rebased networking onto main with new name

# Conflicts:
#	pypong/networking/gui.py
#	pypong/networking/host.py

pynpong/networking/client.py

@@ -0,0 +1,121 @@
+"""
+Networking client to connect to a server and find server hosts
+"""
+import ipaddress
+import random
+
+import psutil
+import socket
+
+SERVER_PORT = 29987
+SERVER_BUFFER = 1024
+SCAN_TIMEOUT = 3
+
+
+class InterfaceInfo:
+    """
+    Class used for storing interface information to make it easier to use
+    """
+
+    def __init__(self, interface_name, network):
+        self.interface_name = interface_name
+        self.network = network
+
+    def __str__(self):
+        return 'Interface:{0}, Network:{1}'.format(self.interface_name, self.network)
+
+    def __repr__(self):
+        return '(Interface:{0}, Network:{1})'.format(self.interface_name, self.network)
+
+
+def request_server_info(server_ip, server_port):
+    """
+    Request server info from a PyPong server given an IP and a port
+
+    :param server_ip: Server IP to request info from
+    :param server_port: Port to connect to server on
+    :return: response given by server (or lack thereof)
+    """
+    request = 'PYPONGREQ;SVRINFO'
+
+    udp_client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    # Timeout is set to SCAN_TIMEOUT plus a random number between 0 and SCAN_TIMEOUT so that threads can
+    # start asynchronously to avoid a lot of requests being sent to machines at once
+    # Average time is SCAN_TIMEOUT*1.5
+    udp_client_socket.settimeout(SCAN_TIMEOUT + (SCAN_TIMEOUT * random.random()))
+    try:
+        udp_client_socket.sendto(str.encode(request, 'UTF-8'), (server_ip, server_port))
+    except OSError:
+        pass
+    try:
+        server_response = udp_client_socket.recvfrom(SERVER_BUFFER)[0].decode('UTF-8')
+    except TimeoutError:
+        server_response = '{0};TIMEOUT'.format(server_ip)
+    except UnicodeDecodeError:
+        server_response = '{0};MANGLED_RESPONSE'.format(server_ip)
+
+    udp_client_socket.close()
+    return server_response
+
+
+def get_interface_info():
+    """
+    Gets information using psutil about the current machine's interfaces and their networks. This only works for IPv4
+    networks and will not return any data in regard to IPv6 links.
+
+    :return: List of InterfaceInfo objects containing information about all interfaces on the current machine excluding
+    the loopback interface (lo or 127.0.0.1)
+    """
+    raw_interface_data = psutil.net_if_addrs()
+    interface_data = []
+
+    for interface in raw_interface_data:
+        # Extract needed information from psutil and put it into a InterfaceInfo object
+        address = (raw_interface_data.get(interface)[0]).address
+        cidr_suffix = ipaddress.IPv4Network('{0}/{1}'.format(address, raw_interface_data.get(interface)[0].netmask),
+                                            strict=False).prefixlen
+
+        # Do not add the loopback interface or IPv6 interfaces
+        if ':' not in address and address != '127.0.0.1':
+            interface_data.append(InterfaceInfo(interface, '{0}/{1}'.format(address, cidr_suffix)))
+    return interface_data
+
+
+def get_ips_from_network(network):
+    """
+    Generate a list of IP addresses given an address in CIDR notation. This works from smallest to largest, meaning that
+    it builds a list starting at <ADDRESS>/32 (aka just the current machine) decrementing the CIDR by 1 until the
+    correct subnet is reached.
+
+    :param network:
+    :return:
+    """
+    network_split = network.split('/')
+    address = network_split[0]
+    cidr = int(network_split[1])
+    all_addresses = []
+
+    test_cidr = 32  # Start with the machine itself
+    while test_cidr >= cidr:
+        # Generate all addresses inside the current subnet given by 'address/test_cidr'
+        current_addresses = [str(ip) for ip in ipaddress.IPv4Network('{0}/{1}'.format(address, test_cidr),
+                                                                     strict=False)]
+
+        # Do not add the address again if it is already in the list of all addresses
+        for test_address in current_addresses:
+            if test_address not in all_addresses:
+                all_addresses.append(test_address)
+        test_cidr -= 1
+
+    return all_addresses
+
+
+def check_ip(ip_address):
+    """
+    Check a single IP address for a running game server
+
+    :param ip_address: IP address to check
+    :return: response of the server (or timeout if none)
+    """
+    response = request_server_info(ip_address, SERVER_PORT)
+    return response

pynpong/networking/gui.py

@@ -2,19 +2,29 @@
 Starting launcher of the game. This is where you host new games or join other ones.
 """
 import tkinter as tk
+import concurrent.futures
+import pypong.networking.client as client
 
 global running
 
+# Don't allow any more than this number of threads when looking for games
+# Can cripple a network at high numbers, 128 is recommended (can scan a /24 network in ~9 seconds on average)
+# Higher range subnets will exponentially take more time to finish (/16 would take ~38.4 minutes at 128 req/s)
+MAX_SCAN_REQUESTS = 128
 
 def main():
     """
     Runs the game launcher.
     """
+
+    # Executor used for scanning local network for servers
+    executor = concurrent.futures.ThreadPoolExecutor(max_workers=MAX_SCAN_REQUESTS)
+
     main_window = tk.Tk()
     main_window.title('PynPong Launcher')
     main_window.resizable(width=False, height=False)
 
-    main_window.geometry('500x250')
+    main_window.geometry('500x300')
 
     def quit_launcher():
         """
@@ -22,20 +32,96 @@ def main():
         """
         global running
         running = False
+        # Stop executor from creating new scanning tasks
+        executor.shutdown(wait=False, cancel_futures=True)
 
-    def get_games():
+    def check_game(game_ip):
         """
-        Refresh the games list.
+        Checks to see if there is a game bein ghosted at a given IP
+
+        :param game_ip: IP address to check for a host
+        :return: Response from the server (or timeout if nothing found)
+        """
+        result = client.check_ip(game_ip)
+        return result
+
+    def get_games(network):
+        """
+        Refreshes the game list.
+
+        :param network: The network to scan for games on
         """
         listbox.delete(0, tk.END)
-        listbox.insert(0, 'Searching for games...')
-        # Networking code will go here eventually
+        listbox.insert(0, ' Building IP range...')
+        main_window.update()
+
+        possible_ips = client.get_ips_from_network(network.get().split(' ')[0])
+
+        listbox.delete(0, tk.END)
+        listbox.insert(0, 'this might take some time...')
+        listbox.insert(0, 'Refreshing server listing,')
+        main_window.update()
+
+        futures = []
+        # Use the executor to create threads to search for games
+        for ip in possible_ips:
+            future = executor.submit(check_game, ip)
+            futures.append(future)
+
+        game_found = False
+
+        for future in futures:
+            result = future.result()
+
+            if 'PYPONGRST;SVRINFO' in result:  # Check to make sure response has the right header and type
+                raw_response = result.split(';')  # Split response by block (denoted by semicolons)
+                response = []
+
+                # Split up each block by chunks (<COMMAND>:<RESPONSE>)
+                # e.g. the block 'NAME:Nicholas Dyer' -> ['NAME', 'Nicholas Dyer']
+                for block in raw_response:
+                    chunks = block.split(':')
+                    for chunk in chunks:
+                        response.append(chunk)
+
+                # Make sure the response has the NAME command
+                if 'NAME' in response:
+                    # Session name is the next index after the command
+                    session_name = response[response.index('NAME') + 1]
+                    if not game_found:  # If this is the first game found, clear out the list
+                        listbox.delete(0, tk.END)
+                        game_found = True
+                    listbox.insert(0, session_name)
+            main_window.update()  # Update screen while finding games (laggy, but works)
+
+        if not game_found:
+            listbox.delete(0, tk.END)
+            listbox.insert(0, 'No games found!')
+
+    def get_addresses():
+        """
+        Get the current machine's local interfaces and their corresponding addresses in CIDR notation
+
+        :return: Address in CIDR notation along with the interface
+
+        Example:
+
+        ['172.20.126.4/24 [eth0]', 192.168.2.43/16 [wlan0]']
+        """
+        interface_info = client.get_interface_info()
+        shortened_info = []
+
+        for interface in interface_info:
+            shortened_info.append('{0} [{1}]'.format(interface.network, interface.interface_name))
+
+        return shortened_info
 
     # Create the top title label
     title_label = tk.Label(text='PynPong Launcher', fg='white', bg='#000040', padx=1, pady=20)
     title_label.pack(side=tk.TOP, fill=tk.BOTH)
 
     # Create the list of games
+    global listbox
     listbox = tk.Listbox(main_window)
     listbox.pack(side=tk.LEFT, expand=True, fill=tk.BOTH)
     # Add scrollbar
@@ -49,7 +135,13 @@ def main():
     button_frame = tk.Frame(main_window)
     tk.Button(button_frame, text='Host a Game', height=3, width=30).pack()
     tk.Button(button_frame, text='Join Selected Game', height=3, width=30).pack()
-    tk.Button(button_frame, text='Refresh Game List', height=2, width=20, command=get_games).pack()
+    tk.Button(button_frame, text='Refresh Game List', height=2, width=20,
+              command=lambda: get_games(selected_network)).pack()
+    networks = get_addresses()
+    selected_network = tk.StringVar()
+    selected_network.set(networks[0])
+    interface_menu = tk.OptionMenu(button_frame, selected_network, *networks)
+    interface_menu.pack()
     button_frame.pack(side=tk.RIGHT)
 
     # Set it so that if the X is pressed the application quits

pynpong/networking/host.py

@@ -1,36 +1,25 @@
-import psutil
+import socket
 
+LOCAL_IP = '127.0.0.1'
+SERVER_PORT = 29987
+SERVER_BUFFER = 1024
 
-class InterfaceInfo:
-    """
-    Class used for storing interface information to make it easier to use
-    """
-    def __init__(self, interface_name, address, subnet_mask):
-        self.interface_name = interface_name
-        self.address = address
-        self.subnet_mask = subnet_mask
+udp_server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+udp_server_socket.bind((LOCAL_IP, SERVER_PORT))
 
-    def __str__(self):
-        return '(Interface:{0}, Address:{1}, Subnet Mask:{2})'.format(self.interface_name,
-                                                                      self.address, self.subnet_mask)
+waiting_for_connection = True
 
-    def __repr__(self):
-        return '(Interface:{0}, Address:{1}, Subnet Mask:{2})'.format(self.interface_name,
-                                                                      self.address, self.subnet_mask)
+while waiting_for_connection:
+    received = udp_server_socket.recvfrom(SERVER_BUFFER)
+    message = received[0]
+    address = received[1]
 
+    decoded_message = message.decode('UTF-8')
+    if decoded_message.split(';')[0] != 'PYPONGREQ':
+        message = 'PYPONGRST;ERROR:INVALID HEADER'
+        udp_server_socket.sendto(message.encode('UTF-8'), address)
+    else:
+        message = 'PYPONGRST;ECHO:{0}'.format(decoded_message)
+        udp_server_socket.sendto(message.encode('UTF-8'), address)
 
-def main():
-    raw_interface_data = psutil.net_if_addrs()
-    interface_data = []
-
-    # Extract needed information from psutil and put it into a InterfaceInfo object
-    for interface in raw_interface_data:
-        address = (raw_interface_data.get(interface)[0]).address
-        subnet_mask = (raw_interface_data.get(interface)[0]).netmask
-        interface_data.append(InterfaceInfo(interface, address, subnet_mask))
-
-    print(interface_data)
-
-
-if __name__ == '__main__':
-    main()
+udp_server_socket.close()

pynpong/networking/packet.py

@@ -0,0 +1,36 @@
+"""
+Contains the Packet class to help with the transmission, reading, and verification of infermation over the network
+"""
+
+
+class Packet:
+    """
+    Class that contains information to be sent over the network. Can self-verify and has methods (will have methods) to
+    easily encode and decode packet information
+    """
+    VALID_HEADERS = [
+        'PYPONGREQ',
+        'PYPONGRST'
+    ]
+    VALID_TYPES = [
+        'SVRINFO'
+    ]
+
+    def __init__(self, header, msg_type, *message):
+        self.header = header
+        self.msg_type = msg_type
+        self.message = []
+        for x in message:
+            self.message.append(x)
+
+    def integrity_check(self):
+        """
+        Verify that the information in the packet is correct and makes sense
+
+        :return: True if packet verifies correctly, False if not
+        """
+        if self.header not in Packet.VALID_HEADERS:
+            return False
+        if self.msg_type not in Packet.VALID_TYPES:
+            return False
+        return True