From 03bf6bae0afd7fe8495b576f80991e9601eae50d Mon Sep 17 00:00:00 2001
From: Katharina <katharina.willig@outlook.com>
Date: Sat, 23 Nov 2024 16:41:20 +0100
Subject: [PATCH] election
---
__pycache__/kserver.cpython-313.pyc | Bin 3481 -> 3481 bytes
kserver.py | 94 ++++++++++++++--------------
2 files changed, 47 insertions(+), 47 deletions(-)
diff --git a/__pycache__/kserver.cpython-313.pyc b/__pycache__/kserver.cpython-313.pyc
index 401d92341d7bb4d3c2994fd3d5d394df9ea34069..962c797ea7dc3b5fbdc84680922bf3b07d049d8e 100644
GIT binary patch
delta 19
acmbO!JyV+NGcPX}0|NuYvCA8|`gs90kOg`G
delta 19
acmbO!JyV+NGcPX}0|NuYhl?Az`gs91f(4=g
diff --git a/kserver.py b/kserver.py
index 453d229..eaecd0a 100644
--- a/kserver.py
+++ b/kserver.py
@@ -5,13 +5,10 @@ import uuid
broadcast_ip = '255.255.255.255'
broadcast_port = 55555
-# create unique server-ID
+# Create a unique server ID
server_id = str(uuid.uuid4())
-# Set to store UUIDs of other servers
-server_uuids = set()
-
-# create server-socket for broadcast
+# Create server socket for broadcasting
server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
@@ -19,71 +16,74 @@ server_socket.bind(('', broadcast_port))
print(f"Server is running with ID {server_id} and broadcasting on port {broadcast_port}...")
-#broadcast function
+# Store the current leader's ID
+current_leader = None
+
+# Broadcast function
def broadcast(message):
- """sends messages to all server-IDs in the network"""
+ """Send messages to all other nodes in the network."""
full_message = f"[{server_id}] {message}".encode()
server_socket.sendto(full_message, (broadcast_ip, broadcast_port))
-#listener function
+# Listener function
def listen():
- """receives messages from clients and broadcast them."""
+ """Receive messages and implement LCR logic."""
+ global current_leader
+
while True:
try:
message, client_address = server_socket.recvfrom(4096)
decoded_message = message.decode()
- # Extract UUID from the message
+ # Extract sender UUID and payload
if decoded_message.startswith("[") and "]" in decoded_message:
sender_uuid = decoded_message.split("]")[0][1:]
-
+ payload = decoded_message.split("]")[1].strip()
+
# Ignore messages from self
if sender_uuid == server_id:
continue
+
+ # LCR logic
+ if payload == "START_ELECTION":
+ print(f"Received election start from {sender_uuid}")
+ if sender_uuid > server_id:
+ # Forward the sender's ID
+ broadcast(f"START_ELECTION {sender_uuid}")
+ elif sender_uuid < server_id:
+ # Send own ID into the ring
+ broadcast(f"START_ELECTION {server_id}")
+ else:
+ # If sender_uuid == server_id, we are the leader
+ current_leader = server_id
+ broadcast(f"LEADER {server_id}")
+ print(f"I am the leader: {server_id}")
- # Add the UUID to the set if it's not already known
- if sender_uuid not in server_uuids:
- server_uuids.add(sender_uuid)
- print(f"Discovered new server UUID: {sender_uuid} and server set: {server_uuids}")
- # print(server_uuids)
-
- #checks if the message containts the string "entered"
- if decoded_message.__contains__("entered"):
- print(f"{client_address} entered the chat.")
-
- print(f"Received from {client_address}: {decoded_message}")
-
- broadcast(decoded_message)
-
- #exceptions
+ elif payload.startswith("LEADER"):
+ leader_id = payload.split(" ")[1]
+ current_leader = leader_id
+ print(f"Leader has been elected: {leader_id}")
+
except socket.error as e:
print(f"An error occurred: {e}")
break
- #does not work
except KeyboardInterrupt:
- print("\nServer wird beendet...")
+ print("\nShutting down server...")
break
+# Start the election
+def start_election():
+ """Initiate the LCR election process."""
+ print("Starting election...")
+ broadcast(f"START_ELECTION {server_id}")
+
if __name__ == "__main__":
- #main thread
- listen_thread= threading.Thread(target=listen)
- #listen_thread.daemon = True
+ # Start the listener thread
+ listen_thread = threading.Thread(target=listen)
listen_thread.start()
- #print(listen_thread.is_alive())
- #listen()
-
- # Example of broadcasting your UUID periodically (optional)
- def periodic_broadcast():
- import time
- while True:
- try:
- broadcast("Server is running")
- time.sleep(10) # Broadcast every 5 seconds
- except KeyboardInterrupt:
- break
-
- broadcast_thread = threading.Thread(target=periodic_broadcast)
- broadcast_thread.daemon = True # Stop when main thread stops
- broadcast_thread.start()
+ # Start election after a short delay
+ import time
+ time.sleep(2)
+ start_election()
--
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