Node.py

from NodeBox import NodeBox
from socket import *

class Node:
	'''handles all node operations'''
	def __init__(self):
		self.nodebox = NodeBox()
		self.socket = self.setup_socket()
		self.version = "0.0.1"

	def setup_socket(self, server_address = "127.0.0.1", server_port = 13337):
		'''returns socket that will be used for communication with clients'''
		# store server communication info in tuple for later
		server_info = (server_address, server_port)
		# create new socket, using ipv4 type address, tcp protocol
		welcome_socket = socket(AF_INET, SOCK_STREAM)
		# bind the socket to the given info (basically just setting port)
		welcome_socket.bind(server_info)
		# listen for incoming connections on the socket
		welcome_socket.listen(1)
		# return the socket for later usage
		return welcome_socket

	def socket_message_monitor(self):
		'''monitor a given socket for messages'''
		# should loop infinitely while server is running
		while True:
			# create a new communication socket if requested
			communication_socket, client_address = self.socket.accept()
			print("\n\t--------client  connected--------")
			# catch incoming messages (really just one big one)
			incoming_data = ""
			while True:
				# receive data stream
				data_catch = communication_socket.recv(2048).decode()
				# print("data_catch: ", data_catch)
				# continually add incoming data to storage string
				incoming_data += data_catch
				# wait for end of message indicator
				# print("end: ", (incoming_data[-4:]))
				if (incoming_data[-4:] == "####"):
					break
			# split up incoming data into list of messages
			# print("before delete: ", incoming_data.split("$$$$"))
			incoming_messages = incoming_data.split("$$$$")[:-1] # cut off end because it's not msg
			# collect messages for user according to public key
			collected_messages = self.nodebox.collect_messages(public_key = incoming_messages.pop(0))
			# notify number of messages received from client
			print("\n\treceived {} messages from client".format(len(incoming_messages)))
			# print("collected_messages: ", collected_messages)
			# build outgoing messages string
			outgoing_messages = ""
			for i in range(len(collected_messages)):
				outgoing_messages += collected_messages[i] + "$$$$"
			# outgoing_messages += "SEND_FINISHED" # may not be necessary when sending all
			# encode into outgoing data, add end indicator
			outgoing_data = (outgoing_messages + "####").encode()
			# send messages back
			communication_socket.send(outgoing_data)
			print("\n\tdelivered {} messages to client".format(len(collected_messages)))
			# print("done sending messages to client")
			# finish, close socket
			communication_socket.close()
			print("\n\t-------client disconnected-------\n")
			# move all received messages to NodeBox
			# print("incoming messages: ", incoming_messages)
			# print("len incoming: ", len(incoming_messages))
			for i in range(len(incoming_messages)):
				# print("adding received")
				self.nodebox.add_message(incoming_messages[i]) # add each message
			# print("done adding received")
			# print("nodebox len: ", self.nodebox.count_messages())
			# finished embrace with user, wait for next one

	def __getstate__(self):
		'''helper method that allows this class to be pickled'''
		# ref: https://stackoverflow.com/a/41754104
		pickled_self = {
			'nodebox' : self.nodebox,
			'version' : self.version
		}
		return pickled_self

	def __setstate__(self, pickled_self):
		'''helper method that allows this class to be unpickled'''
		self.nodebox = pickled_self['nodebox']
		self.socket = self.setup_socket()
		self.version = pickled_self['version']
		return

if __name__ == '__main__':
	# announce self running
	print("\n\t        Pollen Node Online        ")
	# potentially load pickled version of old node later
	# node_instance = Node()
	# pickle testing (just for testing which types have pickle issues)
	import pickler as pr
	var_name = 'node_instance'
	og_init = " = " + "Node()"
	if pr.is_pickled(var_name):
		exec(var_name + " = pr.get_pickled(var_name)")
	else:
		exec(var_name + og_init)
		pr.pickle_it(var_name, eval(var_name))
	# start monitoring socket indefinitely
	node_instance.socket_message_monitor()