Measure TTFB using python

ttfb.py

#!/usr/bin/env python3
from socket import gethostbyname, socket
from ssl import wrap_socket
from sys import argv
from time import time
from urllib.parse import urlparse


def main(url):
    pu = urlparse(url)
    port = pu.port or (80 if pu.scheme == 'http' else 443)

    t_start = time()
    host = gethostbyname(pu.hostname)
    t_dns = time()

    with socket() as _s:
        s = wrap_socket(_s) if pu.scheme == 'https' else _s

        s.connect((host, port))
        t_connect = time()
        s.send(('GET %s HTTP/1.1\r\n'
                'Host: %s\r\n'
                'User-Agent: Mozilla/5.0\r\n'
                '\r\n').encode())
        s.recv(1)
        t_tfb = time()
        print('TTFB', round((t_tfb - t_start) * 1000), 'ms')
        print('DNS', round((t_dns - t_start) * 1000), 'ms')
        print('CONN', round((t_connect - t_dns) * 1000), 'ms')


if __name__ == '__main__':
    main(argv[1])