Traceroute Reference

import subprocess
import platform
import re

def traceroute(host: str, max_hops: int = 30) -> list[dict]:
    """Run traceroute and parse output."""
    system = platform.system()
    if system == "Windows":
        cmd = ["tracert", "-h", str(max_hops), host]
    else:
        cmd = ["traceroute", "-m", str(max_hops), host]

    result = subprocess.run(cmd, capture_output=True, text=True, timeout=60)
    lines = result.stdout.splitlines()
    hops = []
    for line in lines[1:]:  # skip header
        # Parse hop number and RTT values
        match = re.match(r"\s*(\d+)\s+(.+)", line)
        if match:
            hop_num = int(match.group(1))
            rest = match.group(2)
            times = re.findall(r"([\d.]+)\s*ms", rest)
            hostname = re.search(r"([\w.-]+)\s+\(", rest)
            hops.append({
                "hop": hop_num,
                "host": hostname.group(1) if hostname else "*",
                "times_ms": [float(t) for t in times],
            })
    return hops

hops = traceroute("google.com", max_hops=15)
for hop in hops:
    avg = sum(hop["times_ms"]) / len(hop["times_ms"]) if hop["times_ms"] else None
    avg_str = f"{avg:.1f} ms" if avg else "*"
    print(f"{hop['hop']:2d}  {hop['host']:<40} {avg_str}")