# This file is part of Octopus Sensing <https://octopus-sensing.nastaran-saffar.me/>
# Copyright © Nastaran Saffaryazdi 2020
#
# Octopus Sensing is free software: you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software Foundation,
# either version 3 of the License, or (at your option) any later version.
#
# Octopus Sensing is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
# without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with Octopus Sensing.
# If not, see <https://www.gnu.org/licenses/>.
import threading
import socket
from typing import List, Optional
from octopus_sensing.common.message_creators import MessageType
from octopus_sensing.common.message import Message
from octopus_sensing.devices.device import Device
[docs]class SocketNetworkDevice(Device):
'''
This class is being used for sending triggers to other softwares using TCP-IP socket.
It works as a server socket, which sends triggers (when an event happen) to the connected clients.
For example if we have a device that record data through matlab, through this server socket, we can
send the trigger to the matlab application to mark the recorded data.
Attributes
----------
Parameters
----------
host: str
host IP address
port: str
port number
Example
-------
Creating a SocketNetworkDevice in the local machine and adding it to the device_coordinator.
By adding it to the DeviceCoordinator, it starts listening
>>> device_coordinator = DeviceCoordinator()
>>> socket_device = SocketNetworkDevice("0.0.0.0", 5002)
>>> device_coordinator.add_devices([socket_device])
Note
-----
Look at Examples/send_trigger_to_remote_device.py (server code),
Examples/matlabRecorder.m or examples/client.py (client codes)
'''
def __init__(self,
host: str,
port: str,
**kwargs):
super().__init__(**kwargs)
self._host = host
self._port = port
self._server_socket: Optional[socket.socket] = None
self.__connections: List[socket.socket] = []
self._stop_listening = False
self._trigger: Optional[str] = None
self._experiment_id: Optional[str] = None
def _accept_connections(self):
self._server_socket.listen(5)
while True:
if self._stop_listening is True:
break
try:
conn, address = self._server_socket.accept() # accept new connection
except socket.timeout:
continue
if conn is not None:
self.__connections.append(conn)
self._server_socket.shutdown(socket.SHUT_RDWR)
self._server_socket.close()
def _run(self):
self._server_socket = socket.socket() # get instance
self._server_socket.setsockopt(
socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self._server_socket.settimeout(0.5)
# bind host address and port together
self._server_socket.bind((self._host, self._port))
threading.Thread(target=self._accept_connections).start()
while True:
message = self.message_queue.get()
if message is None:
continue
if message.type == MessageType.START:
self._experiment_id = message.experiment_id
self.__set_trigger(message)
for connection in self.__connections:
threading.Thread(target=self.__send_message,
args=(connection,)).start()
elif message.type == MessageType.STOP:
self._experiment_id = message.experiment_id
self.__set_trigger(message)
for connection in self.__connections:
threading.Thread(target=self.__send_message,
args=(connection,)).start()
elif message.type == MessageType.TERMINATE:
self._trigger = "terminate"
self._stop_listening = True
for connection in self.__connections:
threading.Thread(target=self.__send_message,
args=(connection,)).start()
break
def __send_message(self, connection: socket.socket):
'''
Gets a connection and sends the trigger to it
Parameters
----------
connection: socket.socket
a socket connection
'''
assert self._trigger is not None
self._trigger += "\n"
connection.send(self._trigger.encode())
def __set_trigger(self, message: Message):
'''
Takes a message and set the trigger using its data
Parameters
----------
message: Message
a message object
'''
self._trigger = \
"{0}-{1}-{2}".format(message.type,
message.experiment_id,
str(message.stimulus_id).zfill(2))