##// END OF EJS Templates
Handle kernel messages synchronously...
Handle kernel messages synchronously A problem can happen when two messages come in for different comms, where the second depends on the first (for example, the first might be a message setting the state of a widget, and the second triggering a view creation for the widget). Since comm message queues are independent of each other, the second message could be executed before the first message. This exposes a more fundamental assumption users are likely to have that messages from python are processed synchronously. Thanks to @dmadeka for reporting an error that led to discovering this issue.

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util.py
389 lines | 11.8 KiB | text/x-python | PythonLexer
"""Some generic utilities for dealing with classes, urls, and serialization."""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
import logging
import os
import re
import stat
import socket
import sys
import warnings
from signal import signal, SIGINT, SIGABRT, SIGTERM
try:
from signal import SIGKILL
except ImportError:
SIGKILL=None
from types import FunctionType
try:
import cPickle
pickle = cPickle
except:
cPickle = None
import pickle
import zmq
from zmq.log import handlers
from IPython.utils.log import get_logger
from IPython.external.decorator import decorator
from IPython.config.application import Application
from IPython.utils.localinterfaces import localhost, is_public_ip, public_ips
from IPython.utils.py3compat import string_types, iteritems, itervalues
from IPython.kernel.zmq.log import EnginePUBHandler
#-----------------------------------------------------------------------------
# Classes
#-----------------------------------------------------------------------------
class Namespace(dict):
"""Subclass of dict for attribute access to keys."""
def __getattr__(self, key):
"""getattr aliased to getitem"""
if key in self:
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 iteritems(self):
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, string_types):
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, string_types):
url = container
return validate_url(url)
elif isinstance(container, dict):
container = itervalues(container)
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 a connectable address
Explicit IP addresses are returned unmodified.
Parameters
----------
ip : IP address
An IP address, or the special values 0.0.0.0, or *
location: IP address, optional
A public IP of the target machine.
If location is an IP of the current machine,
localhost will be returned,
otherwise location will be returned.
"""
if ip in {'0.0.0.0', '*'}:
if not location:
# unspecified location, localhost is the only choice
ip = localhost()
elif is_public_ip(location):
# location is a public IP on this machine, use localhost
ip = localhost()
elif not public_ips():
# this machine's public IPs cannot be determined,
# assume `location` is not this machine
warnings.warn("IPython could not determine public IPs", RuntimeWarning)
ip = location
else:
# location is not this machine, do not use loopback
ip = 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().
"""
# build new FunctionType, so it can have the right globals
# interactive functions never have closures, that's kind of the point
if isinstance(f, FunctionType):
mainmod = __import__('__main__')
f = FunctionType(f.__code__, mainmod.__dict__,
f.__name__, f.__defaults__,
)
# associate with __main__ for uncanning
f.__module__ = '__main__'
return f
@interactive
def _push(**ns):
"""helper method for implementing `client.push` via `client.apply`"""
user_ns = globals()
tmp = '_IP_PUSH_TMP_'
while tmp in user_ns:
tmp = tmp + '_'
try:
for name, value in ns.items():
user_ns[tmp] = value
exec("%s = %s" % (name, tmp), user_ns)
finally:
user_ns.pop(tmp, None)
@interactive
def _pull(keys):
"""helper method for implementing `client.pull` via `client.apply`"""
if isinstance(keys, (list,tuple, set)):
return [eval(key, globals()) for key in keys]
else:
return eval(keys, globals())
@interactive
def _execute(code):
"""helper method for implementing `client.execute` via `client.apply`"""
exec(code, 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 range(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 = get_logger()
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
def set_hwm(sock, hwm=0):
"""set zmq High Water Mark on a socket
in a way that always works for various pyzmq / libzmq versions.
"""
import zmq
for key in ('HWM', 'SNDHWM', 'RCVHWM'):
opt = getattr(zmq, key, None)
if opt is None:
continue
try:
sock.setsockopt(opt, hwm)
except zmq.ZMQError:
pass