"""
Classes for network communication.
There are two general types of network objects -
* :class:`.Station` and its children are independent processes that should only be instantiated once
per piece of hardware. They are used to distribute messages between :class:`.Net_Node` s,
forward messages up the networking tree, and responding to messages that don't need any input from
the :class:`~.pilot.Pilot` or :class:`~.terminal.Terminal`.
* :class:`.Net_Node` is a pop-in networking class that can be given to any other object that
wants to send or receive messages.
"""
import json
import logging
import threading
import zmq
import sys
import datetime
import time
import os
import multiprocessing
import base64
import socket
from copy import copy
from tornado.ioloop import IOLoop
from zmq.eventloop.zmqstream import ZMQStream
from itertools import count
if sys.version_info >= (3,0):
import queue
else:
import Queue as queue
from autopilot import prefs
# TODO: Periodically ping pis to check that they are still responsive
class Station(multiprocessing.Process):
"""
Independent networking class used for messaging between computers.
These objects send and handle :class:`.networking.Message` s by using a
dictionary of :attr:`~.networking.Station.listens`, or methods
that are called to respond to different types of messages.
Each sent message is given an ID, and a thread is spawned to periodically
resend it (up until some time-to-live, typically 5 times) until confirmation
is received.
By default, the only listen these objects have is :meth:`.l_confirm`,
which responds to message confirmations. Accordingly, `listens` should be added
by using :meth:`dict.update` rather than reassigning the attribute.
Station objects can be made with or without a :attr:`~.networking.Station.pusher`,
a :class:`zmq.DEALER` socket that connects to the :class:`zmq.ROUTER`
socket of an upstream Station object.
This class should not be instantiated on its own, but should instead
be subclassed in order to provide methods used by :meth:`~.Station.handle_listen`.
Attributes:
ctx (:class:`zmq.Context`): zeromq context
loop (:class:`tornado.ioloop.IOLoop`): a tornado ioloop
pusher (:class:`zmq.Socket`): pusher socket - a dealer socket that connects to other routers
push_ip (str): If we have a dealer, IP to push messages to
push_port (str): If we have a dealer, port to push messages to
push_id (str): :attr:`~zmq.Socket.identity` of the Router we push to
listener (:class:`zmq.Socket`): The main router socket to send/recv messages
listen_port (str): Port our router listens on
logger (:class:`logging.Logger`): Used to log messages and network events.
log_handler (:class:`logging.FileHandler`): Handler for logging
log_formatter (:class:`logging.Formatter`): Formats log entries as::
"%(asctime)s %(levelname)s : %(message)s"
id (str): What are we known as? What do we set our :attr:`~zmq.Socket.identity` as?
ip (str): Device IP
listens (dict): Dictionary of functions to call for different types of messages. keys match the :attr:`.Message.key`.
senders (dict): Identities of other sockets (keys, ie. directly connected) and their state (values) if they keep one
outbox (dict): Messages that have been sent but have not been confirmed
timers (dict): dict of :class:`threading.Timer` s that will check in on outbox messages
msg_counter (:class:`itertools.count`): counter to index our sent messages
file_block (:class:`threading.Event`): Event to signal when a file is being received.
"""
ctx = None # Context
loop = None # IOLoop
push_ip = None # IP to push to
push_port = None # Publisher Port
push_id = "" # Identity of the Router we push to
listen_port = None # Listener Port
pusher = None # pusher socket - a dealer socket that connects to other routers
listener = None # Listener socket - a router socket to send/recv messages
logger = None # Logger....
do_logging = multiprocessing.Event()
do_logging.set()
log_handler = None
log_formatter = None
id = None # What are we known as?
ip = None # whatismy
listens = {} # Dictionary of functions to call for different types of messages
senders = {} # who has sent us stuff (ie. directly connected) and their state if they keep one
push_outbox = {} # Messages that are out with unconfirmed delivery
send_outbox = {} # Messages that are out with unconfirmed delivery
timers = {} # dict of timer threads that will check in on outbox messages
child = False
routes = {} # dict of 'to' addressee and the route that should be taken to reach them
repeat_interval = 5.0 # seconds to wait before retrying messages
def __init__(self):
super(Station, self).__init__()
# Prefs should be passed by the terminal, if not, try to load from default locatio
self.ip = self.get_ip()
# Setup logging
self.init_logging()
self.file_block = threading.Event() # to wait for file transfer
# number messages as we send them
self.msg_counter = count()
# we have a few builtin listens
self.listens = {
'CONFIRM': self.l_confirm
}
# even tthat signals when we are closing
self.closing = threading.Event()
self.closing.clear()
# start thread that periodically resends messages
self.repeat_thread = threading.Thread(target=self.repeat)
self.repeat_thread.setDaemon(True)
self.repeat_thread.start()
def __del__(self):
self.closing.set()
# Stopping the loop should kill the process, as it's what's holding us in run()
self.loop.stop()
def run(self):
"""
A :class:`zmq.Context` and :class:`tornado.IOLoop` are spawned,
the listener and optionally the pusher are instantiated and
connected to :meth:`~.Station.handle_listen` using
:meth:`~zmq.eventloop.zmqstream.ZMQStream.on_recv` .
The process is kept open by the :class:`tornado.IOLoop` .
"""
# init zmq objects
self.context = zmq.Context()
self.loop = IOLoop()
# Our networking topology is treelike:
# each Station object binds one Router to
# send and receive messages from its descendants
# each Station object may have one Dealer that
# connects it with its antecedents.
self.listener = self.context.socket(zmq.ROUTER)
self.listener.identity = self.id.encode('utf-8')
self.listener.bind('tcp://*:{}'.format(self.listen_port))
self.listener = ZMQStream(self.listener, self.loop)
self.listener.on_recv(self.handle_listen)
if self.pusher is True:
self.pusher = self.context.socket(zmq.DEALER)
self.pusher.identity = self.id.encode('utf-8')
self.pusher.connect('tcp://{}:{}'.format(self.push_ip, self.push_port))
self.pusher = ZMQStream(self.pusher, self.loop)
self.pusher.on_recv(self.handle_listen)
# TODO: Make sure handle_listen knows how to handle ID-less messages
self.logger.info('Starting IOLoop')
self.loop.start()
def prepare_message(self, to, key, value, repeat=True, flags=None):
"""
If a message originates with us, a :class:`.Message` class
is instantiated, given an ID and the rest of its attributes.
Args:
to (str): The identity of the socket this message is to
key (str): The type of message - used to select which method the receiver
uses to process this message.
value: Any information this message should contain. Can be any type, but
must be JSON serializable.
"""
msg = Message()
msg.sender = self.id
msg.to = to
msg.key = key
msg.value = value
msg_num = self.msg_counter.next()
msg.id = "{}_{}".format(self.id, msg_num)
if not repeat:
msg.flags['NOREPEAT'] = True
if flags:
for k, v in flags.items():
msg.flags[k] = v
return msg
def send(self, to=None, key=None, value=None, msg=None, repeat=True, flags=None):
"""
Send a message via our :attr:`~.Station.listener` , ROUTER socket.
Either an already created :class:`.Message` should be passed as `msg`,
or at least `to` and `key` must be provided for a new message created
by :meth:`~.Station.prepare_message` .
A :class:`threading.Timer` is created to resend the message using
:meth:`~.Station.repeat` unless `repeat` is False.
Args:
to (str): The identity of the socket this message is to
key (str): The type of message - used to select which method the receiver
uses to process this message.
value: Any information this message should contain. Can be any type, but
must be JSON serializable.
msg (`.Message`): An already created message.
repeat (bool): Should this message be resent if confirmation is not received?
"""
if not msg and not all([to, key]):
self.logger.exception('Need either a message or \'to\' and \'key\' fields.\
Got\nto: {}\nkey: {}\nvalue: {}\nmsg: {}'.format(to, key, value, msg))
return
if not msg:
# we're sending this ourselves, new message.
msg = self.prepare_message(to, key, value, repeat, flags)
if 'NOREPEAT' in msg.flags.keys():
repeat = False
# if we didn't send it, we shouldn't double-confirm it.
if msg.sender not in [self.name, '_'+self.name]:
repeat = False
# Make sure our message has everything
if not msg.validate():
self.logger.error('Message Invalid:\n{}'.format(str(msg)))
# encode message
msg_enc = msg.serialize()
if not msg_enc:
self.logger.error('Message could not be encoded:\n{}'.format(str(msg)))
return
if isinstance(msg.to, list):
self.listener.send_multipart([bytes(msg.to[0]), msg_enc])
else:
self.listener.send_multipart([bytes(msg.to), msg_enc])
# messages can have a flag that says not to log
log_this = True
if 'NOLOG' in msg.flags.keys():
log_this = False
if (msg.key != "CONFIRM") and self.do_logging.is_set() and log_this:
self.logger.info('MESSAGE SENT - {}'.format(str(msg)))
if repeat and not msg.key == "CONFIRM":
# add to outbox and spawn timer to resend
self.send_outbox[msg.id] = (time.time(), msg)
# self.timers[msg.id] = threading.Timer(5.0, self.repeat, args=(msg.id,'send'))
# self.timers[msg.id].start()
#self.outbox.put((msg.id))
def push(self, to=None, key = None, value = None, msg=None, repeat=True, flags=None):
"""
Send a message via our :attr:`~.Station.pusher` , DEALER socket.
Unlike :meth:`~.Station.send` , `to` is not required. Every message
is always sent to :attr:`~.Station.push_id` . `to` can be included
to send a message further up the network tree to a networking object
we're not directly connected to.
Either an already created :class:`.Message` should be passed as `msg`,
or at least `key` must be provided for a new message created
by :meth:`~.Station.prepare_message` .
A :class:`threading.Timer` is created to resend the message using
:meth:`~.Station.repeat` unless `repeat` is False.
Args:
to (str): The identity of the socket this message is to. If not included,
sent to :meth:`~.Station.push_id` .
key (str): The type of message - used to select which method the receiver
uses to process this message.
value: Any information this message should contain. Can be any type, but
must be JSON serializable.
msg (`.Message`): An already created message.
repeat (bool): Should this message be resent if confirmation is not received?
"""
# send message via the dealer
# even though we only have one connection over our dealer,
# we still include 'to' in case we are sending further upstream
# but can push without 'to', just fill in with upstream id
if not msg and not key:
self.logger.exception('Need either a message or a \'key\' field.\
Got\nto: {}\nkey: {}\nvalue: {}\nmsg: {}'.format(to, key, value, msg))
if not msg:
if to is None:
to = self.push_id
msg = self.prepare_message(to, key, value, repeat, flags)
if 'NOREPEAT' in msg.flags.keys():
repeat = False
log_this = True
if 'NOLOG' in msg.flags.keys():
log_this = False
# Make sure our message has everything
if not msg.validate():
self.logger.error('Message Invalid:\n{}'.format(str(msg)))
# encode message
msg_enc = msg.serialize()
if not msg_enc:
self.logger.error('Message could not be encoded:\n{}'.format(str(msg)))
return
# Even if the message is not to our upstream node, we still send it
# upstream because presumably our target is upstream.
self.pusher.send_multipart([bytes(self.push_id), msg_enc])
if not (msg.key == "CONFIRM") and self.do_logging.is_set() and log_this:
self.logger.info('MESSAGE PUSHED - {}'.format(str(msg)))
if repeat and not msg.key == 'CONFIRM':
# add to outbox and spawn timer to resend
self.push_outbox[msg.id] = (time.time(), msg)
#self.timers[msg.id] = threading.Timer(5.0, self.repeat, args=(msg.id, 'push'))
#self.timers[msg.id].start()
def repeat(self):
"""
Periodically (according to :attr:`~.repeat_interval`) resend messages that haven't been confirmed
TTL is decremented, and messages are resent until their TTL is 0.
"""
while not self.closing.is_set():
# make local copies
push_outbox = copy(self.push_outbox)
send_outbox = copy(self.send_outbox)
# try to send any outstanding messages and delete if too old
if len(push_outbox)>0:
for id in push_outbox.keys():
if push_outbox[id][1].ttl <= 0:
self.logger.warning('PUBLISH FAILED {} - {}'.format(id, str(push_outbox[id][1])))
try:
del self.push_outbox[id]
except KeyError:
# fine, already deleted
pass
else:
# if we didn't just put this message in our outbox
if (time.time() - push_outbox[id][0]) > self.repeat_interval:
if self.do_logging.is_set():
self.logger.info('REPUBLISH {} - {}'.format(id, str(push_outbox[id][1])))
self.pusher.send_multipart([bytes(self.push_id), push_outbox[id][1].serialize()])
self.push_outbox[id][1].ttl -= 1
if len(send_outbox)>0:
for id in send_outbox.keys():
if send_outbox[id][1].ttl <= 0:
self.logger.warning('PUBLISH FAILED {} - {}'.format(id, str(send_outbox[id][1])))
try:
del self.send_outbox[id]
except KeyError:
# fine, already deleted
pass
else:
# if we didn't just put this message in our outbox
if (time.time() - send_outbox[id][0]) > self.repeat_interval:
if self.do_logging.is_set():
self.logger.info('REPUBLISH {} - {}'.format(id, str(send_outbox[id][1])))
self.listener.send_multipart([bytes(send_outbox[id][1].to), send_outbox[id][1].serialize()])
self.send_outbox[id][1].ttl -= 1
# wait to do it again
time.sleep(self.repeat_interval)
def l_confirm(self, msg):
"""
Confirm that a message was received.
Args:
msg (:class:`.Message`): A confirmation message - note that this message has its own unique ID, so the value of this message contains the ID of the message that is being confirmed
"""
# confirmation that a published message was received
# value should be the message id
# delete message from outbox if we still have it
try:
if msg.value in self.send_outbox.keys():
del self.send_outbox[msg.id]
elif msg.value in self.push_outbox.keys():
del self.push_outbox[msg.id]
except KeyError:
# fine, already deleted
pass
#self.logger.info('CONFIRMED MESSAGE {}'.format(msg.value))
def handle_listen(self, msg):
"""
Upon receiving a message, call the appropriate listen method
in a new thread.
If the message is :attr:`~.Message.to` us, send confirmation.
If the message is not :attr:`~.Message.to` us, attempt to forward it.
Args:
msg (str): JSON :meth:`.Message.serialize` d message.
"""
# TODO: This check is v. fragile, pyzmq has a way of sending the stream along with the message
#####################33
# Parse the message
if len(msg)==1:
# from our dealer
send_type = 'dealer'
msg = json.loads(msg[0])
msg = Message(**msg)
elif len(msg)>=2:
# from the router
send_type = 'router'
sender = msg[-3]
# if this message was a multihop message, store the route
if len(msg)>3:
self.routes[sender] = msg[0:-2]
# # if this is a new sender, add them to the list
if sender not in self.senders.keys():
self.senders[sender] = ""
self.senders['_' + sender] = ''
# connection pings are blank frames,
# respond to let them know we're alive
if msg[-1] == b'':
self.listener.send_multipart(msg)
return
msg = json.loads(msg[-1])
msg = Message(**msg)
# if this is a new sender, add them to the list
if msg['sender'] not in self.senders.keys():
self.senders[msg['sender']] = ""
self.senders['_' + msg['sender']] = ''
else:
self.logger.error('Dont know what this message is:{}'.format(msg))
return
# Check if our listen was sent properly
if not msg.validate():
self.logger.error('Message failed to validate:\n{}'.format(str(msg)))
return
###################################
# Handle the message
# if this message has a multihop 'to' field, forward it along
# some messages have a flag not to log them
log_this = True
if 'NOLOG' in msg.flags.keys():
log_this = False
if isinstance(msg.to, list):
if len(msg.to) == 1:
msg.to = msg.to[0]
if isinstance(msg.to, list):
# pop ourselves off the list
_ = msg.to.pop(0)
# if the next recipient in the list is our push-parent, push it
if msg.to[0] == self.push_id:
self.push(msg=msg)
else:
self.send(msg=msg)
# if this message is to us, just handle it and return
elif msg.to in [self.id, "_{}".format(self.id)]:
if (msg.key != "CONFIRM") and self.do_logging.is_set() and log_this:
self.logger.info('RECEIVED: {}'.format(str(msg)))
# Log and spawn thread to respond to listen
try:
listen_funk = self.listens[msg.key]
listen_thread = threading.Thread(target=listen_funk, args=(msg,))
listen_thread.start()
except KeyError:
self.logger.exception('ERROR: No function could be found for msg id {} with key: {}'.format(msg.id, msg.key))
# send a return message that confirms even if we except
# don't confirm confirmations
if (msg.key != "CONFIRM") and ('NOREPEAT' not in msg.flags.keys()):
if send_type == 'router':
self.send(sender, 'CONFIRM', msg.id)
elif send_type == 'dealer':
self.push(msg.sender, 'CONFIRM', msg.id)
return
# otherwise, if it's to someone we know about, send it there
elif self.child and (msg.to == 'T'):
# FIXME UGLY HACK
self.push(msg=msg)
elif msg.to in self.senders.keys():
self.send(msg=msg)
# otherwise, if we have a pusher, send it there
# it's either for them or some other upstream node we don't know about
elif self.pusher:
self.push(msg=msg)
else:
if self.do_logging.is_set():
self.logger.warning('Message to unconfirmed recipient, attempting to send: {}'.format(str(msg)))
self.send(msg=msg)
# finally, if there's something we're supposed to do, do it
# even if the message is not to us,
# sometimes we do work en passant to reduce effort doubling
# FIXME Seems like a really bad idea.
if msg.key in self.listens.keys():
listen_funk = self.listens[msg.key]
listen_thread = threading.Thread(target=listen_funk, args=(msg,))
listen_thread.start()
# since we return if it's to us before, confirm is repeated down here.
# FIXME: Inelegant
if (msg.key != "CONFIRM") and ('NOREPEAT' not in msg.flags.keys()):
if send_type == 'router':
self.send(sender, 'CONFIRM', msg.id)
elif send_type == 'dealer':
self.push(msg.sender, 'CONFIRM', msg.id)
def init_logging(self):
"""
Initialize logging to a timestamped file in `prefs.LOGDIR` .
"""
# Setup logging
timestr = datetime.datetime.now().strftime('%y%m%d_%H%M%S')
log_file = os.path.join(prefs.LOGDIR, 'Networking_Log_{}.log'.format(timestr))
self.logger = logging.getLogger('networking')
self.log_handler = logging.FileHandler(log_file)
self.log_formatter = logging.Formatter("%(asctime)s %(levelname)s : %(message)s")
self.log_handler.setFormatter(self.log_formatter)
self.logger.addHandler(self.log_handler)
self.logger.setLevel(logging.INFO)
self.logger.info('Station Logging Initiated')
def get_ip(self):
"""
Find our IP address
returns (str): our IPv4 address.
"""
# shamelessly stolen from https://www.w3resource.com/python-exercises/python-basic-exercise-55.php
# variables are badly named because this is just a rough unwrapping of what was a monstrous one-liner
# (and i don't really understand how it works)
# get ips that aren't the loopback
unwrap00 = [ip for ip in socket.gethostbyname_ex(socket.gethostname())[2] if not ip.startswith("127.")][:1]
# ??? truly dk
unwrap01 = [[(s.connect(('8.8.8.8', 53)), s.getsockname()[0], s.close()) for s in
[socket.socket(socket.AF_INET, socket.SOCK_DGRAM)]][0][1]]
unwrap2 = [l for l in (unwrap00, unwrap01) if l][0][0]
return unwrap2
def set_logging(self, do_logging):
if do_logging:
self.do_logging.set()
else:
self.do_logging.clear()
class Terminal_Station(Station):
"""
:class:`~.networking.Station` object used by :class:`~.Terminal`
objects.
Spawned without a :attr:`~.Station.pusher`.
**Listens**
+-------------+-------------------------------------------+-----------------------------------------------+
| Key | Method | Description |
+=============+===========================================+===============================================+
| 'PING' | :meth:`~.Terminal_Station.l_ping` | We are asked to confirm that we are alive |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'INIT' | :meth:`~.Terminal_Station.l_init` | Ask all pilots to confirm that they are alive |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'CHANGE' | :meth:`~.Terminal_Station.l_change` | Change a parameter on the Pi |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'STOPALL' | :meth:`~.Terminal_Station.l_stopall` | Stop all pilots and plots |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'KILL' | :meth:`~.Terminal_Station.l_kill` | Terminal wants us to die :( |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'DATA' | :meth:`~.Terminal_Station.l_data` | Stash incoming data from a Pilot |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'STATE' | :meth:`~.Terminal_Station.l_state` | A Pilot has changed state |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'HANDSHAKE' | :meth:`~.Terminal_Station.l_handshake` | A Pi is telling us it's alive and its IP |
+-------------+-------------------------------------------+-----------------------------------------------+
| 'FILE' | :meth:`~.Terminal_Station.l_file` | The pi needs some file from us |
+-------------+-------------------------------------------+-----------------------------------------------+
"""
def __init__(self, pilots):
"""
Args:
pilots (dict): The :attr:`.Terminal.pilots` dictionary.
"""
super(Terminal_Station, self).__init__()
# by default terminal doesn't have a pusher, everything connects to it
self.pusher = False
# Store some prefs values
self.listen_port = prefs.MSGPORT
self.id = b'T'
# Message dictionary - What method to call for each type of message received by the terminal class
self.listens.update({
'PING': self.l_ping, # We are asked to confirm that we are alive
'INIT': self.l_init, # We should ask all the pilots to confirm that they are alive
'CHANGE': self.l_change, # Change a parameter on the Pi
'STOPALL': self.l_stopall, # Stop all pilots and plots
'KILL': self.l_kill, # Terminal wants us to die :(
'DATA': self.l_data, # Stash incoming data from an autopilot
'STATE': self.l_state, # The Pi is confirming/notifying us that it has changed state
'HANDSHAKE': self.l_handshake, # initial connection with some initial info
'FILE': self.l_file, # The pi needs some file from us
})
# dictionary that keeps track of our pilots
self.pilots = pilots
##########################
# Message Handling Methods
def l_ping(self, msg):
"""
We are asked to confirm that we are alive
Respond with a blank 'STATE' message.
Args:
msg (:class:`.Message`):
"""
# we are being asked if we're alive
# respond with blank message since the terminal isn't really stateful
self.send(msg.sender, 'STATE', flags={'NOLOG':True})
def l_init(self, msg):
"""
Ask all pilots to confirm that they are alive
Sends a "PING" to everyone in the pilots dictionary.
Args:
msg (:class:`.Message`):
"""
# Ping all pis that we are expecting given our pilot db
# Responses will be handled with l_state so not much needed here
for p in self.pilots.keys():
self.send(p, 'PING', flags={'NOLOG':True})
def l_change(self, msg):
"""
Change a parameter on the Pi
Warning:
Not Implemented
Args:
msg (:class:`.Message`):
"""
# TODO: Should also handle param changes to GUI objects like ntrials, etc.
pass
def l_stopall(self, msg):
"""
Stop all pilots and plots
Args:
msg (:class:`.Message`):
"""
# let all the pilots and plot objects know that they should stop
for p in self.pilots.keys():
self.send(p, 'STOP')
self.send("P_{}".format(p), 'STOP')
def l_kill(self, msg):
"""
Terminal wants us to die :(
Stop the :attr:`.Station.loop`
Args:
msg (:class:`.Message`):
"""
self.logger.info('Received kill request')
self.closing.set()
# Stopping the loop should kill the process, as it's what's holding us in run()
self.loop.stop()
def l_data(self, msg):
"""
Stash incoming data from a Pilot
Just forward this along to the internal terminal object ('_T')
and a copy to the relevant plot.
Args:
msg (:class:`.Message`):
"""
# Send through to terminal
self.send('_T', 'DATA', msg.value)
# Send to plot widget, which should be listening to "P_{pilot_name}"
self.send('P_{}'.format(msg.value['pilot']), 'DATA', msg.value)
def l_state(self, msg):
"""
A Pilot has changed state.
Stash in 'state' field of pilot dict and send along to _T
Args:
msg (:class:`.Message`):
"""
if msg.sender in self.pilots.keys():
#if 'state' in self.pilots[msg.sender].keys():
# if msg.value == self.pilots[msg.sender]['state']:
# # if we've already gotten this one, don't send to terminal
# return
self.pilots[msg.sender]['state'] = msg.value
# Tell the terminal so it can update the pilot_db file
state = {'state':msg.value, 'pilot':msg.sender}
self.send('_T', 'STATE', state)
# Tell the plot
self.send("P_{}".format(msg.sender), 'STATE', msg.value)
self.senders[msg.sender] = msg.value
def l_handshake(self, msg):
"""
A Pi is telling us it's alive and its IP.
Send along to _T
Args:
msg (:class:`.Message`):
"""
# only rly useful for our terminal object
self.send('_T', 'HANDSHAKE', value=msg.value)
def l_file(self, msg):
"""
A Pilot needs some file from us.
Send it back after :meth:`base64.b64encode` ing it.
TODO:
Split large files into multiple messages...
Args:
msg (:class:`.Message`): The value field of the message should contain some
relative path to a file contained within `prefs.SOUNDDIR` . eg.
`'/songs/sadone.wav'` would return `'os.path.join(prefs.SOUNDDIR/songs.sadone.wav'`
"""
# The <target> pi has requested some file <value> from us, let's send it back
# This assumes the file is small, if this starts crashing we'll have to split the message...
full_path = os.path.join(prefs.SOUNDDIR, msg.value)
with open(full_path, 'rb') as open_file:
# encode in base64 so json doesn't complain
file_contents = base64.b64encode(open_file.read())
file_message = {'path':msg.value, 'file':file_contents}
self.send(msg.sender, 'FILE', file_message)
class Pilot_Station(Station):
"""
:class:`~.networking.Station` object used by :class:`~.Pilot`
objects.
Spawned with a :attr:`~.Station.pusher` connected back to the
:class:`~.Terminal` .
**Listens**
+-------------+-------------------------------------+-----------------------------------------------+
| Key | Method | Description |
+=============+=====================================+===============================================+
| 'STATE' | :meth:`~.Pilot_Station.l_state` | Pilot has changed state |
| 'COHERE' | :meth:`~.Pilot_Station.l_cohere` | Make sure our data and the Terminal's match. |
| 'PING' | :meth:`~.Pilot_Station.l_ping` | The Terminal wants to know if we're listening |
| 'START' | :meth:`~.Pilot_Station.l_start` | We are being sent a task to start |
| 'STOP' | :meth:`~.Pilot_Station.l_stop` | We are being told to stop the current task |
| 'PARAM' | :meth:`~.Pilot_Station.l_change` | The Terminal is changing some task parameter |
| 'FILE' | :meth:`~.Pilot_Station.l_file` | We are receiving a file |
+-------------+-------------------------------------+-----------------------------------------------+
"""
def __init__(self):
# Pilot has a pusher - connects back to terminal
self.pusher = True
if prefs.LINEAGE == 'CHILD':
self.push_id = prefs.PARENTID
self.push_port = prefs.PARENTPORT
self.push_ip = prefs.PARENTIP
self.child = True
else:
self.push_id = 'T'
self.push_port = prefs.PUSHPORT
self.push_ip = prefs.TERMINALIP
self.child - False
# Store some prefs values
self.listen_port = prefs.MSGPORT
self.id = prefs.NAME.encode('utf-8')
self.pi_id = "_{}".format(self.id)
self.subject = None # Store current subject ID
self.state = None # store current pi state
self.child = False # Are we acting as a child right now?
self.parent = False # Are we acting as a parent right now?
super(Pilot_Station, self).__init__()
self.listens.update({
'STATE': self.l_state, # Confirm or notify terminal of state change
'COHERE': self.l_cohere, # Sending our temporary data table at the end of a run to compare w/ terminal's copy
'PING': self.l_ping, # The Terminal wants to know if we're listening
'START': self.l_start, # We are being sent a task to start
'STOP': self.l_stop, # We are being told to stop the current task
'PARAM': self.l_change, # The Terminal is changing some task parameter
'FILE': self.l_file, # We are receiving a file
'CONTINUOUS': self.l_continuous, # we are sending continuous data to the terminal
'CHILD': self.l_child,
'HANDSHAKE': self.l_noop,
'CALIBRATE_PORT': self.l_forward,
'CALIBRATE_RESULT': self.l_forward,
'BANDWIDTH': self.l_forward
})
###########################3
# Message/Listen handling methods
def l_noop(self, msg):
pass
def l_state(self, msg):
"""
Pilot has changed state
Stash it and alert the Terminal
Args:
msg (:class:`.Message`):
"""
# Save locally so we can respond to queries on our own, then push 'er on through
# Value will just have the state, we want to add our name
self.state = msg.value
self.push(to=self.push_id, key='STATE', value=msg.value)
def l_cohere(self, msg):
"""
Send our local version of the data table so the terminal can double check
Warning:
Not Implemented
Args:
msg (:class:`.Message`):
"""
pass
def l_ping(self, msg):
"""
The Terminal wants to know our status
Push back our current state.
Args:
msg (:class:`.Message`):
"""
# The terminal wants to know if we are alive, respond with our name and IP
# don't bother the pi
self.push(key='STATE', value=self.state, flags={'NOLOG':True})
def l_start(self, msg):
"""
We are being sent a task to start
If we need any files, request them.
Then send along to the pilot.
Args:
msg (:class:`.Message`): value will contain a dictionary containing a task
description.
"""
self.subject = msg.value['subject']
# TODO: Refactor into a general preflight check.
# First make sure we have any sound files that we need
# TODO: stim managers need to be able to return list of stimuli and this is a prime reason why
if 'stim' in msg.value.keys():
if 'sounds' in msg.value['stim'].keys():
# nested list comprehension to get value['sounds']['L/R'][0-n]
f_sounds = [sound for sounds in msg.value['stim']['sounds'].values() for sound in sounds
if sound['type'] in ['File', 'Speech']]
elif 'manager' in msg.value['stim'].keys():
# we have a manager
if msg.value['stim']['type'] == 'sounds':
f_sounds = []
for group in msg.value['stim']['groups']:
f_sounds.extend([sound for sounds in group['sounds'].values() for sound in sounds
if sound['type'] in ['File', 'Speech']])
else:
f_sounds = []
if len(f_sounds)>0:
# check to see if we have these files, if not
# def update(self, data):
# """
# Args:
# data (:class:`numpy.ndarray`): an x_width x 2 array where
# column 0 is trial number and column 1 is the value.
# """
# # data should come in as an n x 2 array,
# # 0th column - trial number (x), 1st - (y) value
# data = data.astype(np.float)
#
# self.series = pd.Series(data[...,1])
# ys = self.series.rolling(self.winsize, min_periods=0).mean().as_matrix()
#
# #print(ys)
#
# self.curve.setData(data[...,0], ys, fillLevel=0.5), request them
for sound in f_sounds:
full_path = os.path.join(prefs.SOUNDDIR, sound['path'])
if not os.path.exists(full_path):
# We ask the terminal to send us the file and then wait.
self.logger.info('REQUESTING SOUND {}'.format(sound['path']))
self.push(key='FILE', value=sound['path'])
# wait here to get the sound,
# the receiving thread will set() when we get it.
self.file_block.clear()
self.file_block.wait()
# If we're starting the task as a child, stash relevant params
if 'child' in msg.value.keys():
self.child = True
self.parent_id = msg.value['child']['parent']
self.subject = msg.value['child']['subject']
else:
self.child = False
# once we make sure we have everything, tell the Pilot to start.
self.send(self.pi_id, 'START', msg.value)
def l_stop(self, msg):
"""
Tell the pi to stop the task
Args:
msg (:class:`.Message`):
"""
self.send(self.pi_id, 'STOP')
def l_change(self, msg):
"""
The terminal is changing a parameter
Warning:
Not implemented
Args:
msg (:class:`.Message`):
"""
# TODO: Changing some task parameter from the Terminal
pass
def l_file(self, msg):
"""
We are receiving a file.
Decode from b64 and save. Set the file_block.
Args:
msg (:class:`.Message`): value will have 'path' and 'file',
where the path determines where in `prefs.SOUNDDIR` the
b64 encoded 'file' will be saved.
"""
# The file should be of the structure {'path':path, 'file':contents}
full_path = os.path.join(prefs.SOUNDDIR, msg.value['path'])
# TODO: give Message full deserialization capabilities including this one
file_data = base64.b64decode(msg.value['file'])
try:
os.makedirs(os.path.dirname(full_path))
except:
# TODO: Make more specific - only if dir already exists
pass
with open(full_path, 'wb') as open_file:
open_file.write(file_data)
self.logger.info('SOUND RECEIVED {}'.format(msg.value['path']))
# If we requested a file, some poor start fn is probably waiting on us
self.file_block.set()
def l_continuous(self, msg):
if self.child:
msg.value['pilot'] = self.parent_id
msg.value['subject'] = self.subject
msg.value['continuous'] = True
self.push(to='T', key='DATA', value=msg.value, repeat=False)
def l_child(self, msg):
"""
Telling our child to run a task.
Args:
msg ():
Returns:
"""
self.send(to=prefs.CHILDID, key='START', value=msg.value)
def l_forward(self, msg):
"""
Just forward the message to the pi.
"""
self.send(to=self.pi_id, key=msg.key, value=msg.value)
#####################################
class Net_Node(object):
"""
Drop in networking object to be given to any sub-object
behind some external-facing :class:`.Station` object.
These objects are intended to communicate locally, within a piece of hardware,
though not necessarily within the same process.
To minimize the complexity of the network topology, Net_Nodes
must communicate through a :class:`.Station` ROUTER, rather than
address each other directly.
Attributes:
context (:class:`zmq.Context`): zeromq context
loop (:class:`tornado.ioloop.IOLoop`): a tornado ioloop
sock (:class:`zmq.Socket`): Our DEALER socket.
id (str): What are we known as? What do we set our :attr:`~zmq.Socket.identity` as?
upstream (str): The identity of the ROUTER socket used by our upstream :class:`.Station` object.
port (int): The port that our upstream ROUTER socket is bound to
listens (dict): Dictionary of functions to call for different types of messages. keys match the :attr:`.Message.key`.
outbox (dict): Messages that have been sent but have not been confirmed
timers (dict): dict of :class:`threading.Timer` s that will check in on outbox messages
logger (:class:`logging.Logger`): Used to log messages and network events.
log_handler (:class:`logging.FileHandler`): Handler for logging
log_formatter (:class:`logging.Formatter`): Formats log entries as::
"%(asctime)s %(levelname)s : %(message)s"
msg_counter (:class:`itertools.count`): counter to index our sent messages
loop_thread (:class:`threading.Thread`): Thread that holds our loop. initialized with `daemon=True`
"""
context = None
loop = None
id = None
upstream = None # ID of router we connect to
port = None
listens = {}
outbox = {}
timers = {}
#connected = False
logger = None
do_logging = threading.Event()
do_logging.set()
log_handler = None
log_formatter = None
sock = None
loop_thread = None
repeat_interval = 5 # how many seconds to wait before trying to repeat a message
def __init__(self, id, upstream, port, listens, instance=True, do_logging=True):
"""
Args:
id (str): What are we known as? What do we set our :attr:`~zmq.Socket.identity` as?
upstream (str): The identity of the ROUTER socket used by our upstream :class:`.Station` object.
port (int): The port that our upstream ROUTER socket is bound to
listens (dict): Dictionary of functions to call for different types of messages.
keys match the :attr:`.Message.key`.
instance (bool): Should the node try and use the existing zmq context and tornado loop?
"""
if instance:
self.context = zmq.Context.instance()
self.loop = IOLoop.current()
else:
self.context = zmq.Context()
self.loop = IOLoop()
self.closing = threading.Event()
self.closing.clear()
# we have a few builtin listens
self.listens = {
'CONFIRM': self.l_confirm
}
# then add the rest
self.listens.update(listens)
self.id = id.encode('utf-8')
self.upstream = upstream.encode('utf-8')
self.port = int(port)
# self.connected = False
self.msg_counter = count()
# try to get a logger
if not do_logging:
self.do_logging.clear()
self.init_logging()
self.init_networking()
def __del__(self):
self.closing.set()
def init_networking(self):
"""
Creates socket, connects to specified port on localhost,
and starts the :meth:`~Net_Node.threaded_loop` as a daemon thread.
"""
self.sock = self.context.socket(zmq.DEALER)
self.sock.identity = self.id
#self.sock.probe_router = 1
# net nodes are local only
self.sock.connect('tcp://localhost:{}'.format(self.port))
# wrap in zmqstreams and start loop thread
self.sock = ZMQStream(self.sock, self.loop)
self.sock.on_recv(self.handle_listen)
self.loop_thread = threading.Thread(target=self.threaded_loop)
self.loop_thread.daemon = True
self.loop_thread.start()
self.repeat_thread = threading.Thread(target=self.repeat)
self.repeat_thread.daemon = True
self.repeat_thread.start()
#self.connected = True
def threaded_loop(self):
"""
Run in a thread, either starts the IOLoop, or if it
is already started (ie. running in another thread),
breaks.
"""
while True:
try:
self.loop.start()
except RuntimeError:
# loop already started
break
def handle_listen(self, msg):
"""
Upon receiving a message, call the appropriate listen method
in a new thread and send confirmation it was received.
Note:
Unlike :meth:`.Station.handle_listen` , only the :attr:`.Message.value`
is given to listen methods. This was initially intended to simplify these
methods, but this might change in the future to unify the messaging system.
Args:
msg (str): JSON :meth:`.Message.serialize` d message.
"""
# messages from dealers are single frames because we only have one connected partner
# and that's the dealer spec lol
msg = json.loads(msg[0])
msg = Message(**msg)
# Check if our listen was sent properly
if not msg.validate():
if self.logger:
self.logger.error('Message failed to validate:\n{}'.format(str(msg)))
return
log_this = True
if 'NOLOG' in msg.flags.keys():
log_this = False
if self.logger and self.do_logging.is_set() and log_this:
self.logger.info('{} - RECEIVED: {}'.format(self.id, str(msg)))
# if msg.key == 'CONFIRM':
# if msg.value in self.outbox.keys():
# del self.outbox[msg.value]
#
# # stop a timer thread if we have it
# if msg.value in self.timers.keys():
# self.timers[msg.value].cancel()
# del self.timers[msg.value]
#
# self.logger.info('CONFIRMED MESSAGE {}'.format(msg.value))
# else:
# Log and spawn thread to respond to listen
if isinstance(msg.to, list):
if len(msg.to) == 1:
msg.to = msg.to[0]
if isinstance(msg.to, list):
# not to us, just keep it going
_ = msg.to.pop(0)
self.send(msg=msg, repeat=False)
try:
listen_funk = self.listens[msg.key]
listen_thread = threading.Thread(target=listen_funk, args=(msg.value,))
listen_thread.start()
except KeyError:
self.logger.error('MSG ID {} - No listen function found for key: {}'.format(msg.id, msg.key))
if (msg.key != "CONFIRM") and ('NOREPEAT' not in msg.flags.keys()) :
# send confirmation
self.send(msg.sender, 'CONFIRM', msg.id)
def send(self, to=None, key=None, value=None, msg=None, repeat=True, flags = None):
"""
Send a message via our :attr:`~.Net_Node.sock` , DEALER socket.
`to` is not required. Every message
is always sent to :attr:`~.Net_Node.upstream` . `to` can be included
to send a message further up the network tree to a networking object
we're not directly connected to.
Either an already created :class:`.Message` should be passed as `msg`,
or at least `key` must be provided for a new message created
by :meth:`~.Net_Node.prepare_message` .
A :class:`threading.Timer` is created to resend the message using
:meth:`~.Net_Node.repeat` unless `repeat` is False.
Args:
to (str, list): The identity of the socket this message is to. If not included,
sent to :meth:`~.Net_Node.upstream` .
key (str): The type of message - used to select which method the receiver
uses to process this message.
value: Any information this message should contain. Can be any type, but
must be JSON serializable.
msg (`.Message`): An already created message.
repeat (bool): Should this message be resent if confirmation is not received?
"""
# send message via the dealer
# even though we only have one connection over our dealer,
# we still include 'to' in case we are sending further upstream
# but can push without 'to', just fill in with upstream id
if to is None:
to = self.upstream
if (key is None) and (msg is None):
if self.logger:
self.logger.error('Push sent without Key')
return
if not msg:
msg = self.prepare_message(to, key, value, repeat, flags)
log_this = True
if 'NOLOG' in msg.flags.keys():
log_this = False
# Make sure our message has everything
# if not msg.validate():
# if self.logger:
# self.logger.error('Message Invalid:\n{}'.format(str(msg)))
# return
# encode message
msg_enc = msg.serialize()
if not msg_enc:
self.logger.error('Message could not be encoded:\n{}'.format(str(msg)))
return
self.sock.send_multipart([bytes(self.upstream), msg_enc])
if self.logger and self.do_logging.is_set() and log_this:
self.logger.info("MESSAGE SENT - {}".format(str(msg)))
if repeat and not msg.key == "CONFIRM":
# add to outbox and spawn timer to resend
self.outbox[msg.id] = (time.time(), msg)
# self.timers[msg.id] = threading.Timer(5.0, self.repeat, args=(msg.id,))
# self.timers[msg.id].start()
def repeat(self):
"""
Periodically (according to :attr:`~.repeat_interval`) resend messages that haven't been confirmed
TTL is decremented, and messages are resent until their TTL is 0.
"""
while not self.closing.is_set():
# try to send any outstanding messages and delete if too old
# make a local copy of dict
outbox = copy(self.outbox)
if len(outbox) > 0:
for id in outbox.keys():
if outbox[id][1].ttl <= 0:
self.logger.warning('PUBLISH FAILED {} - {}'.format(id, str(outbox[id][1])))
try:
del self.outbox[id]
except KeyError:
# fine, already deleted
pass
else:
# if we didn't just put this message in the outbox...
if (time.time() - outbox[id][0]) > self.repeat_interval:
if self.do_logging.is_set():
self.logger.info('REPUBLISH {} - {}'.format(id, str(outbox[id][1])))
self.sock.send_multipart([bytes(self.upstream), outbox[id][1].serialize()])
self.outbox[id][1].ttl -= 1
# wait to do it again
time.sleep(self.repeat_interval)
def l_confirm(self, value):
"""
Confirm that a message was received.
Args:
value (str): The ID of the message we are confirming.
"""
# delete message from outbox if we still have it
# msg.value should contain the if of the message that was confirmed
try:
if value in self.outbox.keys():
del self.outbox[value]
except KeyError:
# already deleted
pass
# # stop a timer thread if we have it
# if value in self.timers.keys():
# self.timers[value].cancel()
# del self.timers[value]
if self.do_logging.is_set():
self.logger.info('CONFIRMED MESSAGE {}'.format(value))
def prepare_message(self, to, key, value, repeat, flags=None):
"""
Instantiate a :class:`.Message` class, give it an ID and
the rest of its attributes.
Args:
to (str): The identity of the socket this message is to
key (str): The type of message - used to select which method the receiver
uses to process this message.
value: Any information this message should contain. Can be any type, but
must be JSON serializable.
"""
msg = Message()
# if our name is _{something} and our upstream is {something}, replace sender with our upstream node
# upstream node should handle all incoming information to those types of nodes
#if self.id == "_{}".format(self.upstream):
# msg.sender = self.upstream
#else:
msg.sender = self.id
msg.to = to
msg.key = key
msg.value = value
msg_num = self.msg_counter.next()
msg.id = "{}_{}".format(self.id, msg_num)
if not repeat:
msg.flags['NOREPEAT'] = True
if flags:
for k, v in flags.items():
msg.flags[k] = v
return msg
def init_logging(self):
"""
Initialize logging to a timestamped file in `prefs.LOGDIR` .
The logger name will be `'node.{id}'` .
"""
timestr = datetime.datetime.now().strftime('%y%m%d_%H%M%S')
log_file = os.path.join(prefs.LOGDIR, 'NetNode_{}_{}.log'.format(self.id, timestr))
self.logger = logging.getLogger('node.{}'.format(self.id))
self.log_handler = logging.FileHandler(log_file)
self.log_formatter = logging.Formatter("%(asctime)s %(levelname)s : %(message)s")
self.log_handler.setFormatter(self.log_formatter)
self.logger.addHandler(self.log_handler)
self.logger.setLevel(logging.INFO)
self.logger.info('{} Logging Initiated'.format(self.id))
class Message(object):
"""
A formatted message.
`id`, `to`, `sender`, and `key` are required attributes,
but any other key-value pair passed on init is added to the message's attributes
and included in the message.
Can be indexed and set like a dictionary (message['key'], etc.)
Attributes:
id (str): ID that uniquely identifies a message.
format {sender.id}_{number}
to (str): ID of socket this message is addressed to
sender (str): ID of socket where this message originates
key (str): Type of message, used to select a listen method to process it
value: Body of message, can be any type but must be JSON serializable.
timestamp (str): Timestamp of message creation
ttl (int): Time-To-Live, each message is sent this many times at max,
each send decrements ttl.
"""
# TODO: just make serialization handle all attributes except Files which need to be b64 encoded first.
id = None # number of message, format {sender.id}_{number}
to = None
sender = None
key = None
# value is the only attribute that can be left None,
# ie. with signal-type messages like "STOP"
value = None
timestamp = None
flags = {}
ttl = 2 # every message starts with 2 retries. only relevant to the sender so not serialized.
def __init__(self, *args, **kwargs):
# type: (object, object) -> None
# Messages don't need to have all attributes on creation,
# but do need them to serialize
"""
Args:
*args:
**kwargs:
"""
# optional attrs should be instance attributes so they are caught by _-dict__
self.flags = {}
self.timestamp = None
self.ttl = 5
if len(args)>0:
Exception("Messages cannot be constructed with positional arguments")
for k, v in kwargs.items():
setattr(self, k, v)
# if we're not a previous message being recreated, get a timestamp for our creation
if 'timestamp' not in kwargs.keys():
self.get_timestamp()
def __str__(self):
# type: () -> str
if self.key == 'FILE' or ('MINPRINT' in self.flags.keys()):
me_string = "ID: {}; TO: {}; SENDER: {}; KEY: {}".format(self.id, self.to, self.sender, self.key)
else:
me_string = "ID: {}; TO: {}; SENDER: {}; KEY: {}; VALUE: {}".format(self.id, self.to, self.sender, self.key, self.value)
return me_string
# enable dictionary-like behavior
def __getitem__(self, key):
"""
Args:
key:
"""
return self.__dict__[key]
def __setitem__(self, key, value):
"""
Args:
key:
value:
"""
self.__dict__[key] = value
def __delitem__(self, key):
"""
Args:
key:
"""
del self.__dict__[key]
def __contains__(self, key):
"""
Args:
key:
"""
return key in self.__dict__
def __len__(self):
return len(self.__dict__)
def get_timestamp(self):
self.timestamp = datetime.datetime.now().isoformat()
def validate(self):
"""
Checks if `id`, `to`, `sender`, and `key` are all defined.
Returns:
bool (True): Does message have all required attributes set?
"""
valid = True
for prop in (self.id, self.to, self.sender, self.key):
if prop is None:
valid = False
return valid
def serialize(self):
"""
Serializes all attributes in `__dict__` using json.
Returns:
str: JSON serialized message.
"""
valid = self.validate()
if not valid:
Exception("""Message invalid at the time of serialization!\n {}""".format(str(self)))
return False
# msg = {
# 'id': self.id,
# 'to': self.to,
# 'sender': self.sender,
# 'key': self.key,
# 'value': self.value
# }
msg = self.__dict__
try:
msg_enc = json.dumps(msg)
return msg_enc
except:
return False
