class Peer:
INITIAL_TIME_FOR_REUNION = 8
SEND_REUNION_INTERVAL = 4
REUNION_BACK_TIMEOUT = 4 + 2 * (8 * 2.5) + 2
def __init__(self, server_ip, server_port, is_root=False, root_address=None, gui=False, interface=None):
"""
The Peer object constructor.
Code design suggestions:
1. Initialise a Stream object for our Peer.
2. Initialise a PacketFactory object.
3. Initialise our UserInterface for interaction with user commandline.
4. Initialise a Thread for handling reunion daemon.
Warnings:
1. For root Peer, we need a NetworkGraph object.
2. In root Peer, start reunion daemon as soon as possible.
3. In client Peer, we need to connect to the root of the network, Don't forget to set this connection
as a register_connection.
:param server_ip: Server IP address for this Peer that should be pass to Stream.
:param server_port: Server Port address for this Peer that should be pass to Stream.
:param is_root: Specify that is this Peer root or not.
:param root_address: Root IP/Port address if we are a client.
:type server_ip: str
:type server_port: int
:type is_root: bool
:type root_address: tuple
"""
self.has_gui = gui
self.ip = Node.parse_ip(server_ip)
self.port = server_port
self.stream = Stream(server_ip, server_port)
self.packet_factory = PacketFactory()
self.interface = interface
self.parse_interface_thread = threading.Thread(target=self.handle_user_interface_buffer, daemon=True)
self.is_root = is_root
self.root_address = root_address
self.reunion_daemon = threading.Thread(target=self.run_reunion_daemon, daemon=True)
if is_root:
root_node = GraphNode((server_ip, server_port))
self.network_graph = NetworkGraph(root_node)
if not is_root:
try:
self.stream.add_node(root_address, True)
except LostConnection as lc:
print("Couldn't connect to root")
self.father_address = None
self.send_reunion_timer = 4
self.last_reunion_back = 0
self.is_alive = False
def handle_user_interface_buffer(self):
"""
In every interval, we should parse user command that buffered from our UserInterface.
All of the valid commands are listed below:
1. Register: With this command, the client send a Register Request packet to the root of the network.
2. Advertise: Send an Advertise Request to the root of the network for finding first hope.
3. SendMessage: The following string will be added to a new Message packet and broadcast through the network.
Warnings:
1. Ignore irregular commands from the user.
2. Don't forget to clear our UserInterface buffer.
:return:
"""
if self.is_root:
while True:
while len(self.interface.buffer) > 0:
args = self.interface.buffer[0].split()
command = args[0]
self.interface.buffer = self.interface.buffer[1:]
if command.lower() == "showmap" or command.lower() == "sm":
self.network_graph.print_all()
elif command.lower() == "sendmessage":
if len(args) >= 1:
self.send_message(args[1])
time.sleep(0.1)
else:
while True:
while len(self.interface.buffer) > 0:
args = self.interface.buffer[0].split()
command = args[0]
self.interface.buffer = self.interface.buffer[1:]
if command.lower() == "register":
self.register()
elif command.lower() == "advertise":
self.advertise()
elif command.lower() == "sendmessage":
if len(args) >= 1:
self.send_message(args[1])
time.sleep(0.1)
def run(self):
"""
The main loop of the program.
Code design suggestions:
1. Parse server in_buf of the stream.
2. Handle all packets were received from our Stream server.
3. Parse user_interface_buffer to make message packets.
4. Send packets stored in nodes buffer of our Stream object.
5. ** sleep the current thread for 2 seconds **
Warnings:
1. At first check reunion daemon condition; Maybe we have a problem in this time
and so we should hold any actions until Reunion acceptance.
2. In every situation checkout Advertise Response packets; even is Reunion in failure mode or not
:return:
"""
self.reunion_daemon.start()
self.parse_interface_thread.start()
# TODO Warning 1?
while True:
packet = self.parse_in_buf()
while packet is not None:
print("PACKET HEADER:", packet.get_header())
self.handle_packet(packet)
packet = self.parse_in_buf()
try:
self.stream.send_out_buf_messages()
except LostConnection as lc:
self.handle_lost_connection(lc.node)
time.sleep(2)
def run_reunion_daemon(self):
"""
In this function, we will handle all Reunion actions.
Code design suggestions:
1. Check if we are the network root or not; The actions are identical.
2. If it's the root Peer, in every interval check the latest Reunion packet arrival time from every node;
If time is over for the node turn it off (Maybe you need to remove it from our NetworkGraph).
3. If it's a non-root peer split the actions by considering whether we are waiting for Reunion Hello Back
Packet or it's the time to send new Reunion Hello packet.
Warnings:
1. If we are the root of the network in the situation that we want to turn a node off, make sure that you will not
advertise the nodes sub-tree in our GraphNode.
2. If we are a non-root Peer, save the time when you have sent your last Reunion Hello packet; You need this
time for checking whether the Reunion was failed or not.
3. For choosing time intervals you should wait until Reunion Hello or Reunion Hello Back arrival,
pay attention that our NetworkGraph depth will not be bigger than 8. (Do not forget main loop sleep time)
4. Suppose that you are a non-root Peer and Reunion was failed, In this time you should make a new Advertise
Request packet and send it through your register_connection to the root; Don't forget to send this packet
here, because in the Reunion Failure mode our main loop will not work properly and everything will be got stock!
:return:
"""
interval = 0.1
if self.is_root:
while True:
self.network_graph.remove_all_expired_nodes()
time.sleep(interval)
else:
while True:
self.send_reunion_timer -= interval
if self.send_reunion_timer <= 0 and self.is_alive:
self.send_reunion()
self.send_reunion_timer = Peer.SEND_REUNION_INTERVAL
if time.time() - self.last_reunion_back > Peer.REUNION_BACK_TIMEOUT and self.is_alive:
print("Time:", time.time(), "Last:", self.last_reunion_back, "Timeout!!")
self.timeout()
time.sleep(interval)
def send_broadcast_packet(self, broadcast_packet):
"""
For setting broadcast packets buffer into Nodes out_buff.
Warnings:
1. Don't send Message packets through register_connections.
:param broadcast_packet: The packet that should be broadcast through the network.
:type broadcast_packet: Packet
:return:
"""
for node in self.stream.get_nodes():
if not node.is_register:
self.stream.add_message_to_out_buff(node.get_server_address(), broadcast_packet.get_buf())
def handle_packet(self, packet):
"""
This function act as a wrapper for other handle_###_packet methods to handle the packet.
Code design suggestion:
1. It's better to check packet validation right now; For example Validation of the packet length.
:param packet: The arrived packet that should be handled.
:type packet Packet
"""
# print("A New Packet Received!")
# print("Header: ", packet.get_header())
# print("Body: ", packet.get_body())
# TODO: packet validation
if packet.get_type() == Type.register:
self.__handle_register_packet(packet)
elif packet.get_type() == Type.advertise:
self.__handle_advertise_packet(packet)
elif packet.get_type() == Type.join:
self.__handle_join_packet(packet)
elif packet.get_type() == Type.message:
self.__handle_message_packet(packet)
elif packet.get_type() == Type.reunion:
self.__handle_reunion_packet(packet)
def __check_registered(self, source_address):
"""
If the Peer is the root of the network we need to find that is a node registered or not.
:param source_address: Unknown IP/Port address.
:type source_address: tuple
:return:
"""
# TODO: ba rakhsha check konam
return self.network_graph.is_registered(source_address)
def __handle_advertise_packet(self, packet):
"""
For advertising peers in the network, It is peer discovery message.
Request:
We should act as the root of the network and reply with a neighbour address in a new Advertise Response packet.
Response:
When an Advertise Response packet type arrived we should update our parent peer and send a Join packet to the
new parent.
Code design suggestion:
1. Start the Reunion daemon thread when the first Advertise Response packet received.
2. When an Advertise Response message arrived, make a new Join packet immediately for the advertised address.
Warnings:
1. Don't forget to ignore Advertise Request packets when you are a non-root peer.
2. The addresses which still haven't registered to the network can not request any peer discovery message.
3. Maybe it's not the first time that the source of the packet sends Advertise Request message. This will happen
in rare situations like Reunion Failure. Pay attention, don't advertise the address to the packet sender
sub-tree.
4. When an Advertise Response packet arrived update our Peer parent for sending Reunion Packets.
:param packet: Arrived advertise packet
:type packet Packet
:return:
"""
body = packet.get_body()
type = body[0:3]
print("RCVD packet:", packet.body)
if type == "REQ" and self.is_root:
ip = packet.get_source_server_ip()
port = int(packet.get_source_server_port())
parent_address = self.network_graph.find_parent_and_assign(ip, port)
if parent_address is None:
# Ignore, the node is not registered
return
else:
print("Answering Ad REQ of", ip, port, "Parent:", parent_address[0], parent_address[1])
res = self.packet_factory.new_advertise_packet("RES", (self.ip, self.port), parent_address)
self.stream.add_message_to_out_buff((ip, port), res.get_buf())
elif type == "RES" and (not self.is_root):
server_ip = body[3:18]
server_port = int(body[18:23])
print("Proposed Parent:", server_ip, server_port)
# remove former parent node
if self.father_address is not None:
try:
parent_node = self.stream.get_node_by_server(self.father_address[0], self.father_address[1],
only_not_registers=True)
self.stream.remove_node(parent_node)
except ValueError as e:
print(repr(e))
traceback.print_exc()
self.father_address = (server_ip, server_port)
try:
self.stream.add_node(self.father_address)
res = self.packet_factory.new_join_packet((self.ip, self.port))
self.stream.add_message_to_out_buff(self.father_address, res.get_buf())
self.is_alive = True
if self.has_gui:
self.interface.set_alive(self.is_alive)
self.last_reunion_back = time.time() + Peer.INITIAL_TIME_FOR_REUNION
except LostConnection as lc:
print("Coudn't connect to father")
def __handle_register_packet(self, packet):
"""
For registration a new node to the network at first we should make a Node with stream.add_node for'sender' and
save it.
Code design suggestion:
1.For checking whether an address is registered since now or not you can use SemiNode object except Node.
Warnings:
1. Don't forget to ignore Register Request packets when you are a non-root peer.
:param packet: Arrived register packet
:type packet Packet
:return:
"""
body = packet.get_body()
type = body[0:3]
if type == "REQ" and self.is_root:
ip = body[3:18]
port = int(body[18:23])
print("Registering ", ip, port)
self.network_graph.register_node(ip, port)
try:
self.stream.add_node((ip, port), set_register_connection=True)
res = self.packet_factory.new_register_packet("RES", (self.ip, self.port))
self.stream.add_message_to_out_buff((ip, port), res.get_buf())
except LostConnection as lc:
print("Coudn't connect to registered node")
elif type == "RES" and (not self.is_root):
if body[3:6] == "ACK":
print("Register ACKed")
def __check_neighbour(self, address):
"""
It checks is the address in our neighbours array or not.
:param address: Unknown address
:type address: tuple
:return: Whether is address in our neighbours or not.
:rtype: bool
"""
return self.stream.get_node_by_server(address[0], address[1]) is not None
def __handle_message_packet(self, packet):
"""
Only broadcast message to the other nodes.
Warnings:
1. Do not forget to ignore messages from unknown sources.
2. Make sure that you are not sending a message to a register_connection.
:param packet: Arrived message packet
:type packet Packet
:return:
"""
sender = packet.get_source_server_address()
if not self.__check_neighbour(sender):
print("Ignored a Message from unknown source")
return
body = packet.get_body()
if self.has_gui:
self.interface.append_message(body)
else:
print("Message Received:\n", body)
packet = self.packet_factory.new_message_packet(body, (self.ip, self.port))
for node in self.stream.get_nodes():
if node.get_server_address() != sender and (not node.is_register):
self.stream.add_message_to_out_buff(node.get_server_address(), packet.get_buf())
def __handle_reunion_packet(self, packet):
"""
In this function we should handle Reunion packet was just arrived.
Reunion Hello:
If you are root Peer you should answer with a new Reunion Hello Back packet.
At first extract all addresses in the packet body and append them in descending order to the new packet.
You should send the new packet to the first address in the arrived packet.
If you are a non-root Peer append your IP/Port address to the end of the packet and send it to your parent.
Reunion Hello Back:
Check that you are the end node or not; If not only remove your IP/Port address and send the packet to the next
address, otherwise you received your response from the root and everything is fine.
Warnings:
1. Every time adding or removing an address from packet don't forget to update Entity Number field.
2. If you are the root, update last Reunion Hello arrival packet from the sender node and turn it on.
3. If you are the end node, update your Reunion mode from pending to acceptance.
:param packet: Arrived reunion packet
:return:
"""
body = packet.get_body()
type = body[0:3]
number_of_entries = int(body[3:5])
entries = []
for i in range(number_of_entries):
entry_ip = body[5 + i * 20: 5 + i * 20 + 15]
entry_port = int(body[5 + i * 20 + 15: 5 + i * 20 + 20])
entries.append((entry_ip, entry_port))
if number_of_entries < 1:
print("Warning: Invalid Reunion Packet")
return
if type == "REQ":
if self.is_root:
self.network_graph.update_latest_reunion_time(entries[0])
first_hop = entries[-1]
entries.reverse()
res = self.packet_factory.new_reunion_packet("RES", (self.ip, self.port), entries)
self.stream.add_message_to_out_buff(first_hop, res.get_buf())
else:
if not self.is_alive:
return
entries.append((self.ip, self.port))
res = self.packet_factory.new_reunion_packet("REQ", (self.ip, self.port), entries)
self.stream.add_message_to_out_buff(self.father_address, res.get_buf())
if type == "RES":
if self.is_root:
print("Warning: Invalid Reunion Packet")
return
if (self.ip, self.port) == entries[0]:
self.last_reunion_back = time.time()
return
if (self.ip, self.port) != entries[-1]:
print("Warning: Invalid Reunion Packet")
return
entries = entries[0:-1]
next_hop = entries[-1]
res = self.packet_factory.new_reunion_packet("RES", (self.ip, self.port), entries)
self.stream.add_message_to_out_buff(next_hop, res.get_buf())
def __handle_join_packet(self, packet):
"""
When a Join packet received we should add a new node to our nodes array.
In reality, there is a security level that forbids joining every node to our network.
:param packet: Arrived register packet.
:type packet Packet
:return:
"""
new_address = packet.get_source_server_address()
try:
self.stream.add_node(new_address, set_register_connection=False)
except LostConnection as lc:
print("Coudn't connect to joined node from", new_address)
def __get_neighbour(self, sender):
"""
Finds the best neighbour for the 'sender' from the network_nodes array.
This function only will call when you are a root peer.
Code design suggestion:
1. Use your NetworkGraph find_live_node to find the best neighbour.
:param sender: Sender of the packet
:return: The specified neighbour for the sender; The format is like ('192.168.001.001', '05335').
"""
return self.network_graph.find_parent_and_assign(sender[0], sender[1])
def parse_in_buf(self):
buffer = self.stream.read_in_buf()
header_size = 20
if len(buffer) < header_size:
return None
packet = Packet(buf=buffer[0:20])
packet_length = packet.get_length()
if len(buffer) < packet_length:
return None
packet = Packet(buf=buffer[0:packet_length])
self.stream.delete_buffer(packet_length)
return packet
def register(self):
print("Register Command!")
if self.is_root:
return
req = self.packet_factory.new_register_packet("REQ", (self.ip, self.port), (self.ip, self.port))
self.stream.add_message_to_out_buff(self.root_address, req.get_buf())
def advertise(self):
print("Advertisement Command")
req = self.packet_factory.new_advertise_packet("REQ", (self.ip, self.port))
self.stream.add_message_to_out_buff(self.root_address, req.get_buf())
pass
def send_message(self, message):
print("Message Command! Message:", message)
packet = self.packet_factory.new_message_packet(message, (self.ip, self.port))
self.send_broadcast_packet(packet)
def send_reunion(self):
reunion_packet = self.packet_factory.new_reunion_packet("REQ", (self.ip, self.port), [(self.ip, self.port)])
self.stream.add_message_to_out_buff(self.father_address, reunion_packet.get_buf())
def timeout(self):
self.is_alive = False
if self.has_gui:
self.interface.set_alive(self.is_alive)
self.advertise()
def handle_lost_connection(self, node):
self.stream.remove_node(node)
print("Connection with ", node.get_server_address(), " lost")
if node.get_server_address() == self.father_address:
print("Connection with father lost")
self.timeout()
class Peer(threading.Thread):
def __init__(self, server_ip, server_port, is_root, ui, root_address=None):
"""
The Peer object constructor.
Code design suggestions:
1. Initialise a Stream object for our Peer.
2. Initialise a PacketFactory object.
3. Initialise our UserInterface for interaction with user commandline.
4. Initialise a Thread for handling reunion daemon.
Warnings:
1. For root Peer, we need a NetworkGraph object.
2. In root Peer, start reunion daemon as soon as possible.
3. In client Peer, we need to connect to the root of the network, Don't forget to set this connection
as a register_connection.
:param server_ip: Server IP address for this Peer that should be pass to Stream.
:param server_port: Server Port address for this Peer that should be pass to Stream.
:param is_root: Specify that is this Peer root or not.
:param root_address: Root IP/Port address if we are a client.
:type server_ip: str
:type server_port: int
:type is_root: bool
:type root_address: tuple
"""
super().__init__()
self.ui_buffer = queue.Queue()
self.stream = Stream(server_ip, server_port, ui)
self.ip = Node.parse_ip(server_ip)
self.port = Node.parse_port(str(server_port))
self.address = (self.ip, int(self.port))
self.setDaemon(True)
self.ui = ui
self.is_root = is_root
self.root_address = self.address
if not is_root:
self.root_address = root_address
self.children = []
self.is_reunion_running = False
self.parent = None
self.is_connected = False
# self.reunion_timer = ReunionTimer(self)
self.graph = NetworkGraph(GraphNode(self.root_address))
if not self.is_root:
print('making the shit')
self.stream.add_node(self.root_address, True)
self.r_h_b_received = True
self.since_last = 0
self.timer = Timer(self)
self.timer.start()
self.stop = False
def start_user_interface(self):
"""
For starting UserInterface thread.
:return:
"""
# in our code userinterface starts this shit
pass
def add_command(self, command):
self.ui_buffer.put(command)
def handle_user_interface_buffer(self):
"""
In every interval, we should parse user command that buffered from our UserInterface.
All of the valid commands are listed below:
1. Register: With this command, the client send a Register Request packet to the root of the network.
2. Advertise: Send an Advertise Request to the root of the network for finding first hope.
3. SendMessage: The following string will be added to a new Message packet and broadcast through the network.
Warnings:
1. Ignore irregular commands from the user.
2. Don't forget to clear our UserInterface buffer.
:return:
"""
while not self.ui_buffer.empty():
command = self.ui_buffer.get()
command = str(command)
s = (command.split(' '))
if s[0] == 'send_message':
print('send message')
self.send_message(command[13:])
pass
elif s[0] == 'join':
print('join')
self.send_join()
pass
elif s[0] == 'register':
print('send register')
self.send_register()
pass
elif s[0] == 'advertise':
print('advertise')
self.send_advertise()
elif s[0] == 'regi':
print('registered:')
for reged in self.graph.registered:
print(reged.get_address()[0])
print(reged.get_address()[1])
elif s[0] == 're':
self.send_reunion()
pass
elif s[0] == 'par':
print(self.parent)
elif s[0] == 'ch':
for address in self.children:
print(address)
pass
def send_advertise(self):
if not self.is_root:
pkt = PacketFactory.new_advertise_packet('REQ', self.address)
self.stream.add_message_to_out_buff(self.root_address, pkt)
pass
def send_register(self):
if not self.is_root:
pkt = PacketFactory.new_register_packet('REQ', self.address,
self.address)
# self.ui.display_pkt(PacketFactory.parse_buffer(pkt))
self.stream.add_message_to_out_buff(self.root_address, pkt)
pass
def send_message(self, s):
if not self.is_connected:
return
print('sending mesaage to:')
pkt = PacketFactory.new_message_packet(s, self.address)
for address in self.children:
print(address)
self.stream.add_message_to_out_buff(address, pkt)
if not (self.is_root) and (self.address is not None):
print(self.parent)
self.stream.add_message_to_out_buff(self.parent, pkt)
pass
def send_join(self):
pkt = PacketFactory.new_join_packet(self.address)
self.stream.add_message_to_out_buff(self.parent, pkt)
self.is_connected = True
pass
def run(self):
"""
The main loop of the program.
Code design suggestions:
1. Parse server in_buf of the stream.
2. Handle all packets were received from our Stream server.
3. Parse user_interface_buffer to make message packets.
4. Send packets stored in nodes buffer of our Stream object.
5. ** sleep the current thread for 2 seconds **
Warnings:
1. At first check reunion daemon condition; Maybe we have a problem in this time
and so we should hold any actions until Reunion acceptance.
2. In every situation checkout Advertise Response packets; even is Reunion in failure mode or not
:return:
"""
while not self.stop:
# if not self.is_connected:
# self.stream.clear_in_buff()
# self.stream.clear_out_buff()
# self.stream.clear_not_reg_nodes()
print('we R in loop')
self.read_stream_in_buffer()
self.handle_user_interface_buffer()
self.stream.send_out_buf_messages()
time.sleep(2)
def read_stream_in_buffer(self):
buffers = self.stream.read_in_buf()
for buffer in buffers:
print(buffer)
packet = PacketFactory.parse_buffer(buffer)
if packet is None:
continue
if packet.length + 20 != len(buffer):
continue
self.handle_packet(packet)
self.stream.clear_in_buff()
def run_reunion_daemon(self):
"""
In this function, we will handle all Reunion actions.
Code design suggestions:
1. Check if we are the network root or not; The actions are identical.
2. If it's the root Peer, in every interval check the latest Reunion packet arrival time from every node;
If time is over for the node turn it off (Maybe you need to remove it from our NetworkGraph).
3. If it's a non-root peer split the actions by considering whether we are waiting for Reunion Hello Back
Packet or it's the time to send new Reunion Hello packet.
Warnings:
1. If we are the root of the network in the situation that we want to turn a node off, make sure that you will not
advertise the nodes sub-tree in our GraphNode.
2. If we are a non-root Peer, save the time when you have sent your last Reunion Hello packet; You need this
time for checking whether the Reunion was failed or not.
3. For choosing time intervals you should wait until Reunion Hello or Reunion Hello Back arrival,
pay attention that our NetworkGraph depth will not be bigger than 8. (Do not forget main loop sleep time)
4. Suppose that you are a non-root Peer and Reunion was failed, In this time you should make a new Advertise
Request packet and send it through your register_connection to the root; Don't forget to send this packet
here, because in the Reunion Failure mode our main loop will not work properly and everything will be got stock!
:return:
"""
# self.reunion_timer.start()
pass
def send_broadcast_packet(self, broadcast_packet):
"""
For setting broadcast packets buffer into Nodes out_buff.
Warnings:
1. Don't send Message packets through register_connections.
:param broadcast_packet: The packet that should be broadcast through the network.
:type broadcast_packet: Packet
:return:
"""
nodes = self.stream.get_not_register_nodes()
for node in nodes:
self.stream.add_message_to_out_buff(node.get_server_address(),
broadcast_packet)
pass
def handle_packet(self, packet):
"""
This function act as a wrapper for other handle_###_packet methods to handle the packet.
Code design suggestion:
1. It's better to check packet validation right now; For example Validation of the packet length.
:param packet: The arrived packet that should be handled.
:type packet Packet
"""
print('this is handle packet')
if not self.chenck_in_neighbour(packet.get_source_server_address()):
return
self.ui.display_pkt(packet)
if packet.type == 1:
self.__handle_register_packet(packet)
return
elif packet.type == 2:
self.__handle_advertise_packet(packet)
pass
elif packet.type == 3:
self.__handle_join_packet(packet)
pass
elif packet.type == 4:
self.__handle_message_packet(packet)
pass
elif packet.type == 5:
self.__handle_reunion_packet(packet)
pass
pass
def chenck_in_neighbour(self, address):
if not self.is_connected:
return False
if self.address_equal(self.parent, address):
return True
for c in self.children:
if self.address_equal(c, address):
return True
return False
def __check_registered(self, source_address):
"""
If the Peer is the root of the network we need to find that is a node registered or not.
:param source_address: Unknown IP/Port address.
:type source_address: tuple
:return:
"""
return self.graph.is_registered(source_address)
pass
def __handle_advertise_packet(self, packet):
"""
For advertising peers in the network, It is peer discovery message.
Request:
We should act as the root of the network and reply with a neighbour address in a new Advertise Response packet.
Response:
When an Advertise Response packet type arrived we should update our parent peer and send a Join packet to the
new parent.
Code design suggestion:
1. Start the Reunion daemon thread when the first Advertise Response packet received.
2. When an Advertise Response message arrived, make a new Join packet immediately for the advertised address.
Warnings:
1. Don't forget to ignore Advertise Request packets when you are a non-root peer.
2. The addresses which still haven't registered to the network can not request any peer discovery message.
3. Maybe it's not the first time that the source of the packet sends Advertise Request message. This will happen
in rare situations like Reunion Failure. Pay attention, don't advertise the address to the packet sender
sub-tree.
4. When an Advertise Response packet arrived update our Peer parent for sending Reunion Packets.
:param packet: Arrived register packet
:type packet Packet
:return:
"""
if (packet.body[0:3] == 'RES') and (not self.is_root):
self.children.clear()
self.stream.remove_not_reg_nodes()
self.parent = Node.parse_address(
(packet.body[3:18], packet.body[18:23]))
succ = self.stream.add_node(self.parent)
if not succ:
return
join = PacketFactory.new_join_packet(self.address)
self.stream.add_message_to_out_buff(self.parent, join)
self.is_connected = True
self.r_h_b_received = True
self.since_last = 0
# now we are connected
elif (packet.body[0:3] == 'REQ') and (self.is_root):
if not self.graph.is_registered(
packet.get_source_server_address()):
return
address = self.graph.find_live_node(
packet.get_source_server_address()).get_address()
if address is None:
return
self.graph.add_node(packet.sender_ip, packet.sender_port, address)
res_pkt = PacketFactory.new_advertise_packet(
'RES', self.address, address)
self.stream.add_message_to_out_buff(
packet.get_source_server_address(), res_pkt)
pass
def __handle_register_packet(self, packet):
"""
For registration a new node to the network at first we should make a Node with stream.add_node for'sender' and
save it.
Code design suggestion:
1.For checking whether an address is registered since now or not you can use SemiNode object except Node.
Warnings:
1. Don't forget to ignore Register Request packets when you are a non-root peer.
:param packet: Arrived register packet
:type packet Packet
:return:
"""
source_address = (packet.sender_ip, packet.sender_port)
if self.is_root and (not self.__check_registered(source_address)):
self.graph.register(source_address)
self.stream.add_node(source_address, True)
res_pkt = PacketFactory.new_register_packet('RES', self.address)
self.stream.add_message_to_out_buff(source_address, res_pkt)
pass
def __check_neighbour(self, address):
"""
It checks is the address in our neighbours array or not.
:param address: Unknown address
:type address: tuple
:return: Whether is address in our neighbours or not.
:rtype: bool
"""
if (address[0] == self.parent[0]) & (address[1] == self.parent[1]):
return True
for add in self.children:
if (address[0] == add[0]) & (address[1] == add[1]):
return True
return False
pass
def __handle_message_packet(self, packet):
"""
Only broadcast message to the other nodes.
Warnings:
1. Do not forget to ignore messages from unknown sources.
2. Make sure that you are not sending a message to a register_connection.
:param packet: Arrived message packet
:type packet Packet
:return:
"""
if not self.child_or_parent(packet.get_source_server_address()):
return
message = packet.get_body()
self.ui.display_message('Broadcast Message: ' + message)
res_pkt = PacketFactory.new_message_packet(message, self.address)
print('trying to send packet to:')
for address in self.children:
if not self.address_equal(address,
packet.get_source_server_address()):
self.stream.add_message_to_out_buff(address, res_pkt)
print(address)
if (not self.is_root) and (self.parent is not Node):
if self.address_equal(self.parent,
packet.get_source_server_address()):
return
print(self.parent)
self.stream.add_message_to_out_buff(self.parent, res_pkt)
def address_equal(self, address1, address2):
address1 = Node.parse_address(address1)
address2 = Node.parse_address(address2)
return (address1[0] == address2[0]) and (address1[1] == address2[1])
def child_or_parent(self, input):
for address in self.children:
if self.address_equal(input, address):
return True
if self.parent is not Node:
if self.address_equal(input, self.parent):
return True
return False
pass
def __handle_reunion_packet(self, packet):
"""
In this function we should handle Reunion packet was just arrived.
Reunion Hello:
If you are root Peer you should answer with a new Reunion Hello Back packet.
At first extract all addresses in the packet body and append them in descending order to the new packet.
You should send the new packet to the first address in the arrived packet.
If you are a non-root Peer append your IP/Port address to the end of the packet and send it to your parent.
Reunion Hello Back:
Check that you are the end node or not; If not only remove your IP/Port address and send the packet to the next
address, otherwise you received your response from the root and everything is fine.
Warnings:
1. Every time adding or removing an address from packet don't forget to update Entity Number field.
2. If you are the root, update last Reunion Hello arrival packet from the sender node and turn it on.
3. If you are the end node, update your Reunion mode from pending to acceptance.
:param packet: Arrived reunion packet
:return:
"""
nodes = PacketFactory.parse_reunion_packet_body(packet.body)
if self.is_root:
if packet.body[0:3] == 'RES':
return
self.graph.reunion_arrived(nodes[0])
nodes.reverse()
res_pkt = PacketFactory.new_reunion_packet('RES', self.address,
nodes)
self.stream.add_message_to_out_buff(
packet.get_source_server_address(), res_pkt)
print('hello back sent to')
print(packet.get_source_server_address())
return
else:
if packet.body[0:3] == 'REQ':
nodes.append(self.address)
res_pkt = PacketFactory.new_reunion_packet(
'REQ', self.address, nodes)
self.stream.add_message_to_out_buff(self.parent, res_pkt)
return
else:
nodes = PacketFactory.parse_reunion_packet_body(packet.body)
if not self.address_equal(nodes[0], self.address):
return
if len(nodes) == 1:
# print('bla bla bla bla bla bla')
self.reunion_back_arrived()
return
# print('kiiiiir')
nodes.remove(nodes[0])
res_pkt = PacketFactory.new_reunion_packet(
'RES', self.address, nodes)
self.stream.add_message_to_out_buff(nodes[0], res_pkt)
return
pass
def __handle_join_packet(self, packet):
"""
When a Join packet received we should add a new node to our nodes array.
In reality, there is a security level that forbids joining every node to our network.
:param packet: Arrived register packet.
:type packet Packet
:return:
"""
self.children.append((packet.sender_ip, packet.sender_port))
self.stream.add_node((packet.sender_ip, packet.sender_port))
pass
def __get_neighbour(self, sender):
"""
Finds the best neighbour for the 'sender' from the network_nodes array.
This function only will call when you are a root peer.
Code design suggestion:
1. Use your NetworkGraph find_live_node to find the best neighbour.
:param sender: Sender of the packet
:return: The specified neighbour for the sender; The format is like ('192.168.001.001', '05335').
"""
pass
# def reunion_failed_notify(self):
# self.reunion_timer.stop()
# self.is_connected = False
# pass
def send_reunion(self):
if not self.is_connected:
return
pkt = PacketFactory.new_reunion_packet('REQ', self.address,
[self.address])
self.stream.add_message_to_out_buff(self.parent, pkt)
self.since_last = 0
self.r_h_b_received = False
def disconnect(self):
self.is_connected = False
self.parent = None
self.stream.remove_not_reg_nodes()
self.stream.clear_in_buff()
# maybe we need some more shit
def sec_passed(self):
print('........')
print(self.is_root)
print(self.is_connected)
print(self.r_h_b_received)
print(self.since_last)
print('........')
self.ui.update_stats()
if self.is_connected and (not self.is_root):
self.since_last += 1
if (not self.r_h_b_received) and (self.since_last > 50):
self.disconnect()
return
elif (self.r_h_b_received) and (self.since_last > 4):
self.send_reunion()
if self.is_root:
self.graph.increment_time()
pass
def reunion_back_arrived(self):
self.r_h_b_received = True
def exit(self):
self.timer.stop = True
self.stream.remove_not_reg_nodes()