controller.py

import ipaddress
import os
import time
import socket
import logging

logging.basicConfig(level=logging.INFO)



# "10.12.X.0/29" in Pi lab
# 10.0.1.0/29 in homelab
#WORKER_IPS = ["10.12.4.1", "10.12.4.2","10.12.4.3","10.12.4.4","10.12.4.5","10.12.4.6"]

WORKER_IPS = ["10.0.1.2", "10.0.1.5", "10.0.1.6", "10.0.1.7"]

WORKER_PORT = 5000
BUFFER_SIZE = 1024

print(os.environ['WORKERS'])
#print("hello world")

#for ip in ipaddress.IPv4Network("10.0.1.0/29", False):
#    print(ip)
#    WORKER_IPS.append(str(ip))

def send_health_check():
    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as controller_socket:
        rtt_results = []

        for i, worker_ip in enumerate(WORKER_IPS):
            
            if i > (int(os.environ['WORKERS']) - 1):
                break 


            rtt_result = []
            for j in range(10):
                start_time = time.time()
                message = "Health check"
                controller_socket.sendto(message.encode(), (worker_ip, WORKER_PORT))
                logging.info(f"Sent health check to Worker {i + 1} at {worker_ip}:{WORKER_PORT}")
                try:
                    controller_socket.settimeout(10)
                    data, _ = controller_socket.recvfrom(BUFFER_SIZE)
                    end_time = time.time()
                    rtt = (end_time - start_time) * 1000  # RTT in milliseconds
                    rtt_result.append(rtt)
                    logging.info(f"Received response from Worker {i + 1} ({worker_ip}): {data.decode()}")
                    logging.info(f"RTT for Worker {i + 1}: {rtt:.2f} ms")     
                except socket.timeout:
                    logging.warning(f"Timeout: No response from Worker {i + 1} ({worker_ip})")
                    rtt_result.append(None)
            valid_rtts = [rtt for rtt in rtt_result if rtt is not None]

            if valid_rtts:
                avg_rtt = sum(valid_rtts) / len(valid_rtts)
                logging.info(f"Average RTT for worker {i + 1}: {avg_rtt:.2f} ms")
                rtt_results.append(avg_rtt)



        # Calculate and log the average RTT if there are valid results
        valid_rtts = [rtt for rtt in rtt_results if rtt is not None]
        if valid_rtts:
            avg_rtt = sum(valid_rtts) / len(valid_rtts)
            logging.info(f"Average total RTT: {avg_rtt:.2f} ms")
        else:
            logging.warning("No valid RTTs received")

if __name__ == "__main__":
    send_health_check()