Receive packets in a dedicated thread, that is called "worm"

Signed-off-by: Yohann D'ANELLO <ynerant@crans.org>

squinnondation/squinnondation.py

@@ -5,6 +5,7 @@ import socket
 from argparse import ArgumentParser
 from enum import Enum
 from ipaddress import IPv6Address
+from threading import Thread
 from typing import Any, Optional, Tuple
 
 
@@ -58,20 +59,7 @@ class Squinnondation:
             pkt.body_length = pkt.body.length + 2
             squirrel.send_packet(hazelnut, pkt)
 
-        while True:
-            pkt, hazelnut = squirrel.receive_packet()
-            print(pkt.body.data.decode('UTF-8'))
-            pkt = Packet()
-            pkt.magic = 95
-            pkt.version = 0
-            pkt.body = DataTLV()
-            msg = f"Hello my dear hazelnut, I am {squirrel.nickname}!"
-            pkt.body.data = msg.encode("UTF-8")
-            pkt.body.sender_id = 42
-            pkt.body.nonce = 18
-            pkt.body.length = len(msg) + 1 + 1 + 8 + 4
-            pkt.body_length = pkt.body.length + 2
-            squirrel.send_packet(hazelnut, pkt)
+        Worm(squirrel).start()
 
 
 class TLV:
@@ -393,7 +381,7 @@ class Squirrel(Hazelnut):
     def receive_packet(self) -> Tuple[Packet, Hazelnut]:
         """
         Receive a packet from the socket and translate it into a Python object.
-        TODO: Translate the address into the correct hazelnut.
+        Warning: the process is blocking, it should be ran inside a dedicated thread.
         """
         data, addr = self.receive_raw_data()
         return Packet.unmarshal(data), self.find_hazelnut(addr[0], addr[1])
@@ -403,3 +391,34 @@ class Squirrel(Hazelnut):
         Receive a packet from the socket.
         """
         return self.socket.recvfrom(1024)
+
+
+class Worm(Thread):
+    """
+    The worm is the hazel listener.
+    It always waits for an incoming packet, then it  treats it, and continues to wait.
+    It is in a dedicated thread.
+    """
+    def __init__(self, squirrel: Squirrel, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.squirrel = squirrel
+
+    def run(self) -> None:
+        while True:
+            try:
+                pkt, hazelnut = self.squirrel.receive_packet()
+            except ValueError as error:
+                print("An error occured while receiving a packet: ", error)
+            else:
+                print(pkt.body.data.decode('UTF-8'))
+                pkt = Packet()
+                pkt.magic = 95
+                pkt.version = 0
+                pkt.body = DataTLV()
+                msg = f"Hello my dear hazelnut, I am {self.squirrel.nickname}!"
+                pkt.body.data = msg.encode("UTF-8")
+                pkt.body.sender_id = 42
+                pkt.body.nonce = 18
+                pkt.body.length = len(msg) + 1 + 1 + 8 + 4
+                pkt.body_length = pkt.body.length + 2
+                self.squirrel.send_packet(hazelnut, pkt)