|
|
"""Session object for building, serializing, sending, and receiving messages in
|
|
|
IPython. The Session object supports serialization, HMAC signatures, and
|
|
|
metadata on messages.
|
|
|
|
|
|
Also defined here are utilities for working with Sessions:
|
|
|
* A SessionFactory to be used as a base class for configurables that work with
|
|
|
Sessions.
|
|
|
* A Message object for convenience that allows attribute-access to the msg dict.
|
|
|
|
|
|
Authors:
|
|
|
|
|
|
* Min RK
|
|
|
* Brian Granger
|
|
|
* Fernando Perez
|
|
|
"""
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Copyright (C) 2010-2011 The IPython Development Team
|
|
|
#
|
|
|
# Distributed under the terms of the BSD License. The full license is in
|
|
|
# the file COPYING, distributed as part of this software.
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Imports
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
import hashlib
|
|
|
import hmac
|
|
|
import logging
|
|
|
import os
|
|
|
import pprint
|
|
|
import random
|
|
|
import uuid
|
|
|
from datetime import datetime
|
|
|
|
|
|
try:
|
|
|
import cPickle
|
|
|
pickle = cPickle
|
|
|
except:
|
|
|
cPickle = None
|
|
|
import pickle
|
|
|
|
|
|
try:
|
|
|
# We are using compare_digest to limit the surface of timing attacks
|
|
|
from hmac import compare_digest
|
|
|
except ImportError:
|
|
|
# Python < 2.7.7: When digests don't match no feedback is provided,
|
|
|
# limiting the surface of attack
|
|
|
def compare_digest(a,b): return a == b
|
|
|
|
|
|
import zmq
|
|
|
from zmq.utils import jsonapi
|
|
|
from zmq.eventloop.ioloop import IOLoop
|
|
|
from zmq.eventloop.zmqstream import ZMQStream
|
|
|
|
|
|
from IPython.config.configurable import Configurable, LoggingConfigurable
|
|
|
from IPython.utils import io
|
|
|
from IPython.utils.importstring import import_item
|
|
|
from IPython.utils.jsonutil import extract_dates, squash_dates, date_default
|
|
|
from IPython.utils.py3compat import (str_to_bytes, str_to_unicode, unicode_type,
|
|
|
iteritems)
|
|
|
from IPython.utils.traitlets import (CBytes, Unicode, Bool, Any, Instance, Set,
|
|
|
DottedObjectName, CUnicode, Dict, Integer,
|
|
|
TraitError,
|
|
|
)
|
|
|
from IPython.utils.pickleutil import PICKLE_PROTOCOL
|
|
|
from IPython.kernel.zmq.serialize import MAX_ITEMS, MAX_BYTES
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# utility functions
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
def squash_unicode(obj):
|
|
|
"""coerce unicode back to bytestrings."""
|
|
|
if isinstance(obj,dict):
|
|
|
for key in obj.keys():
|
|
|
obj[key] = squash_unicode(obj[key])
|
|
|
if isinstance(key, unicode_type):
|
|
|
obj[squash_unicode(key)] = obj.pop(key)
|
|
|
elif isinstance(obj, list):
|
|
|
for i,v in enumerate(obj):
|
|
|
obj[i] = squash_unicode(v)
|
|
|
elif isinstance(obj, unicode_type):
|
|
|
obj = obj.encode('utf8')
|
|
|
return obj
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# globals and defaults
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
# ISO8601-ify datetime objects
|
|
|
json_packer = lambda obj: jsonapi.dumps(obj, default=date_default)
|
|
|
json_unpacker = lambda s: jsonapi.loads(s)
|
|
|
|
|
|
pickle_packer = lambda o: pickle.dumps(squash_dates(o), PICKLE_PROTOCOL)
|
|
|
pickle_unpacker = pickle.loads
|
|
|
|
|
|
default_packer = json_packer
|
|
|
default_unpacker = json_unpacker
|
|
|
|
|
|
DELIM = b"<IDS|MSG>"
|
|
|
# singleton dummy tracker, which will always report as done
|
|
|
DONE = zmq.MessageTracker()
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Mixin tools for apps that use Sessions
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
session_aliases = dict(
|
|
|
ident = 'Session.session',
|
|
|
user = 'Session.username',
|
|
|
keyfile = 'Session.keyfile',
|
|
|
)
|
|
|
|
|
|
session_flags = {
|
|
|
'secure' : ({'Session' : { 'key' : str_to_bytes(str(uuid.uuid4())),
|
|
|
'keyfile' : '' }},
|
|
|
"""Use HMAC digests for authentication of messages.
|
|
|
Setting this flag will generate a new UUID to use as the HMAC key.
|
|
|
"""),
|
|
|
'no-secure' : ({'Session' : { 'key' : b'', 'keyfile' : '' }},
|
|
|
"""Don't authenticate messages."""),
|
|
|
}
|
|
|
|
|
|
def default_secure(cfg):
|
|
|
"""Set the default behavior for a config environment to be secure.
|
|
|
|
|
|
If Session.key/keyfile have not been set, set Session.key to
|
|
|
a new random UUID.
|
|
|
"""
|
|
|
|
|
|
if 'Session' in cfg:
|
|
|
if 'key' in cfg.Session or 'keyfile' in cfg.Session:
|
|
|
return
|
|
|
# key/keyfile not specified, generate new UUID:
|
|
|
cfg.Session.key = str_to_bytes(str(uuid.uuid4()))
|
|
|
|
|
|
|
|
|
#-----------------------------------------------------------------------------
|
|
|
# Classes
|
|
|
#-----------------------------------------------------------------------------
|
|
|
|
|
|
class SessionFactory(LoggingConfigurable):
|
|
|
"""The Base class for configurables that have a Session, Context, logger,
|
|
|
and IOLoop.
|
|
|
"""
|
|
|
|
|
|
logname = Unicode('')
|
|
|
def _logname_changed(self, name, old, new):
|
|
|
self.log = logging.getLogger(new)
|
|
|
|
|
|
# not configurable:
|
|
|
context = Instance('zmq.Context')
|
|
|
def _context_default(self):
|
|
|
return zmq.Context.instance()
|
|
|
|
|
|
session = Instance('IPython.kernel.zmq.session.Session')
|
|
|
|
|
|
loop = Instance('zmq.eventloop.ioloop.IOLoop', allow_none=False)
|
|
|
def _loop_default(self):
|
|
|
return IOLoop.instance()
|
|
|
|
|
|
def __init__(self, **kwargs):
|
|
|
super(SessionFactory, self).__init__(**kwargs)
|
|
|
|
|
|
if self.session is None:
|
|
|
# construct the session
|
|
|
self.session = Session(**kwargs)
|
|
|
|
|
|
|
|
|
class Message(object):
|
|
|
"""A simple message object that maps dict keys to attributes.
|
|
|
|
|
|
A Message can be created from a dict and a dict from a Message instance
|
|
|
simply by calling dict(msg_obj)."""
|
|
|
|
|
|
def __init__(self, msg_dict):
|
|
|
dct = self.__dict__
|
|
|
for k, v in iteritems(dict(msg_dict)):
|
|
|
if isinstance(v, dict):
|
|
|
v = Message(v)
|
|
|
dct[k] = v
|
|
|
|
|
|
# Having this iterator lets dict(msg_obj) work out of the box.
|
|
|
def __iter__(self):
|
|
|
return iter(iteritems(self.__dict__))
|
|
|
|
|
|
def __repr__(self):
|
|
|
return repr(self.__dict__)
|
|
|
|
|
|
def __str__(self):
|
|
|
return pprint.pformat(self.__dict__)
|
|
|
|
|
|
def __contains__(self, k):
|
|
|
return k in self.__dict__
|
|
|
|
|
|
def __getitem__(self, k):
|
|
|
return self.__dict__[k]
|
|
|
|
|
|
|
|
|
def msg_header(msg_id, msg_type, username, session):
|
|
|
date = datetime.now()
|
|
|
return locals()
|
|
|
|
|
|
def extract_header(msg_or_header):
|
|
|
"""Given a message or header, return the header."""
|
|
|
if not msg_or_header:
|
|
|
return {}
|
|
|
try:
|
|
|
# See if msg_or_header is the entire message.
|
|
|
h = msg_or_header['header']
|
|
|
except KeyError:
|
|
|
try:
|
|
|
# See if msg_or_header is just the header
|
|
|
h = msg_or_header['msg_id']
|
|
|
except KeyError:
|
|
|
raise
|
|
|
else:
|
|
|
h = msg_or_header
|
|
|
if not isinstance(h, dict):
|
|
|
h = dict(h)
|
|
|
return h
|
|
|
|
|
|
class Session(Configurable):
|
|
|
"""Object for handling serialization and sending of messages.
|
|
|
|
|
|
The Session object handles building messages and sending them
|
|
|
with ZMQ sockets or ZMQStream objects. Objects can communicate with each
|
|
|
other over the network via Session objects, and only need to work with the
|
|
|
dict-based IPython message spec. The Session will handle
|
|
|
serialization/deserialization, security, and metadata.
|
|
|
|
|
|
Sessions support configurable serialization via packer/unpacker traits,
|
|
|
and signing with HMAC digests via the key/keyfile traits.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
|
|
|
debug : bool
|
|
|
whether to trigger extra debugging statements
|
|
|
packer/unpacker : str : 'json', 'pickle' or import_string
|
|
|
importstrings for methods to serialize message parts. If just
|
|
|
'json' or 'pickle', predefined JSON and pickle packers will be used.
|
|
|
Otherwise, the entire importstring must be used.
|
|
|
|
|
|
The functions must accept at least valid JSON input, and output *bytes*.
|
|
|
|
|
|
For example, to use msgpack:
|
|
|
packer = 'msgpack.packb', unpacker='msgpack.unpackb'
|
|
|
pack/unpack : callables
|
|
|
You can also set the pack/unpack callables for serialization directly.
|
|
|
session : bytes
|
|
|
the ID of this Session object. The default is to generate a new UUID.
|
|
|
username : unicode
|
|
|
username added to message headers. The default is to ask the OS.
|
|
|
key : bytes
|
|
|
The key used to initialize an HMAC signature. If unset, messages
|
|
|
will not be signed or checked.
|
|
|
keyfile : filepath
|
|
|
The file containing a key. If this is set, `key` will be initialized
|
|
|
to the contents of the file.
|
|
|
|
|
|
"""
|
|
|
|
|
|
debug=Bool(False, config=True, help="""Debug output in the Session""")
|
|
|
|
|
|
packer = DottedObjectName('json',config=True,
|
|
|
help="""The name of the packer for serializing messages.
|
|
|
Should be one of 'json', 'pickle', or an import name
|
|
|
for a custom callable serializer.""")
|
|
|
def _packer_changed(self, name, old, new):
|
|
|
if new.lower() == 'json':
|
|
|
self.pack = json_packer
|
|
|
self.unpack = json_unpacker
|
|
|
self.unpacker = new
|
|
|
elif new.lower() == 'pickle':
|
|
|
self.pack = pickle_packer
|
|
|
self.unpack = pickle_unpacker
|
|
|
self.unpacker = new
|
|
|
else:
|
|
|
self.pack = import_item(str(new))
|
|
|
|
|
|
unpacker = DottedObjectName('json', config=True,
|
|
|
help="""The name of the unpacker for unserializing messages.
|
|
|
Only used with custom functions for `packer`.""")
|
|
|
def _unpacker_changed(self, name, old, new):
|
|
|
if new.lower() == 'json':
|
|
|
self.pack = json_packer
|
|
|
self.unpack = json_unpacker
|
|
|
self.packer = new
|
|
|
elif new.lower() == 'pickle':
|
|
|
self.pack = pickle_packer
|
|
|
self.unpack = pickle_unpacker
|
|
|
self.packer = new
|
|
|
else:
|
|
|
self.unpack = import_item(str(new))
|
|
|
|
|
|
session = CUnicode(u'', config=True,
|
|
|
help="""The UUID identifying this session.""")
|
|
|
def _session_default(self):
|
|
|
u = unicode_type(uuid.uuid4())
|
|
|
self.bsession = u.encode('ascii')
|
|
|
return u
|
|
|
|
|
|
def _session_changed(self, name, old, new):
|
|
|
self.bsession = self.session.encode('ascii')
|
|
|
|
|
|
# bsession is the session as bytes
|
|
|
bsession = CBytes(b'')
|
|
|
|
|
|
username = Unicode(str_to_unicode(os.environ.get('USER', 'username')),
|
|
|
help="""Username for the Session. Default is your system username.""",
|
|
|
config=True)
|
|
|
|
|
|
metadata = Dict({}, config=True,
|
|
|
help="""Metadata dictionary, which serves as the default top-level metadata dict for each message.""")
|
|
|
|
|
|
# message signature related traits:
|
|
|
|
|
|
key = CBytes(b'', config=True,
|
|
|
help="""execution key, for extra authentication.""")
|
|
|
def _key_changed(self, name, old, new):
|
|
|
if new:
|
|
|
self.auth = hmac.HMAC(new, digestmod=self.digest_mod)
|
|
|
else:
|
|
|
self.auth = None
|
|
|
|
|
|
signature_scheme = Unicode('hmac-sha256', config=True,
|
|
|
help="""The digest scheme used to construct the message signatures.
|
|
|
Must have the form 'hmac-HASH'.""")
|
|
|
def _signature_scheme_changed(self, name, old, new):
|
|
|
if not new.startswith('hmac-'):
|
|
|
raise TraitError("signature_scheme must start with 'hmac-', got %r" % new)
|
|
|
hash_name = new.split('-', 1)[1]
|
|
|
try:
|
|
|
self.digest_mod = getattr(hashlib, hash_name)
|
|
|
except AttributeError:
|
|
|
raise TraitError("hashlib has no such attribute: %s" % hash_name)
|
|
|
|
|
|
digest_mod = Any()
|
|
|
def _digest_mod_default(self):
|
|
|
return hashlib.sha256
|
|
|
|
|
|
auth = Instance(hmac.HMAC)
|
|
|
|
|
|
digest_history = Set()
|
|
|
digest_history_size = Integer(2**16, config=True,
|
|
|
help="""The maximum number of digests to remember.
|
|
|
|
|
|
The digest history will be culled when it exceeds this value.
|
|
|
"""
|
|
|
)
|
|
|
|
|
|
keyfile = Unicode('', config=True,
|
|
|
help="""path to file containing execution key.""")
|
|
|
def _keyfile_changed(self, name, old, new):
|
|
|
with open(new, 'rb') as f:
|
|
|
self.key = f.read().strip()
|
|
|
|
|
|
# for protecting against sends from forks
|
|
|
pid = Integer()
|
|
|
|
|
|
# serialization traits:
|
|
|
|
|
|
pack = Any(default_packer) # the actual packer function
|
|
|
def _pack_changed(self, name, old, new):
|
|
|
if not callable(new):
|
|
|
raise TypeError("packer must be callable, not %s"%type(new))
|
|
|
|
|
|
unpack = Any(default_unpacker) # the actual packer function
|
|
|
def _unpack_changed(self, name, old, new):
|
|
|
# unpacker is not checked - it is assumed to be
|
|
|
if not callable(new):
|
|
|
raise TypeError("unpacker must be callable, not %s"%type(new))
|
|
|
|
|
|
# thresholds:
|
|
|
copy_threshold = Integer(2**16, config=True,
|
|
|
help="Threshold (in bytes) beyond which a buffer should be sent without copying.")
|
|
|
buffer_threshold = Integer(MAX_BYTES, config=True,
|
|
|
help="Threshold (in bytes) beyond which an object's buffer should be extracted to avoid pickling.")
|
|
|
item_threshold = Integer(MAX_ITEMS, config=True,
|
|
|
help="""The maximum number of items for a container to be introspected for custom serialization.
|
|
|
Containers larger than this are pickled outright.
|
|
|
"""
|
|
|
)
|
|
|
|
|
|
|
|
|
def __init__(self, **kwargs):
|
|
|
"""create a Session object
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
|
|
|
debug : bool
|
|
|
whether to trigger extra debugging statements
|
|
|
packer/unpacker : str : 'json', 'pickle' or import_string
|
|
|
importstrings for methods to serialize message parts. If just
|
|
|
'json' or 'pickle', predefined JSON and pickle packers will be used.
|
|
|
Otherwise, the entire importstring must be used.
|
|
|
|
|
|
The functions must accept at least valid JSON input, and output
|
|
|
*bytes*.
|
|
|
|
|
|
For example, to use msgpack:
|
|
|
packer = 'msgpack.packb', unpacker='msgpack.unpackb'
|
|
|
pack/unpack : callables
|
|
|
You can also set the pack/unpack callables for serialization
|
|
|
directly.
|
|
|
session : unicode (must be ascii)
|
|
|
the ID of this Session object. The default is to generate a new
|
|
|
UUID.
|
|
|
bsession : bytes
|
|
|
The session as bytes
|
|
|
username : unicode
|
|
|
username added to message headers. The default is to ask the OS.
|
|
|
key : bytes
|
|
|
The key used to initialize an HMAC signature. If unset, messages
|
|
|
will not be signed or checked.
|
|
|
signature_scheme : str
|
|
|
The message digest scheme. Currently must be of the form 'hmac-HASH',
|
|
|
where 'HASH' is a hashing function available in Python's hashlib.
|
|
|
The default is 'hmac-sha256'.
|
|
|
This is ignored if 'key' is empty.
|
|
|
keyfile : filepath
|
|
|
The file containing a key. If this is set, `key` will be
|
|
|
initialized to the contents of the file.
|
|
|
"""
|
|
|
super(Session, self).__init__(**kwargs)
|
|
|
self._check_packers()
|
|
|
self.none = self.pack({})
|
|
|
# ensure self._session_default() if necessary, so bsession is defined:
|
|
|
self.session
|
|
|
self.pid = os.getpid()
|
|
|
|
|
|
@property
|
|
|
def msg_id(self):
|
|
|
"""always return new uuid"""
|
|
|
return str(uuid.uuid4())
|
|
|
|
|
|
def _check_packers(self):
|
|
|
"""check packers for datetime support."""
|
|
|
pack = self.pack
|
|
|
unpack = self.unpack
|
|
|
|
|
|
# check simple serialization
|
|
|
msg = dict(a=[1,'hi'])
|
|
|
try:
|
|
|
packed = pack(msg)
|
|
|
except Exception as e:
|
|
|
msg = "packer '{packer}' could not serialize a simple message: {e}{jsonmsg}"
|
|
|
if self.packer == 'json':
|
|
|
jsonmsg = "\nzmq.utils.jsonapi.jsonmod = %s" % jsonapi.jsonmod
|
|
|
else:
|
|
|
jsonmsg = ""
|
|
|
raise ValueError(
|
|
|
msg.format(packer=self.packer, e=e, jsonmsg=jsonmsg)
|
|
|
)
|
|
|
|
|
|
# ensure packed message is bytes
|
|
|
if not isinstance(packed, bytes):
|
|
|
raise ValueError("message packed to %r, but bytes are required"%type(packed))
|
|
|
|
|
|
# check that unpack is pack's inverse
|
|
|
try:
|
|
|
unpacked = unpack(packed)
|
|
|
assert unpacked == msg
|
|
|
except Exception as e:
|
|
|
msg = "unpacker '{unpacker}' could not handle output from packer '{packer}': {e}{jsonmsg}"
|
|
|
if self.packer == 'json':
|
|
|
jsonmsg = "\nzmq.utils.jsonapi.jsonmod = %s" % jsonapi.jsonmod
|
|
|
else:
|
|
|
jsonmsg = ""
|
|
|
raise ValueError(
|
|
|
msg.format(packer=self.packer, unpacker=self.unpacker, e=e, jsonmsg=jsonmsg)
|
|
|
)
|
|
|
|
|
|
# check datetime support
|
|
|
msg = dict(t=datetime.now())
|
|
|
try:
|
|
|
unpacked = unpack(pack(msg))
|
|
|
if isinstance(unpacked['t'], datetime):
|
|
|
raise ValueError("Shouldn't deserialize to datetime")
|
|
|
except Exception:
|
|
|
self.pack = lambda o: pack(squash_dates(o))
|
|
|
self.unpack = lambda s: unpack(s)
|
|
|
|
|
|
def msg_header(self, msg_type):
|
|
|
return msg_header(self.msg_id, msg_type, self.username, self.session)
|
|
|
|
|
|
def msg(self, msg_type, content=None, parent=None, header=None, metadata=None):
|
|
|
"""Return the nested message dict.
|
|
|
|
|
|
This format is different from what is sent over the wire. The
|
|
|
serialize/unserialize methods converts this nested message dict to the wire
|
|
|
format, which is a list of message parts.
|
|
|
"""
|
|
|
msg = {}
|
|
|
header = self.msg_header(msg_type) if header is None else header
|
|
|
msg['header'] = header
|
|
|
msg['msg_id'] = header['msg_id']
|
|
|
msg['msg_type'] = header['msg_type']
|
|
|
msg['parent_header'] = {} if parent is None else extract_header(parent)
|
|
|
msg['content'] = {} if content is None else content
|
|
|
msg['metadata'] = self.metadata.copy()
|
|
|
if metadata is not None:
|
|
|
msg['metadata'].update(metadata)
|
|
|
return msg
|
|
|
|
|
|
def sign(self, msg_list):
|
|
|
"""Sign a message with HMAC digest. If no auth, return b''.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
msg_list : list
|
|
|
The [p_header,p_parent,p_content] part of the message list.
|
|
|
"""
|
|
|
if self.auth is None:
|
|
|
return b''
|
|
|
h = self.auth.copy()
|
|
|
for m in msg_list:
|
|
|
h.update(m)
|
|
|
return str_to_bytes(h.hexdigest())
|
|
|
|
|
|
def serialize(self, msg, ident=None):
|
|
|
"""Serialize the message components to bytes.
|
|
|
|
|
|
This is roughly the inverse of unserialize. The serialize/unserialize
|
|
|
methods work with full message lists, whereas pack/unpack work with
|
|
|
the individual message parts in the message list.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
msg : dict or Message
|
|
|
The next message dict as returned by the self.msg method.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
msg_list : list
|
|
|
The list of bytes objects to be sent with the format::
|
|
|
|
|
|
[ident1, ident2, ..., DELIM, HMAC, p_header, p_parent,
|
|
|
p_metadata, p_content, buffer1, buffer2, ...]
|
|
|
|
|
|
In this list, the ``p_*`` entities are the packed or serialized
|
|
|
versions, so if JSON is used, these are utf8 encoded JSON strings.
|
|
|
"""
|
|
|
content = msg.get('content', {})
|
|
|
if content is None:
|
|
|
content = self.none
|
|
|
elif isinstance(content, dict):
|
|
|
content = self.pack(content)
|
|
|
elif isinstance(content, bytes):
|
|
|
# content is already packed, as in a relayed message
|
|
|
pass
|
|
|
elif isinstance(content, unicode_type):
|
|
|
# should be bytes, but JSON often spits out unicode
|
|
|
content = content.encode('utf8')
|
|
|
else:
|
|
|
raise TypeError("Content incorrect type: %s"%type(content))
|
|
|
|
|
|
real_message = [self.pack(msg['header']),
|
|
|
self.pack(msg['parent_header']),
|
|
|
self.pack(msg['metadata']),
|
|
|
content,
|
|
|
]
|
|
|
|
|
|
to_send = []
|
|
|
|
|
|
if isinstance(ident, list):
|
|
|
# accept list of idents
|
|
|
to_send.extend(ident)
|
|
|
elif ident is not None:
|
|
|
to_send.append(ident)
|
|
|
to_send.append(DELIM)
|
|
|
|
|
|
signature = self.sign(real_message)
|
|
|
to_send.append(signature)
|
|
|
|
|
|
to_send.extend(real_message)
|
|
|
|
|
|
return to_send
|
|
|
|
|
|
def send(self, stream, msg_or_type, content=None, parent=None, ident=None,
|
|
|
buffers=None, track=False, header=None, metadata=None):
|
|
|
"""Build and send a message via stream or socket.
|
|
|
|
|
|
The message format used by this function internally is as follows:
|
|
|
|
|
|
[ident1,ident2,...,DELIM,HMAC,p_header,p_parent,p_content,
|
|
|
buffer1,buffer2,...]
|
|
|
|
|
|
The serialize/unserialize methods convert the nested message dict into this
|
|
|
format.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
|
|
|
stream : zmq.Socket or ZMQStream
|
|
|
The socket-like object used to send the data.
|
|
|
msg_or_type : str or Message/dict
|
|
|
Normally, msg_or_type will be a msg_type unless a message is being
|
|
|
sent more than once. If a header is supplied, this can be set to
|
|
|
None and the msg_type will be pulled from the header.
|
|
|
|
|
|
content : dict or None
|
|
|
The content of the message (ignored if msg_or_type is a message).
|
|
|
header : dict or None
|
|
|
The header dict for the message (ignored if msg_to_type is a message).
|
|
|
parent : Message or dict or None
|
|
|
The parent or parent header describing the parent of this message
|
|
|
(ignored if msg_or_type is a message).
|
|
|
ident : bytes or list of bytes
|
|
|
The zmq.IDENTITY routing path.
|
|
|
metadata : dict or None
|
|
|
The metadata describing the message
|
|
|
buffers : list or None
|
|
|
The already-serialized buffers to be appended to the message.
|
|
|
track : bool
|
|
|
Whether to track. Only for use with Sockets, because ZMQStream
|
|
|
objects cannot track messages.
|
|
|
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
msg : dict
|
|
|
The constructed message.
|
|
|
"""
|
|
|
if not isinstance(stream, zmq.Socket):
|
|
|
# ZMQStreams and dummy sockets do not support tracking.
|
|
|
track = False
|
|
|
|
|
|
if isinstance(msg_or_type, (Message, dict)):
|
|
|
# We got a Message or message dict, not a msg_type so don't
|
|
|
# build a new Message.
|
|
|
msg = msg_or_type
|
|
|
else:
|
|
|
msg = self.msg(msg_or_type, content=content, parent=parent,
|
|
|
header=header, metadata=metadata)
|
|
|
if not os.getpid() == self.pid:
|
|
|
io.rprint("WARNING: attempted to send message from fork")
|
|
|
io.rprint(msg)
|
|
|
return
|
|
|
buffers = [] if buffers is None else buffers
|
|
|
to_send = self.serialize(msg, ident)
|
|
|
to_send.extend(buffers)
|
|
|
longest = max([ len(s) for s in to_send ])
|
|
|
copy = (longest < self.copy_threshold)
|
|
|
|
|
|
if buffers and track and not copy:
|
|
|
# only really track when we are doing zero-copy buffers
|
|
|
tracker = stream.send_multipart(to_send, copy=False, track=True)
|
|
|
else:
|
|
|
# use dummy tracker, which will be done immediately
|
|
|
tracker = DONE
|
|
|
stream.send_multipart(to_send, copy=copy)
|
|
|
|
|
|
if self.debug:
|
|
|
pprint.pprint(msg)
|
|
|
pprint.pprint(to_send)
|
|
|
pprint.pprint(buffers)
|
|
|
|
|
|
msg['tracker'] = tracker
|
|
|
|
|
|
return msg
|
|
|
|
|
|
def send_raw(self, stream, msg_list, flags=0, copy=True, ident=None):
|
|
|
"""Send a raw message via ident path.
|
|
|
|
|
|
This method is used to send a already serialized message.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
stream : ZMQStream or Socket
|
|
|
The ZMQ stream or socket to use for sending the message.
|
|
|
msg_list : list
|
|
|
The serialized list of messages to send. This only includes the
|
|
|
[p_header,p_parent,p_metadata,p_content,buffer1,buffer2,...] portion of
|
|
|
the message.
|
|
|
ident : ident or list
|
|
|
A single ident or a list of idents to use in sending.
|
|
|
"""
|
|
|
to_send = []
|
|
|
if isinstance(ident, bytes):
|
|
|
ident = [ident]
|
|
|
if ident is not None:
|
|
|
to_send.extend(ident)
|
|
|
|
|
|
to_send.append(DELIM)
|
|
|
to_send.append(self.sign(msg_list))
|
|
|
to_send.extend(msg_list)
|
|
|
stream.send_multipart(to_send, flags, copy=copy)
|
|
|
|
|
|
def recv(self, socket, mode=zmq.NOBLOCK, content=True, copy=True):
|
|
|
"""Receive and unpack a message.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
socket : ZMQStream or Socket
|
|
|
The socket or stream to use in receiving.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
[idents], msg
|
|
|
[idents] is a list of idents and msg is a nested message dict of
|
|
|
same format as self.msg returns.
|
|
|
"""
|
|
|
if isinstance(socket, ZMQStream):
|
|
|
socket = socket.socket
|
|
|
try:
|
|
|
msg_list = socket.recv_multipart(mode, copy=copy)
|
|
|
except zmq.ZMQError as e:
|
|
|
if e.errno == zmq.EAGAIN:
|
|
|
# We can convert EAGAIN to None as we know in this case
|
|
|
# recv_multipart won't return None.
|
|
|
return None,None
|
|
|
else:
|
|
|
raise
|
|
|
# split multipart message into identity list and message dict
|
|
|
# invalid large messages can cause very expensive string comparisons
|
|
|
idents, msg_list = self.feed_identities(msg_list, copy)
|
|
|
try:
|
|
|
return idents, self.unserialize(msg_list, content=content, copy=copy)
|
|
|
except Exception as e:
|
|
|
# TODO: handle it
|
|
|
raise e
|
|
|
|
|
|
def feed_identities(self, msg_list, copy=True):
|
|
|
"""Split the identities from the rest of the message.
|
|
|
|
|
|
Feed until DELIM is reached, then return the prefix as idents and
|
|
|
remainder as msg_list. This is easily broken by setting an IDENT to DELIM,
|
|
|
but that would be silly.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
msg_list : a list of Message or bytes objects
|
|
|
The message to be split.
|
|
|
copy : bool
|
|
|
flag determining whether the arguments are bytes or Messages
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
(idents, msg_list) : two lists
|
|
|
idents will always be a list of bytes, each of which is a ZMQ
|
|
|
identity. msg_list will be a list of bytes or zmq.Messages of the
|
|
|
form [HMAC,p_header,p_parent,p_content,buffer1,buffer2,...] and
|
|
|
should be unpackable/unserializable via self.unserialize at this
|
|
|
point.
|
|
|
"""
|
|
|
if copy:
|
|
|
idx = msg_list.index(DELIM)
|
|
|
return msg_list[:idx], msg_list[idx+1:]
|
|
|
else:
|
|
|
failed = True
|
|
|
for idx,m in enumerate(msg_list):
|
|
|
if m.bytes == DELIM:
|
|
|
failed = False
|
|
|
break
|
|
|
if failed:
|
|
|
raise ValueError("DELIM not in msg_list")
|
|
|
idents, msg_list = msg_list[:idx], msg_list[idx+1:]
|
|
|
return [m.bytes for m in idents], msg_list
|
|
|
|
|
|
def _add_digest(self, signature):
|
|
|
"""add a digest to history to protect against replay attacks"""
|
|
|
if self.digest_history_size == 0:
|
|
|
# no history, never add digests
|
|
|
return
|
|
|
|
|
|
self.digest_history.add(signature)
|
|
|
if len(self.digest_history) > self.digest_history_size:
|
|
|
# threshold reached, cull 10%
|
|
|
self._cull_digest_history()
|
|
|
|
|
|
def _cull_digest_history(self):
|
|
|
"""cull the digest history
|
|
|
|
|
|
Removes a randomly selected 10% of the digest history
|
|
|
"""
|
|
|
current = len(self.digest_history)
|
|
|
n_to_cull = max(int(current // 10), current - self.digest_history_size)
|
|
|
if n_to_cull >= current:
|
|
|
self.digest_history = set()
|
|
|
return
|
|
|
to_cull = random.sample(self.digest_history, n_to_cull)
|
|
|
self.digest_history.difference_update(to_cull)
|
|
|
|
|
|
def unserialize(self, msg_list, content=True, copy=True):
|
|
|
"""Unserialize a msg_list to a nested message dict.
|
|
|
|
|
|
This is roughly the inverse of serialize. The serialize/unserialize
|
|
|
methods work with full message lists, whereas pack/unpack work with
|
|
|
the individual message parts in the message list.
|
|
|
|
|
|
Parameters
|
|
|
----------
|
|
|
msg_list : list of bytes or Message objects
|
|
|
The list of message parts of the form [HMAC,p_header,p_parent,
|
|
|
p_metadata,p_content,buffer1,buffer2,...].
|
|
|
content : bool (True)
|
|
|
Whether to unpack the content dict (True), or leave it packed
|
|
|
(False).
|
|
|
copy : bool (True)
|
|
|
Whether to return the bytes (True), or the non-copying Message
|
|
|
object in each place (False).
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
msg : dict
|
|
|
The nested message dict with top-level keys [header, parent_header,
|
|
|
content, buffers].
|
|
|
"""
|
|
|
minlen = 5
|
|
|
message = {}
|
|
|
if not copy:
|
|
|
for i in range(minlen):
|
|
|
msg_list[i] = msg_list[i].bytes
|
|
|
if self.auth is not None:
|
|
|
signature = msg_list[0]
|
|
|
if not signature:
|
|
|
raise ValueError("Unsigned Message")
|
|
|
if signature in self.digest_history:
|
|
|
raise ValueError("Duplicate Signature: %r" % signature)
|
|
|
self._add_digest(signature)
|
|
|
check = self.sign(msg_list[1:5])
|
|
|
if not compare_digest(signature, check):
|
|
|
raise ValueError("Invalid Signature: %r" % signature)
|
|
|
if not len(msg_list) >= minlen:
|
|
|
raise TypeError("malformed message, must have at least %i elements"%minlen)
|
|
|
header = self.unpack(msg_list[1])
|
|
|
message['header'] = extract_dates(header)
|
|
|
message['msg_id'] = header['msg_id']
|
|
|
message['msg_type'] = header['msg_type']
|
|
|
message['parent_header'] = extract_dates(self.unpack(msg_list[2]))
|
|
|
message['metadata'] = self.unpack(msg_list[3])
|
|
|
if content:
|
|
|
message['content'] = self.unpack(msg_list[4])
|
|
|
else:
|
|
|
message['content'] = msg_list[4]
|
|
|
|
|
|
message['buffers'] = msg_list[5:]
|
|
|
return message
|
|
|
|
|
|
def test_msg2obj():
|
|
|
am = dict(x=1)
|
|
|
ao = Message(am)
|
|
|
assert ao.x == am['x']
|
|
|
|
|
|
am['y'] = dict(z=1)
|
|
|
ao = Message(am)
|
|
|
assert ao.y.z == am['y']['z']
|
|
|
|
|
|
k1, k2 = 'y', 'z'
|
|
|
assert ao[k1][k2] == am[k1][k2]
|
|
|
|
|
|
am2 = dict(ao)
|
|
|
assert am['x'] == am2['x']
|
|
|
assert am['y']['z'] == am2['y']['z']
|
|
|
|
|
|
|
