.full_filename)
             self.update_config(config)
 
     def generate_config_file(self):
         """generate default config file from Configurables"""
         lines = ["# Configuration file for %s."%self.name]
         lines.append('')
         lines.append('c = get_config()')
         lines.append('')
         for cls in self.classes:
             lines.append(cls.class_config_section())
         return '\n'.join(lines)
 
     def exit(self, exit_status=0):
         self.log.debug("Exiting application: %s" % self.name)
         sys.exit(exit_status)
 
 #-----------------------------------------------------------------------------
 # utility functions, for convenience
 #-----------------------------------------------------------------------------
 
 def boolean_flag(name, configurable, set_help='', unset_help=''):
     """Helper for building basic --trait, --no-trait flags.
 
     Parameters
     ----------
 
     name : str
         The name of the flag.
     configurable : str
         The 'Class.trait' string of the trait to be set/unset with the flag
     set_help : unicode
         help string for --name flag
     unset_help : unicode
         help string for --no-name flag
 
     Returns
     -------
 
     cfg : dict
         A dict with two keys: 'name', and 'no-name', for setting and unsetting
         the trait, respectively.
     """
     # default helpstrings
     set_help = set_help or "set %s=True"%configurable
     unset_help = unset_help or "set %s=False"%configurable
 
     cls,trait = configurable.split('.')
 
     setter = {cls : {trait : True}}
     unsetter = {cls : {trait : False}}
     return {name : (setter, set_help), 'no-'+name : (unsetter, unset_help)}
 

IPython/frontend/html/notebook/clustermanager.py

@@ -1,174 +1,172 b''
 """Manage IPython.parallel clusters in the notebook.
 
 Authors:
 
 * Brian Granger
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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 os
 
 from tornado import web
 from zmq.eventloop import ioloop
 
 from IPython.config.configurable import LoggingConfigurable
 from IPython.config.loader import load_pyconfig_files
 from IPython.utils.traitlets import Dict, Instance, CFloat
 from IPython.parallel.apps.ipclusterapp import IPClusterStart
 from IPython.core.profileapp import list_profiles_in
 from IPython.core.profiledir import ProfileDir
 from IPython.utils.path import get_ipython_dir
 from IPython.utils.sysinfo import num_cpus
 
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 
 class DummyIPClusterStart(IPClusterStart):
     """Dummy subclass to skip init steps that conflict with global app.
     
     Instantiating and initializing this class should result in fully configured
     launchers, but no other side effects or state.
     """
 
     def init_signal(self):
         pass
-    def init_logging(self):
-        pass
     def reinit_logging(self):
         pass
 
 
 class ClusterManager(LoggingConfigurable):
 
     profiles = Dict()
 
     delay = CFloat(1., config=True,
         help="delay (in s) between starting the controller and the engines")
 
     loop = Instance('zmq.eventloop.ioloop.IOLoop')
     def _loop_default(self):
         from zmq.eventloop.ioloop import IOLoop
         return IOLoop.instance()
 
     def build_launchers(self, profile_dir):
         starter = DummyIPClusterStart(log=self.log)
         starter.initialize(['--profile-dir', profile_dir])
         cl = starter.controller_launcher
         esl = starter.engine_launcher
         n = starter.n
         return cl, esl, n
 
     def get_profile_dir(self, name, path):
         p = ProfileDir.find_profile_dir_by_name(path,name=name)
         return p.location
 
     def update_profiles(self):
         """List all profiles in the ipython_dir and cwd.
         """
         for path in [get_ipython_dir(), os.getcwdu()]:
             for profile in list_profiles_in(path):
                 pd = self.get_profile_dir(profile, path)
                 if profile not in self.profiles:
                     self.log.debug("Overwriting profile %s" % profile)
                     self.profiles[profile] = {
                         'profile': profile,
                         'profile_dir': pd,
                         'status': 'stopped'
                     }
 
     def list_profiles(self):
         self.update_profiles()
         result = [self.profile_info(p) for p in sorted(self.profiles.keys())]
         return result
 
     def check_profile(self, profile):
         if profile not in self.profiles:
             raise web.HTTPError(404, u'profile not found')
 
     def profile_info(self, profile):
         self.check_profile(profile)
         result = {}
         data = self.profiles.get(profile)
         result['profile'] = profile
         result['profile_dir'] = data['profile_dir']
         result['status'] = data['status']
         if 'n' in data:
             result['n'] = data['n']
         return result
 
     def start_cluster(self, profile, n=None):
         """Start a cluster for a given profile."""
         self.check_profile(profile)
         data = self.profiles[profile]
         if data['status'] == 'running':
             raise web.HTTPError(409, u'cluster already running')
         cl, esl, default_n = self.build_launchers(data['profile_dir'])
         n = n if n is not None else default_n
         def clean_data():
             data.pop('controller_launcher',None)
             data.pop('engine_set_launcher',None)
             data.pop('n',None)
             data['status'] = 'stopped'
         def engines_stopped(r):
             self.log.debug('Engines stopped')
             if cl.running:
                 cl.stop()
             clean_data()
         esl.on_stop(engines_stopped)
         def controller_stopped(r):
             self.log.debug('Controller stopped')
             if esl.running:
                 esl.stop()
             clean_data()
         cl.on_stop(controller_stopped)
 
         dc = ioloop.DelayedCallback(lambda: cl.start(), 0, self.loop)
         dc.start()
         dc = ioloop.DelayedCallback(lambda: esl.start(n), 1000*self.delay, self.loop)
         dc.start()
 
         self.log.debug('Cluster started')
         data['controller_launcher'] = cl
         data['engine_set_launcher'] = esl
         data['n'] = n
         data['status'] = 'running'
         return self.profile_info(profile)
 
     def stop_cluster(self, profile):
         """Stop a cluster for a given profile."""
         self.check_profile(profile)
         data = self.profiles[profile]
         if data['status'] == 'stopped':
             raise web.HTTPError(409, u'cluster not running')
         data = self.profiles[profile]
         cl = data['controller_launcher']
         esl = data['engine_set_launcher']
         if cl.running:
             cl.stop()
         if esl.running:
             esl.stop()
         # Return a temp info dict, the real one is updated in the on_stop
         # logic above.
         result = {
             'profile': data['profile'],
             'profile_dir': data['profile_dir'],
             'status': 'stopped'
         }
         return result
 
     def stop_all_clusters(self):
         for p in self.profiles.keys():
             self.stop_cluster(p)

IPython/frontend/html/notebook/notebookapp.py

@@ -1,547 +1,547 b''
 # coding: utf-8
 """A tornado based IPython notebook server.
 
 Authors:
 
 * Brian Granger
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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
 #-----------------------------------------------------------------------------
 
 # stdlib
 import errno
 import logging
 import os
 import re
 import select
 import signal
 import socket
 import sys
 import threading
 import time
 import webbrowser
 
 # Third party
 import zmq
 
 # Install the pyzmq ioloop. This has to be done before anything else from
 # tornado is imported.
 from zmq.eventloop import ioloop
 ioloop.install()
 
 from tornado import httpserver
 from tornado import web
 
 # Our own libraries
 from .kernelmanager import MappingKernelManager
 from .handlers import (LoginHandler, LogoutHandler,
     ProjectDashboardHandler, NewHandler, NamedNotebookHandler,
     MainKernelHandler, KernelHandler, KernelActionHandler, IOPubHandler,
     ShellHandler, NotebookRootHandler, NotebookHandler, NotebookCopyHandler,
     RSTHandler, AuthenticatedFileHandler, PrintNotebookHandler,
     MainClusterHandler, ClusterProfileHandler, ClusterActionHandler
 )
 from .notebookmanager import NotebookManager
 from .clustermanager import ClusterManager
 
 from IPython.config.application import catch_config_error, boolean_flag
 from IPython.core.application import BaseIPythonApplication
 from IPython.core.profiledir import ProfileDir
 from IPython.lib.kernel import swallow_argv
 from IPython.zmq.session import Session, default_secure
 from IPython.zmq.zmqshell import ZMQInteractiveShell
 from IPython.zmq.ipkernel import (
     flags as ipkernel_flags,
     aliases as ipkernel_aliases,
     IPKernelApp
 )
 from IPython.utils.traitlets import Dict, Unicode, Integer, List, Enum, Bool
 from IPython.utils import py3compat
 
 #-----------------------------------------------------------------------------
 # Module globals
 #-----------------------------------------------------------------------------
 
 _kernel_id_regex = r"(?P<kernel_id>\w+-\w+-\w+-\w+-\w+)"
 _kernel_action_regex = r"(?P<action>restart|interrupt)"
 _notebook_id_regex = r"(?P<notebook_id>\w+-\w+-\w+-\w+-\w+)"
 _profile_regex = r"(?P<profile>[a-zA-Z0-9]+)"
 _cluster_action_regex = r"(?P<action>start|stop)"
 
 
 LOCALHOST = '127.0.0.1'
 
 _examples = """
 ipython notebook                       # start the notebook
 ipython notebook --profile=sympy       # use the sympy profile
 ipython notebook --pylab=inline        # pylab in inline plotting mode
 ipython notebook --certfile=mycert.pem # use SSL/TLS certificate
 ipython notebook --port=5555 --ip=*    # Listen on port 5555, all interfaces
 """
 
 #-----------------------------------------------------------------------------
 # Helper functions
 #-----------------------------------------------------------------------------
 
 def url_path_join(a,b):
     if a.endswith('/') and b.startswith('/'):
         return a[:-1]+b
     else:
         return a+b
 
 #-----------------------------------------------------------------------------
 # The Tornado web application
 #-----------------------------------------------------------------------------
 
 class NotebookWebApplication(web.Application):
 
     def __init__(self, ipython_app, kernel_manager, notebook_manager, 
                  cluster_manager, log,
                  base_project_url, settings_overrides):
         handlers = [
             (r"/", ProjectDashboardHandler),
             (r"/login", LoginHandler),
             (r"/logout", LogoutHandler),
             (r"/new", NewHandler),
             (r"/%s" % _notebook_id_regex, NamedNotebookHandler),
             (r"/%s/copy" % _notebook_id_regex, NotebookCopyHandler),
             (r"/%s/print" % _notebook_id_regex, PrintNotebookHandler),
             (r"/kernels", MainKernelHandler),
             (r"/kernels/%s" % _kernel_id_regex, KernelHandler),
             (r"/kernels/%s/%s" % (_kernel_id_regex, _kernel_action_regex), KernelActionHandler),
             (r"/kernels/%s/iopub" % _kernel_id_regex, IOPubHandler),
             (r"/kernels/%s/shell" % _kernel_id_regex, ShellHandler),
             (r"/notebooks", NotebookRootHandler),
             (r"/notebooks/%s" % _notebook_id_regex, NotebookHandler),
             (r"/rstservice/render", RSTHandler),
             (r"/files/(.*)", AuthenticatedFileHandler, {'path' : notebook_manager.notebook_dir}),
             (r"/clusters", MainClusterHandler),
             (r"/clusters/%s/%s" % (_profile_regex, _cluster_action_regex), ClusterActionHandler),
             (r"/clusters/%s" % _profile_regex, ClusterProfileHandler),
         ]
         settings = dict(
             template_path=os.path.join(os.path.dirname(__file__), "templates"),
             static_path=os.path.join(os.path.dirname(__file__), "static"),
             cookie_secret=os.urandom(1024),
             login_url="/login",
         )
 
         # allow custom overrides for the tornado web app.
         settings.update(settings_overrides)
 
         # Python < 2.6.5 doesn't accept unicode keys in f(**kwargs), and
         # base_project_url will always be unicode, which will in turn
         # make the patterns unicode, and ultimately result in unicode
         # keys in kwargs to handler._execute(**kwargs) in tornado.
         # This enforces that base_project_url be ascii in that situation.
         # 
         # Note that the URLs these patterns check against are escaped,
         # and thus guaranteed to be ASCII: 'héllo' is really 'h%C3%A9llo'.
         base_project_url = py3compat.unicode_to_str(base_project_url, 'ascii')
         
         # prepend base_project_url onto the patterns that we match
         new_handlers = []
         for handler in handlers:
             pattern = url_path_join(base_project_url, handler[0])
             new_handler = tuple([pattern]+list(handler[1:]))
             new_handlers.append( new_handler )
 
         super(NotebookWebApplication, self).__init__(new_handlers, **settings)
 
         self.kernel_manager = kernel_manager
         self.notebook_manager = notebook_manager
         self.cluster_manager = cluster_manager
         self.ipython_app = ipython_app
         self.read_only = self.ipython_app.read_only
         self.log = log
 
 
 #-----------------------------------------------------------------------------
 # Aliases and Flags
 #-----------------------------------------------------------------------------
 
 flags = dict(ipkernel_flags)
 flags['no-browser']=(
     {'NotebookApp' : {'open_browser' : False}},
     "Don't open the notebook in a browser after startup."
 )
 flags['no-mathjax']=(
     {'NotebookApp' : {'enable_mathjax' : False}},
     """Disable MathJax
     
     MathJax is the javascript library IPython uses to render math/LaTeX. It is
     very large, so you may want to disable it if you have a slow internet
     connection, or for offline use of the notebook.
     
     When disabled, equations etc. will appear as their untransformed TeX source.
     """
 )
 flags['read-only'] = (
     {'NotebookApp' : {'read_only' : True}},
     """Allow read-only access to notebooks.
     
     When using a password to protect the notebook server, this flag
     allows unauthenticated clients to view the notebook list, and
     individual notebooks, but not edit them, start kernels, or run
     code.
     
     If no password is set, the server will be entirely read-only.
     """
 )
 
 # Add notebook manager flags
 flags.update(boolean_flag('script', 'NotebookManager.save_script',
                'Auto-save a .py script everytime the .ipynb notebook is saved',
                'Do not auto-save .py scripts for every notebook'))
 
 # the flags that are specific to the frontend
 # these must be scrubbed before being passed to the kernel,
 # or it will raise an error on unrecognized flags
 notebook_flags = ['no-browser', 'no-mathjax', 'read-only', 'script', 'no-script']
 
 aliases = dict(ipkernel_aliases)
 
 aliases.update({
     'ip': 'NotebookApp.ip',
     'port': 'NotebookApp.port',
     'keyfile': 'NotebookApp.keyfile',
     'certfile': 'NotebookApp.certfile',
     'notebook-dir': 'NotebookManager.notebook_dir',
     'browser': 'NotebookApp.browser',
 })
 
 # remove ipkernel flags that are singletons, and don't make sense in
 # multi-kernel evironment:
 aliases.pop('f', None)
 
 notebook_aliases = [u'port', u'ip', u'keyfile', u'certfile',
                     u'notebook-dir']
 
 #-----------------------------------------------------------------------------
 # NotebookApp
 #-----------------------------------------------------------------------------
 
 class NotebookApp(BaseIPythonApplication):
 
     name = 'ipython-notebook'
     default_config_file_name='ipython_notebook_config.py'
     
     description = """
         The IPython HTML Notebook.
         
         This launches a Tornado based HTML Notebook Server that serves up an
         HTML5/Javascript Notebook client.
     """
     examples = _examples
     
     classes = [IPKernelApp, ZMQInteractiveShell, ProfileDir, Session,
                MappingKernelManager, NotebookManager]
     flags = Dict(flags)
     aliases = Dict(aliases)
 
     kernel_argv = List(Unicode)
 
     log_level = Enum((0,10,20,30,40,50,'DEBUG','INFO','WARN','ERROR','CRITICAL'),
                     default_value=logging.INFO,
                     config=True,
                     help="Set the log level by value or name.")
 
     # create requested profiles by default, if they don't exist:
     auto_create = Bool(True)
 
     # Network related information.
 
     ip = Unicode(LOCALHOST, config=True,
         help="The IP address the notebook server will listen on."
     )
 
     def _ip_changed(self, name, old, new):
         if new == u'*': self.ip = u''
 
     port = Integer(8888, config=True,
         help="The port the notebook server will listen on."
     )
 
     certfile = Unicode(u'', config=True, 
         help="""The full path to an SSL/TLS certificate file."""
     )
     
     keyfile = Unicode(u'', config=True, 
         help="""The full path to a private key file for usage with SSL/TLS."""
     )
 
     password = Unicode(u'', config=True,
                       help="""Hashed password to use for web authentication.
 
                       To generate, type in a python/IPython shell:
 
                         from IPython.lib import passwd; passwd()
 
                       The string should be of the form type:salt:hashed-password.
                       """
     )
 
     open_browser = Bool(True, config=True,
                         help="""Whether to open in a browser after starting.
                         The specific browser used is platform dependent and
                         determined by the python standard library `webbrowser`
                         module, unless it is overridden using the --browser
                         (NotebookApp.browser) configuration option.
                         """)
 
     browser = Unicode(u'', config=True,
                       help="""Specify what command to use to invoke a web
                       browser when opening the notebook. If not specified, the
                       default browser will be determined by the `webbrowser`
                       standard library module, which allows setting of the
                       BROWSER environment variable to override it.
                       """)
     
     read_only = Bool(False, config=True,
         help="Whether to prevent editing/execution of notebooks."
     )
     
     webapp_settings = Dict(config=True,
             help="Supply overrides for the tornado.web.Application that the "
                  "IPython notebook uses.")
     
     enable_mathjax = Bool(True, config=True,
         help="""Whether to enable MathJax for typesetting math/TeX
 
         MathJax is the javascript library IPython uses to render math/LaTeX. It is
         very large, so you may want to disable it if you have a slow internet
         connection, or for offline use of the notebook.
 
         When disabled, equations etc. will appear as their untransformed TeX source.
         """
     )
     def _enable_mathjax_changed(self, name, old, new):
         """set mathjax url to empty if mathjax is disabled"""
         if not new:
             self.mathjax_url = u''
 
     base_project_url = Unicode('/', config=True,
                                help='''The base URL for the notebook server''')
     base_kernel_url = Unicode('/', config=True,
                                help='''The base URL for the kernel server''')
     websocket_host = Unicode("", config=True,
         help="""The hostname for the websocket server."""
     )
 
     mathjax_url = Unicode("", config=True,
         help="""The url for MathJax.js."""
     )
     def _mathjax_url_default(self):
         if not self.enable_mathjax:
             return u''
         static_path = self.webapp_settings.get("static_path", os.path.join(os.path.dirname(__file__), "static"))
         static_url_prefix = self.webapp_settings.get("static_url_prefix",
                                                      "/static/")
         if os.path.exists(os.path.join(static_path, 'mathjax', "MathJax.js")):
             self.log.info("Using local MathJax")
             return static_url_prefix+u"mathjax/MathJax.js"
         else:
             if self.certfile:
                 # HTTPS: load from Rackspace CDN, because SSL certificate requires it
                 base = u"https://c328740.ssl.cf1.rackcdn.com"
             else:
                 base = u"http://cdn.mathjax.org"
             
             url = base + u"/mathjax/latest/MathJax.js"
             self.log.info("Using MathJax from CDN: %s", url)
             return url
     
     def _mathjax_url_changed(self, name, old, new):
         if new and not self.enable_mathjax:
             # enable_mathjax=False overrides mathjax_url
             self.mathjax_url = u''
         else:
             self.log.info("Using MathJax: %s", new)
 
     def parse_command_line(self, argv=None):
         super(NotebookApp, self).parse_command_line(argv)
         if argv is None:
             argv = sys.argv[1:]
 
         # Scrub frontend-specific flags
         self.kernel_argv = swallow_argv(argv, notebook_aliases, notebook_flags)
         # Kernel should inherit default config file from frontend
         self.kernel_argv.append("--KernelApp.parent_appname='%s'"%self.name)
 
     def init_configurables(self):
         # force Session default to be secure
         default_secure(self.config)
         # Create a KernelManager and start a kernel.
         self.kernel_manager = MappingKernelManager(
             config=self.config, log=self.log, kernel_argv=self.kernel_argv,
             connection_dir = self.profile_dir.security_dir,
         )
         self.notebook_manager = NotebookManager(config=self.config, log=self.log)
         self.notebook_manager.list_notebooks()
         self.cluster_manager = ClusterManager(config=self.config, log=self.log)
         self.cluster_manager.update_profiles()
 
     def init_logging(self):
-        super(NotebookApp, self).init_logging()
         # This prevents double log messages because tornado use a root logger that
         # self.log is a child of. The logging module dipatches log messages to a log
         # and all of its ancenstors until propagate is set to False.
         self.log.propagate = False
     
     def init_webapp(self):
         """initialize tornado webapp and httpserver"""
         self.web_app = NotebookWebApplication(
             self, self.kernel_manager, self.notebook_manager, 
             self.cluster_manager, self.log,
             self.base_project_url, self.webapp_settings
         )
         if self.certfile:
             ssl_options = dict(certfile=self.certfile)
             if self.keyfile:
                 ssl_options['keyfile'] = self.keyfile
         else:
             ssl_options = None
         self.web_app.password = self.password
         self.http_server = httpserver.HTTPServer(self.web_app, ssl_options=ssl_options)
         if ssl_options is None and not self.ip and not (self.read_only and not self.password):
             self.log.critical('WARNING: the notebook server is listening on all IP addresses '
                               'but not using any encryption or authentication. This is highly '
                               'insecure and not recommended.')
 
         # Try random ports centered around the default.
         from random import randint
         n = 50  # Max number of attempts, keep reasonably large.
         for port in range(self.port, self.port+5) + [self.port + randint(-2*n, 2*n) for i in range(n-5)]:
             try:
                 self.http_server.listen(port, self.ip)
             except socket.error, e:
                 if e.errno != errno.EADDRINUSE:
                     raise
                 self.log.info('The port %i is already in use, trying another random port.' % port)
             else:
                 self.port = port
                 break
     
     def init_signal(self):
         # FIXME: remove this check when pyzmq dependency is >= 2.1.11
         # safely extract zmq version info:
         try:
             zmq_v = zmq.pyzmq_version_info()
         except AttributeError:
             zmq_v = [ int(n) for n in re.findall(r'\d+', zmq.__version__) ]
             if 'dev' in zmq.__version__:
                 zmq_v.append(999)
             zmq_v = tuple(zmq_v)
         if zmq_v >= (2,1,9):
             # This won't work with 2.1.7 and
             # 2.1.9-10 will log ugly 'Interrupted system call' messages,
             # but it will work
             signal.signal(signal.SIGINT, self._handle_sigint)
         signal.signal(signal.SIGTERM, self._signal_stop)
     
     def _handle_sigint(self, sig, frame):
         """SIGINT handler spawns confirmation dialog"""
         # register more forceful signal handler for ^C^C case
         signal.signal(signal.SIGINT, self._signal_stop)
         # request confirmation dialog in bg thread, to avoid
         # blocking the App
         thread = threading.Thread(target=self._confirm_exit)
         thread.daemon = True
         thread.start()
     
     def _restore_sigint_handler(self):
         """callback for restoring original SIGINT handler"""
         signal.signal(signal.SIGINT, self._handle_sigint)
     
     def _confirm_exit(self):
         """confirm shutdown on ^C
         
         A second ^C, or answering 'y' within 5s will cause shutdown,
         otherwise original SIGINT handler will be restored.
         """
         # FIXME: remove this delay when pyzmq dependency is >= 2.1.11
         time.sleep(0.1)
         sys.stdout.write("Shutdown Notebook Server (y/[n])? ")
         sys.stdout.flush()
         r,w,x = select.select([sys.stdin], [], [], 5)
         if r:
             line = sys.stdin.readline()
             if line.lower().startswith('y'):
                 self.log.critical("Shutdown confirmed")
                 ioloop.IOLoop.instance().stop()
                 return
         else:
             print "No answer for 5s:",
         print "resuming operation..."
         # no answer, or answer is no:
         # set it back to original SIGINT handler
         # use IOLoop.add_callback because signal.signal must be called
         # from main thread
         ioloop.IOLoop.instance().add_callback(self._restore_sigint_handler)
     
     def _signal_stop(self, sig, frame):
         self.log.critical("received signal %s, stopping", sig)
         ioloop.IOLoop.instance().stop()
     
     @catch_config_error
     def initialize(self, argv=None):
+        self.init_logging()
         super(NotebookApp, self).initialize(argv)
         self.init_configurables()
         self.init_webapp()
         self.init_signal()
 
     def cleanup_kernels(self):
         """shutdown all kernels
         
         The kernels will shutdown themselves when this process no longer exists,
         but explicit shutdown allows the KernelManagers to cleanup the connection files.
         """
         self.log.info('Shutting down kernels')
         km = self.kernel_manager
         # copy list, since kill_kernel deletes keys
         for kid in list(km.kernel_ids):
             km.kill_kernel(kid)
 
     def start(self):
         ip = self.ip if self.ip else '[all ip addresses on your system]'
         proto = 'https' if self.certfile else 'http'
         info = self.log.info
         info("The IPython Notebook is running at: %s://%s:%i%s" %
              (proto, ip, self.port,self.base_project_url) )
         info("Use Control-C to stop this server and shut down all kernels.")
 
         if self.open_browser:
             ip = self.ip or '127.0.0.1'
             if self.browser:
                 browser = webbrowser.get(self.browser)
             else:
                 browser = webbrowser.get()
             b = lambda : browser.open("%s://%s:%i%s" % (proto, ip, self.port,
                                                            self.base_project_url),
                                          new=2)
             threading.Thread(target=b).start()
         try:
             ioloop.IOLoop.instance().start()
         except KeyboardInterrupt:
             info("Interrupted...")
         finally:
             self.cleanup_kernels()
     
 
 #-----------------------------------------------------------------------------
 # Main entry point
 #-----------------------------------------------------------------------------
 
 def launch_new_instance():
     app = NotebookApp.instance()
     app.initialize()
     app.start()
 

IPython/parallel/apps/baseapp.py

@@ -1,265 +1,268 b''
 # encoding: utf-8
 """
 The Base Application class for IPython.parallel apps
 
 Authors:
 
 * Brian Granger
 * Min RK
 
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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 __future__ import with_statement
 
 import os
 import logging
 import re
 import sys
 
 from subprocess import Popen, PIPE
 
 from IPython.config.application import catch_config_error
 from IPython.core import release
 from IPython.core.crashhandler import CrashHandler
 from IPython.core.application import (
     BaseIPythonApplication,
     base_aliases as base_ip_aliases,
     base_flags as base_ip_flags
 )
 from IPython.utils.path import expand_path
 
 from IPython.utils.traitlets import Unicode, Bool, Instance, Dict, List
 
 #-----------------------------------------------------------------------------
 # Module errors
 #-----------------------------------------------------------------------------
 
 class PIDFileError(Exception):
     pass
 
 
 #-----------------------------------------------------------------------------
 # Crash handler for this application
 #-----------------------------------------------------------------------------
 
 class ParallelCrashHandler(CrashHandler):
     """sys.excepthook for IPython itself, leaves a detailed report on disk."""
 
     def __init__(self, app):
         contact_name = release.authors['Min'][0]
         contact_email = release.author_email
         bug_tracker = 'https://github.com/ipython/ipython/issues'
         super(ParallelCrashHandler,self).__init__(
             app, contact_name, contact_email, bug_tracker
         )
 
 
 #-----------------------------------------------------------------------------
 # Main application
 #-----------------------------------------------------------------------------
 base_aliases = {}
 base_aliases.update(base_ip_aliases)
 base_aliases.update({
     'profile-dir' : 'ProfileDir.location',
     'work-dir' : 'BaseParallelApplication.work_dir',
     'log-to-file' : 'BaseParallelApplication.log_to_file',
     'clean-logs' : 'BaseParallelApplication.clean_logs',
     'log-url' : 'BaseParallelApplication.log_url',
     'cluster-id' : 'BaseParallelApplication.cluster_id',
 })
 
 base_flags = {
     'log-to-file' : (
         {'BaseParallelApplication' : {'log_to_file' : True}},
         "send log output to a file"
     )
 }
 base_flags.update(base_ip_flags)
 
 class BaseParallelApplication(BaseIPythonApplication):
     """The base Application for IPython.parallel apps
     
     Principle extensions to BaseIPyythonApplication:
     
     * work_dir
     * remote logging via pyzmq
     * IOLoop instance
     """
 
     crash_handler_class = ParallelCrashHandler
     
     def _log_level_default(self):
         # temporarily override default_log_level to INFO
         return logging.INFO
 
     work_dir = Unicode(os.getcwdu(), config=True,
         help='Set the working dir for the process.'
     )
     def _work_dir_changed(self, name, old, new):
         self.work_dir = unicode(expand_path(new))
 
     log_to_file = Bool(config=True,
         help="whether to log to a file")
 
     clean_logs = Bool(False, config=True,
         help="whether to cleanup old logfiles before starting")
 
     log_url = Unicode('', config=True,
         help="The ZMQ URL of the iplogger to aggregate logging.")
 
     cluster_id = Unicode('', config=True,
         help="""String id to add to runtime files, to prevent name collisions when
         using multiple clusters with a single profile simultaneously.
         
         When set, files will be named like: 'ipcontroller-<cluster_id>-engine.json'
         
         Since this is text inserted into filenames, typical recommendations apply:
         Simple character strings are ideal, and spaces are not recommended (but should
         generally work).
         """
     )
     def _cluster_id_changed(self, name, old, new):
         self.name = self.__class__.name
         if new:
             self.name += '-%s'%new
     
     def _config_files_default(self):
         return ['ipcontroller_config.py', 'ipengine_config.py', 'ipcluster_config.py']
     
     loop = Instance('zmq.eventloop.ioloop.IOLoop')
     def _loop_default(self):
         from zmq.eventloop.ioloop import IOLoop
         return IOLoop.instance()
 
     aliases = Dict(base_aliases)
     flags = Dict(base_flags)
     
     @catch_config_error
     def initialize(self, argv=None):
         """initialize the app"""
         super(BaseParallelApplication, self).initialize(argv)
         self.to_work_dir()
         self.reinit_logging()
         
     def to_work_dir(self):
         wd = self.work_dir
         if unicode(wd) != os.getcwdu():
             os.chdir(wd)
             self.log.info("Changing to working dir: %s" % wd)
         # This is the working dir by now.
         sys.path.insert(0, '')
 
     def reinit_logging(self):
         # Remove old log files
         log_dir = self.profile_dir.log_dir
         if self.clean_logs:
             for f in os.listdir(log_dir):
                 if re.match(r'%s-\d+\.(log|err|out)'%self.name,f):
                     os.remove(os.path.join(log_dir, f))
         if self.log_to_file:
             # Start logging to the new log file
             log_filename = self.name + u'-' + str(os.getpid()) + u'.log'
             logfile = os.path.join(log_dir, log_filename)
             open_log_file = open(logfile, 'w')
         else:
             open_log_file = None
         if open_log_file is not None:
-            self.log.removeHandler(self._log_handler)
+            while self.log.handlers:
+                self.log.removeHandler(self.log.handlers[0])
             self._log_handler = logging.StreamHandler(open_log_file)
             self.log.addHandler(self._log_handler)
+        else:
+            self._log_handler = self.log.handlers[0]
         # Add timestamps to log format:
         self._log_formatter = logging.Formatter("%(asctime)s.%(msecs).03d [%(name)s] %(message)s",
                                                 datefmt="%Y-%m-%d %H:%M:%S")
         self._log_handler.setFormatter(self._log_formatter)
         # do not propagate log messages to root logger
         # ipcluster app will sometimes print duplicate messages during shutdown
         # if this is 1 (default):
         self.log.propagate = False
 
     def write_pid_file(self, overwrite=False):
         """Create a .pid file in the pid_dir with my pid.
 
         This must be called after pre_construct, which sets `self.pid_dir`.
         This raises :exc:`PIDFileError` if the pid file exists already.
         """
         pid_file = os.path.join(self.profile_dir.pid_dir, self.name + u'.pid')
         if os.path.isfile(pid_file):
             pid = self.get_pid_from_file()
             if not overwrite:
                 raise PIDFileError(
                     'The pid file [%s] already exists. \nThis could mean that this '
                     'server is already running with [pid=%s].' % (pid_file, pid)
                 )
         with open(pid_file, 'w') as f:
             self.log.info("Creating pid file: %s" % pid_file)
             f.write(repr(os.getpid())+'\n')
 
     def remove_pid_file(self):
         """Remove the pid file.
 
         This should be called at shutdown by registering a callback with
         :func:`reactor.addSystemEventTrigger`. This needs to return
         ``None``.
         """
         pid_file = os.path.join(self.profile_dir.pid_dir, self.name + u'.pid')
         if os.path.isfile(pid_file):
             try:
                 self.log.info("Removing pid file: %s" % pid_file)
                 os.remove(pid_file)
             except:
                 self.log.warn("Error removing the pid file: %s" % pid_file)
 
     def get_pid_from_file(self):
         """Get the pid from the pid file.
 
         If the  pid file doesn't exist a :exc:`PIDFileError` is raised.
         """
         pid_file = os.path.join(self.profile_dir.pid_dir, self.name + u'.pid')
         if os.path.isfile(pid_file):
             with open(pid_file, 'r') as f:
                 s = f.read().strip()
                 try:
                     pid = int(s)
                 except:
                     raise PIDFileError("invalid pid file: %s (contents: %r)"%(pid_file, s))
                 return pid
         else:
             raise PIDFileError('pid file not found: %s' % pid_file)
     
     def check_pid(self, pid):
         if os.name == 'nt':
             try:
                 import ctypes
                 # returns 0 if no such process (of ours) exists
                 # positive int otherwise
                 p = ctypes.windll.kernel32.OpenProcess(1,0,pid)
             except Exception:
                 self.log.warn(
                     "Could not determine whether pid %i is running via `OpenProcess`. "
                     " Making the likely assumption that it is."%pid
                 )
                 return True
             return bool(p)
         else:
             try:
                 p = Popen(['ps','x'], stdout=PIPE, stderr=PIPE)
                 output,_ = p.communicate()
             except OSError:
                 self.log.warn(
                     "Could not determine whether pid %i is running via `ps x`. "
                     " Making the likely assumption that it is."%pid
                 )
                 return True
             pids = map(int, re.findall(r'^\W*\d+', output, re.MULTILINE))
             return pid in pids

IPython/parallel/apps/ipcontrollerapp.py

@@ -1,493 +1,491 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 The IPython controller application.
 
 Authors:
 
 * Brian Granger
 * MinRK
 
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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 __future__ import with_statement
 
 import json
 import os
 import socket
 import stat
 import sys
 
 from multiprocessing import Process
 from signal import signal, SIGINT, SIGABRT, SIGTERM
 
 import zmq
 from zmq.devices import ProcessMonitoredQueue
 from zmq.log.handlers import PUBHandler
 
 from IPython.core.profiledir import ProfileDir
 
 from IPython.parallel.apps.baseapp import (
     BaseParallelApplication,
     base_aliases,
     base_flags,
     catch_config_error,
 )
 from IPython.utils.importstring import import_item
 from IPython.utils.traitlets import Instance, Unicode, Bool, List, Dict, TraitError
 
 from IPython.zmq.session import (
     Session, session_aliases, session_flags, default_secure
 )
 
 from IPython.parallel.controller.heartmonitor import HeartMonitor
 from IPython.parallel.controller.hub import HubFactory
 from IPython.parallel.controller.scheduler import TaskScheduler,launch_scheduler
 from IPython.parallel.controller.sqlitedb import SQLiteDB
 
 from IPython.parallel.util import split_url, disambiguate_url
 
 # conditional import of MongoDB backend class
 
 try:
     from IPython.parallel.controller.mongodb import MongoDB
 except ImportError:
     maybe_mongo = []
 else:
     maybe_mongo = [MongoDB]
 
 
 #-----------------------------------------------------------------------------
 # Module level variables
 #-----------------------------------------------------------------------------
 
 
 #: The default config file name for this application
 default_config_file_name = u'ipcontroller_config.py'
 
 
 _description = """Start the IPython controller for parallel computing.
 
 The IPython controller provides a gateway between the IPython engines and
 clients. The controller needs to be started before the engines and can be
 configured using command line options or using a cluster directory. Cluster
 directories contain config, log and security files and are usually located in
 your ipython directory and named as "profile_name". See the `profile`
 and `profile-dir` options for details.
 """
 
 _examples = """
 ipcontroller --ip=192.168.0.1 --port=1000  # listen on ip, port for engines
 ipcontroller --scheme=pure  # use the pure zeromq scheduler
 """
 
 
 #-----------------------------------------------------------------------------
 # The main application
 #-----------------------------------------------------------------------------
 flags = {}
 flags.update(base_flags)
 flags.update({
     'usethreads' : ( {'IPControllerApp' : {'use_threads' : True}},
                     'Use threads instead of processes for the schedulers'),
     'sqlitedb' : ({'HubFactory' : {'db_class' : 'IPython.parallel.controller.sqlitedb.SQLiteDB'}},
                     'use the SQLiteDB backend'),
     'mongodb' : ({'HubFactory' : {'db_class' : 'IPython.parallel.controller.mongodb.MongoDB'}},
                     'use the MongoDB backend'),
     'dictdb' : ({'HubFactory' : {'db_class' : 'IPython.parallel.controller.dictdb.DictDB'}},
                     'use the in-memory DictDB backend'),
     'nodb' : ({'HubFactory' : {'db_class' : 'IPython.parallel.controller.dictdb.NoDB'}},
                     """use dummy DB backend, which doesn't store any information.
                     
                     This can be used to prevent growth of the memory footprint of the Hub
                     in cases where its record-keeping is not required.  Requesting results
                     of tasks submitted by other clients, db_queries, and task resubmission
                     will not be available."""),
     'reuse' : ({'IPControllerApp' : {'reuse_files' : True}},
                     'reuse existing json connection files')
 })
 
 flags.update(session_flags)
 
 aliases = dict(
     ssh = 'IPControllerApp.ssh_server',
     enginessh = 'IPControllerApp.engine_ssh_server',
     location = 'IPControllerApp.location',
 
     url = 'HubFactory.url',
     ip = 'HubFactory.ip',
     transport = 'HubFactory.transport',
     port = 'HubFactory.regport',
 
     ping = 'HeartMonitor.period',
 
     scheme = 'TaskScheduler.scheme_name',
     hwm = 'TaskScheduler.hwm',
 )
 aliases.update(base_aliases)
 aliases.update(session_aliases)
 
 
 class IPControllerApp(BaseParallelApplication):
 
     name = u'ipcontroller'
     description = _description
     examples = _examples
     config_file_name = Unicode(default_config_file_name)
     classes = [ProfileDir, Session, HubFactory, TaskScheduler, HeartMonitor, SQLiteDB] + maybe_mongo
     
     # change default to True
     auto_create = Bool(True, config=True,
         help="""Whether to create profile dir if it doesn't exist.""")
     
     reuse_files = Bool(False, config=True,
         help="""Whether to reuse existing json connection files.
         If False, connection files will be removed on a clean exit.
         """
     )
     ssh_server = Unicode(u'', config=True,
         help="""ssh url for clients to use when connecting to the Controller
         processes. It should be of the form: [user@]server[:port]. The
         Controller's listening addresses must be accessible from the ssh server""",
     )
     engine_ssh_server = Unicode(u'', config=True,
         help="""ssh url for engines to use when connecting to the Controller
         processes. It should be of the form: [user@]server[:port]. The
         Controller's listening addresses must be accessible from the ssh server""",
     )
     location = Unicode(u'', config=True,
         help="""The external IP or domain name of the Controller, used for disambiguating
         engine and client connections.""",
     )
     import_statements = List([], config=True,
         help="import statements to be run at startup.  Necessary in some environments"
     )
 
     use_threads = Bool(False, config=True,
         help='Use threads instead of processes for the schedulers',
     )
 
     engine_json_file = Unicode('ipcontroller-engine.json', config=True,
         help="JSON filename where engine connection info will be stored.")
     client_json_file = Unicode('ipcontroller-client.json', config=True,
         help="JSON filename where client connection info will be stored.")
     
     def _cluster_id_changed(self, name, old, new):
         super(IPControllerApp, self)._cluster_id_changed(name, old, new)
         self.engine_json_file = "%s-engine.json" % self.name
         self.client_json_file = "%s-client.json" % self.name
 
 
     # internal
     children = List()
     mq_class = Unicode('zmq.devices.ProcessMonitoredQueue')
 
     def _use_threads_changed(self, name, old, new):
         self.mq_class = 'zmq.devices.%sMonitoredQueue'%('Thread' if new else 'Process')
     
     write_connection_files = Bool(True,
         help="""Whether to write connection files to disk.
         True in all cases other than runs with `reuse_files=True` *after the first*
         """
     )
 
     aliases = Dict(aliases)
     flags = Dict(flags)
     
 
     def save_connection_dict(self, fname, cdict):
         """save a connection dict to json file."""
         c = self.config
         url = cdict['url']
         location = cdict['location']
         if not location:
             try:
                 proto,ip,port = split_url(url)
             except AssertionError:
                 pass
             else:
                 try:
                     location = socket.gethostbyname_ex(socket.gethostname())[2][-1]
                 except (socket.gaierror, IndexError):
                     self.log.warn("Could not identify this machine's IP, assuming 127.0.0.1."
                     " You may need to specify '--location=<external_ip_address>' to help"
                     " IPython decide when to connect via loopback.")
                     location = '127.0.0.1'
             cdict['location'] = location
         fname = os.path.join(self.profile_dir.security_dir, fname)
         self.log.info("writing connection info to %s", fname)
         with open(fname, 'w') as f:
             f.write(json.dumps(cdict, indent=2))
         os.chmod(fname, stat.S_IRUSR|stat.S_IWUSR)
     
     def load_config_from_json(self):
         """load config from existing json connector files."""
         c = self.config
         self.log.debug("loading config from JSON")
         # load from engine config
         fname = os.path.join(self.profile_dir.security_dir, self.engine_json_file)
         self.log.info("loading connection info from %s", fname)
         with open(fname) as f:
             cfg = json.loads(f.read())
         key = cfg['exec_key']
         # json gives unicode, Session.key wants bytes
         c.Session.key = key.encode('ascii')
         xport,addr = cfg['url'].split('://')
         c.HubFactory.engine_transport = xport
         ip,ports = addr.split(':')
         c.HubFactory.engine_ip = ip
         c.HubFactory.regport = int(ports)
         self.location = cfg['location']
         if not self.engine_ssh_server:
             self.engine_ssh_server = cfg['ssh']
         # load client config
         fname = os.path.join(self.profile_dir.security_dir, self.client_json_file)
         self.log.info("loading connection info from %s", fname)
         with open(fname) as f:
             cfg = json.loads(f.read())
         assert key == cfg['exec_key'], "exec_key mismatch between engine and client keys"
         xport,addr = cfg['url'].split('://')
         c.HubFactory.client_transport = xport
         ip,ports = addr.split(':')
         c.HubFactory.client_ip = ip
         if not self.ssh_server:
             self.ssh_server = cfg['ssh']
         assert int(ports) == c.HubFactory.regport, "regport mismatch"
     
     def cleanup_connection_files(self):
         if self.reuse_files:
             self.log.debug("leaving JSON connection files for reuse")
             return
         self.log.debug("cleaning up JSON connection files")
         for f in (self.client_json_file, self.engine_json_file):
             f = os.path.join(self.profile_dir.security_dir, f)
             try:
                 os.remove(f)
             except Exception as e:
                 self.log.error("Failed to cleanup connection file: %s", e)
             else:
                 self.log.debug(u"removed %s", f)
     
     def load_secondary_config(self):
         """secondary config, loading from JSON and setting defaults"""
         if self.reuse_files:
             try:
                 self.load_config_from_json()
             except (AssertionError,IOError) as e:
                 self.log.error("Could not load config from JSON: %s" % e)
             else:
                 # successfully loaded config from JSON, and reuse=True
                 # no need to wite back the same file
                 self.write_connection_files = False
                 
         # switch Session.key default to secure
         default_secure(self.config)
         self.log.debug("Config changed")
         self.log.debug(repr(self.config))
         
     def init_hub(self):
         c = self.config
         
         self.do_import_statements()
         
         try:
             self.factory = HubFactory(config=c, log=self.log)
             # self.start_logging()
             self.factory.init_hub()
         except TraitError:
             raise
         except Exception:
             self.log.error("Couldn't construct the Controller", exc_info=True)
             self.exit(1)
         
         if self.write_connection_files:
             # save to new json config files
             f = self.factory
             cdict = {'exec_key' : f.session.key.decode('ascii'),
                     'ssh' : self.ssh_server,
                     'url' : "%s://%s:%s"%(f.client_transport, f.client_ip, f.regport),
                     'location' : self.location
                     }
             self.save_connection_dict(self.client_json_file, cdict)
             edict = cdict
             edict['url']="%s://%s:%s"%((f.client_transport, f.client_ip, f.regport))
             edict['ssh'] = self.engine_ssh_server
             self.save_connection_dict(self.engine_json_file, edict)
 
     def init_schedulers(self):
         children = self.children
         mq = import_item(str(self.mq_class))
         
         hub = self.factory
         # disambiguate url, in case of *
         monitor_url = disambiguate_url(hub.monitor_url)
         # maybe_inproc = 'inproc://monitor' if self.use_threads else monitor_url
         # IOPub relay (in a Process)
         q = mq(zmq.PUB, zmq.SUB, zmq.PUB, b'N/A',b'iopub')
         q.bind_in(hub.client_info['iopub'])
         q.bind_out(hub.engine_info['iopub'])
         q.setsockopt_out(zmq.SUBSCRIBE, b'')
         q.connect_mon(monitor_url)
         q.daemon=True
         children.append(q)
 
         # Multiplexer Queue (in a Process)
         q = mq(zmq.ROUTER, zmq.ROUTER, zmq.PUB, b'in', b'out')
         q.bind_in(hub.client_info['mux'])
         q.setsockopt_in(zmq.IDENTITY, b'mux')
         q.bind_out(hub.engine_info['mux'])
         q.connect_mon(monitor_url)
         q.daemon=True
         children.append(q)
 
         # Control Queue (in a Process)
         q = mq(zmq.ROUTER, zmq.ROUTER, zmq.PUB, b'incontrol', b'outcontrol')
         q.bind_in(hub.client_info['control'])
         q.setsockopt_in(zmq.IDENTITY, b'control')
         q.bind_out(hub.engine_info['control'])
         q.connect_mon(monitor_url)
         q.daemon=True
         children.append(q)
         try:
             scheme = self.config.TaskScheduler.scheme_name
         except AttributeError:
             scheme = TaskScheduler.scheme_name.get_default_value()
         # Task Queue (in a Process)
         if scheme == 'pure':
             self.log.warn("task::using pure XREQ Task scheduler")
             q = mq(zmq.ROUTER, zmq.DEALER, zmq.PUB, b'intask', b'outtask')
             # q.setsockopt_out(zmq.HWM, hub.hwm)
             q.bind_in(hub.client_info['task'][1])
             q.setsockopt_in(zmq.IDENTITY, b'task')
             q.bind_out(hub.engine_info['task'])
             q.connect_mon(monitor_url)
             q.daemon=True
             children.append(q)
         elif scheme == 'none':
             self.log.warn("task::using no Task scheduler")
 
         else:
             self.log.info("task::using Python %s Task scheduler"%scheme)
             sargs = (hub.client_info['task'][1], hub.engine_info['task'],
                                 monitor_url, disambiguate_url(hub.client_info['notification']))
             kwargs = dict(logname='scheduler', loglevel=self.log_level,
                             log_url = self.log_url, config=dict(self.config))
             if 'Process' in self.mq_class:
                 # run the Python scheduler in a Process
                 q = Process(target=launch_scheduler, args=sargs, kwargs=kwargs)
                 q.daemon=True
                 children.append(q)
             else:
                 # single-threaded Controller
                 kwargs['in_thread'] = True
                 launch_scheduler(*sargs, **kwargs)
 
     def terminate_children(self):
         child_procs = []
         for child in self.children:
             if isinstance(child, ProcessMonitoredQueue):
                 child_procs.append(child.launcher)
             elif isinstance(child, Process):
                 child_procs.append(child)
         if child_procs:
             self.log.critical("terminating children...")
             for child in child_procs:
                 try:
                     child.terminate()
                 except OSError:
                     # already dead
                     pass
     
     def handle_signal(self, sig, frame):
         self.log.critical("Received signal %i, shutting down", sig)
         self.terminate_children()
         self.loop.stop()
     
     def init_signal(self):
         for sig in (SIGINT, SIGABRT, SIGTERM):
             signal(sig, self.handle_signal)
 
     def do_import_statements(self):
         statements = self.import_statements
         for s in statements:
             try:
                 self.log.msg("Executing statement: '%s'" % s)
                 exec s in globals(), locals()
             except:
                 self.log.msg("Error running statement: %s" % s)
 
     def forward_logging(self):
         if self.log_url:
             self.log.info("Forwarding logging to %s"%self.log_url)
             context = zmq.Context.instance()
             lsock = context.socket(zmq.PUB)
             lsock.connect(self.log_url)
             handler = PUBHandler(lsock)
-            self.log.removeHandler(self._log_handler)
             handler.root_topic = 'controller'
             handler.setLevel(self.log_level)
             self.log.addHandler(handler)
-            self._log_handler = handler
     
     @catch_config_error
     def initialize(self, argv=None):
         super(IPControllerApp, self).initialize(argv)
         self.forward_logging()
         self.load_secondary_config()
         self.init_hub()
         self.init_schedulers()
     
     def start(self):
         # Start the subprocesses:
         self.factory.start()
         # children must be started before signals are setup,
         # otherwise signal-handling will fire multiple times
         for child in self.children:
             child.start()
         self.init_signal()
 
         self.write_pid_file(overwrite=True)
 
         try:
             self.factory.loop.start()
         except KeyboardInterrupt:
             self.log.critical("Interrupted, Exiting...\n")
         finally:
             self.cleanup_connection_files()
             
 
 
 def launch_new_instance():
     """Create and run the IPython controller"""
     if sys.platform == 'win32':
         # make sure we don't get called from a multiprocessing subprocess
         # this can result in infinite Controllers being started on Windows
         # which doesn't have a proper fork, so multiprocessing is wonky
         
         # this only comes up when IPython has been installed using vanilla
         # setuptools, and *not* distribute.
         import multiprocessing
         p = multiprocessing.current_process()
         # the main process has name 'MainProcess'
         # subprocesses will have names like 'Process-1'
         if p.name != 'MainProcess':
             # we are a subprocess, don't start another Controller!
             return
     app = IPControllerApp.instance()
     app.initialize()
     app.start()
 
 
 if __name__ == '__main__':
     launch_new_instance()

IPython/parallel/apps/ipengineapp.py

@@ -1,336 +1,334 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 The IPython engine application
 
 Authors:
 
 * Brian Granger
 * MinRK
 
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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 json
 import os
 import sys
 import time
 
 import zmq
 from zmq.eventloop import ioloop
 
 from IPython.core.profiledir import ProfileDir
 from IPython.parallel.apps.baseapp import (
     BaseParallelApplication,
     base_aliases,
     base_flags,
     catch_config_error,
 )
 from IPython.zmq.log import EnginePUBHandler
 from IPython.zmq.ipkernel import Kernel
 from IPython.zmq.session import (
     Session, session_aliases, session_flags
 )
 
 from IPython.config.configurable import Configurable
 
 from IPython.parallel.engine.engine import EngineFactory
 from IPython.parallel.util import disambiguate_url
 
 from IPython.utils.importstring import import_item
 from IPython.utils.py3compat import cast_bytes
 from IPython.utils.traitlets import Bool, Unicode, Dict, List, Float
 
 
 #-----------------------------------------------------------------------------
 # Module level variables
 #-----------------------------------------------------------------------------
 
 #: The default config file name for this application
 default_config_file_name = u'ipengine_config.py'
 
 _description = """Start an IPython engine for parallel computing.
 
 IPython engines run in parallel and perform computations on behalf of a client
 and controller. A controller needs to be started before the engines. The
 engine can be configured using command line options or using a cluster
 directory. Cluster directories contain config, log and security files and are
 usually located in your ipython directory and named as "profile_name".
 See the `profile` and `profile-dir` options for details.
 """
 
 _examples = """
 ipengine --ip=192.168.0.1 --port=1000     # connect to hub at ip and port
 ipengine --log-to-file --log-level=DEBUG  # log to a file with DEBUG verbosity
 """
 
 #-----------------------------------------------------------------------------
 # MPI configuration
 #-----------------------------------------------------------------------------
 
 mpi4py_init = """from mpi4py import MPI as mpi
 mpi.size = mpi.COMM_WORLD.Get_size()
 mpi.rank = mpi.COMM_WORLD.Get_rank()
 """
 
 
 pytrilinos_init = """from PyTrilinos import Epetra
 class SimpleStruct:
 pass
 mpi = SimpleStruct()
 mpi.rank = 0
 mpi.size = 0
 """
 
 class MPI(Configurable):
     """Configurable for MPI initialization"""
     use = Unicode('', config=True,
         help='How to enable MPI (mpi4py, pytrilinos, or empty string to disable).'
         )
 
     def _use_changed(self, name, old, new):
         # load default init script if it's not set
         if not self.init_script:
             self.init_script = self.default_inits.get(new, '')
 
     init_script = Unicode('', config=True,
         help="Initialization code for MPI")
 
     default_inits = Dict({'mpi4py' : mpi4py_init, 'pytrilinos':pytrilinos_init},
         config=True)
 
 
 #-----------------------------------------------------------------------------
 # Main application
 #-----------------------------------------------------------------------------
 aliases = dict(
     file = 'IPEngineApp.url_file',
     c = 'IPEngineApp.startup_command',
     s = 'IPEngineApp.startup_script',
 
     url = 'EngineFactory.url',
     ssh = 'EngineFactory.sshserver',
     sshkey = 'EngineFactory.sshkey',
     ip = 'EngineFactory.ip',
     transport = 'EngineFactory.transport',
     port = 'EngineFactory.regport',
     location = 'EngineFactory.location',
 
     timeout = 'EngineFactory.timeout',
 
     mpi = 'MPI.use',
 
 )
 aliases.update(base_aliases)
 aliases.update(session_aliases)
 flags = {}
 flags.update(base_flags)
 flags.update(session_flags)
 
 class IPEngineApp(BaseParallelApplication):
 
     name = 'ipengine'
     description = _description
     examples = _examples
     config_file_name = Unicode(default_config_file_name)
     classes = List([ProfileDir, Session, EngineFactory, Kernel, MPI])
 
     startup_script = Unicode(u'', config=True,
         help='specify a script to be run at startup')
     startup_command = Unicode('', config=True,
             help='specify a command to be run at startup')
 
     url_file = Unicode(u'', config=True,
         help="""The full location of the file containing the connection information for
         the controller. If this is not given, the file must be in the
         security directory of the cluster directory.  This location is
         resolved using the `profile` or `profile_dir` options.""",
         )
     wait_for_url_file = Float(5, config=True,
         help="""The maximum number of seconds to wait for url_file to exist.
         This is useful for batch-systems and shared-filesystems where the
         controller and engine are started at the same time and it
         may take a moment for the controller to write the connector files.""")
 
     url_file_name = Unicode(u'ipcontroller-engine.json', config=True)
 
     def _cluster_id_changed(self, name, old, new):
         if new:
             base = 'ipcontroller-%s' % new
         else:
             base = 'ipcontroller'
         self.url_file_name = "%s-engine.json" % base
 
     log_url = Unicode('', config=True,
         help="""The URL for the iploggerapp instance, for forwarding
         logging to a central location.""")
 
     aliases = Dict(aliases)
     flags = Dict(flags)
     
     @property
     def kernel(self):
         """allow access to the Kernel object, so I look like IPKernelApp"""
         return self.engine.kernel
 
     def find_url_file(self):
         """Set the url file.
 
         Here we don't try to actually see if it exists for is valid as that
         is hadled by the connection logic.
         """
         config = self.config
         # Find the actual controller key file
         if not self.url_file:
             self.url_file = os.path.join(
                 self.profile_dir.security_dir,
                 self.url_file_name
             )
     
     def load_connector_file(self):
         """load config from a JSON connector file,
         at a *lower* priority than command-line/config files.
         """
         
         self.log.info("Loading url_file %r", self.url_file)
         config = self.config
         
         with open(self.url_file) as f:
             d = json.loads(f.read())
         
         if 'exec_key' in d:
             config.Session.key = cast_bytes(d['exec_key'])
         
         try:
             config.EngineFactory.location
         except AttributeError:
             config.EngineFactory.location = d['location']
         
         d['url'] = disambiguate_url(d['url'], config.EngineFactory.location)
         try:
             config.EngineFactory.url
         except AttributeError:
             config.EngineFactory.url = d['url']
         
         try:
             config.EngineFactory.sshserver
         except AttributeError:
             config.EngineFactory.sshserver = d['ssh']
         
     def init_engine(self):
         # This is the working dir by now.
         sys.path.insert(0, '')
         config = self.config
         # print config
         self.find_url_file()
         
         # was the url manually specified?
         keys = set(self.config.EngineFactory.keys())
         keys = keys.union(set(self.config.RegistrationFactory.keys()))
         
         if keys.intersection(set(['ip', 'url', 'port'])):
             # Connection info was specified, don't wait for the file
             url_specified = True
             self.wait_for_url_file = 0
         else:
             url_specified = False
 
         if self.wait_for_url_file and not os.path.exists(self.url_file):
             self.log.warn("url_file %r not found", self.url_file)
             self.log.warn("Waiting up to %.1f seconds for it to arrive.", self.wait_for_url_file)
             tic = time.time()
             while not os.path.exists(self.url_file) and (time.time()-tic < self.wait_for_url_file):
                 # wait for url_file to exist, or until time limit
                 time.sleep(0.1)
             
         if os.path.exists(self.url_file):
             self.load_connector_file()
         elif not url_specified:
             self.log.fatal("Fatal: url file never arrived: %s", self.url_file)
             self.exit(1)
         
         
         try:
             exec_lines = config.Kernel.exec_lines
         except AttributeError:
             config.Kernel.exec_lines = []
             exec_lines = config.Kernel.exec_lines
         
         if self.startup_script:
             enc = sys.getfilesystemencoding() or 'utf8'
             cmd="execfile(%r)" % self.startup_script.encode(enc)
             exec_lines.append(cmd)
         if self.startup_command:
             exec_lines.append(self.startup_command)
 
         # Create the underlying shell class and Engine
         # shell_class = import_item(self.master_config.Global.shell_class)
         # print self.config
         try:
             self.engine = EngineFactory(config=config, log=self.log)
         except:
             self.log.error("Couldn't start the Engine", exc_info=True)
             self.exit(1)
     
     def forward_logging(self):
         if self.log_url:
             self.log.info("Forwarding logging to %s", self.log_url)
             context = self.engine.context
             lsock = context.socket(zmq.PUB)
             lsock.connect(self.log_url)
-            self.log.removeHandler(self._log_handler)
             handler = EnginePUBHandler(self.engine, lsock)
             handler.setLevel(self.log_level)
             self.log.addHandler(handler)
-            self._log_handler = handler
     
     def init_mpi(self):
         global mpi
         self.mpi = MPI(config=self.config)
 
         mpi_import_statement = self.mpi.init_script
         if mpi_import_statement:
             try:
                 self.log.info("Initializing MPI:")
                 self.log.info(mpi_import_statement)
                 exec mpi_import_statement in globals()
             except:
                 mpi = None
         else:
             mpi = None
 
     @catch_config_error
     def initialize(self, argv=None):
         super(IPEngineApp, self).initialize(argv)
         self.init_mpi()
         self.init_engine()
         self.forward_logging()
     
     def start(self):
         self.engine.start()
         try:
             self.engine.loop.start()
         except KeyboardInterrupt:
             self.log.critical("Engine Interrupted, shutting down...\n")
 
 
 def launch_new_instance():
     """Create and run the IPython engine"""
     app = IPEngineApp.instance()
     app.initialize()
     app.start()
 
 
 if __name__ == '__main__':
     launch_new_instance()