14-least-connections-load-balancer.py

'''
Simulate a Least Connections algorithm for load balancing. Track the number of active connections to each server and assign new tasks to the server with the fewest. 
'''

import random
import time

class Server:
    def __init__(self, id):
        self.id = id
        self.connections = 0

    def add_connection(self):
        self.connections += 1

    def remove_connection(self):
        if self.connections > 0:
            self.connections -= 1

class LoadBalancer:
    def __init__(self, num_servers=2, max_connections=6):
        self.servers = [Server(i) for i in range(1, num_servers + 1)]
        self.total_connections = 0
        self.max_connections = max_connections

    def assign_task(self):
        if self.total_connections < self.max_connections:
            server = min(self.servers, key=lambda s: s.connections)
            server.add_connection()
            self.total_connections += 1
            print(f"New connection assigned to Server {server.id}\n")

    def release_task(self):
        if random.random() < 0.5 and self.total_connections > 0:
            server = random.choice(self.servers)
            if server.connections > 0:
                server.remove_connection()
                self.total_connections -= 1
                print(f"Connection closed on Server {server.id}\n")

    def display_server_loads(self):
        print("Current Connections:")
        for server in self.servers:
            print(f"Server {server.id}: {server.connections} connections")
        print("-" * 30, "\n")

    def run_simulation(self, duration=15):
        start_time = time.time()
        while time.time() - start_time < duration and self.total_connections < self.max_connections:
            self.assign_task()
            time.sleep(0.5)
            self.release_task()
            time.sleep(0.5)
            self.display_server_loads()
            time.sleep(1)

        print("\nFinal Connections:")
        for server in self.servers:
            print(f"Server {server.id}: {server.connections} connections")
        print("-" * 30)

if __name__ == "__main__":
    lb = LoadBalancer()
    lb.run_simulation(duration=15)