Query ZeroTier is a script that accesses the ZeroTier API to determine network peers of a given network, then updates /etc/hosts to allow for human-like name access.

query-zt-update-hosts.py

"""Query ZeroTier is a script that accesses the ZeroTier API to determine network peers
of a given network, then updates /etc/hosts to allow for human-like name access.

(c) Copyright 2020 John Muchovej
"""
#!/usr/bin/env python

import os
import sys
import json

import requests
from jinja2 import Template
from word2number import w2n

assert sys.version_info.major == 3 and sys.version_info.minor >= 6, \
    "Please use Python 3.6+ to run this script."

def get(postfix: str, token: str):
    ZT = "https://my.zerotier.com/api"
    headers = {
        "Authorization": f"bearer {token}",
    }
    try:
        response = requests.get(f"{ZT}/{postfix}", headers=headers)
        response.raise_for_status()
    except requests.execptions.HTTPError as e:
        raise SystemExit(e)

    return json.loads(response.content.decode("utf-8"))


def get_network(name: str):
    networks = get("network")

    for network in networks:
        if network["config"]["name"] == name:
            return network

    raise ValueError(f"Could not find `{name}` in available networks.")


def get_clients(network: dict):
    zt_id = network["config"]["id"]

    members = get(f"network/{zt_id}/member")

    host = Template("{{ ip }}    {{ name }}")
    hosts = []
    for member in members:
        name = member["name"]
        for ip in member["config"]["ipAssignments"]:
            ip = f"{ip:15s}"
            hosts.append(host.render(ip=ip, name=abbr(name)))

    return hosts


def write(ZTHosts: list):
    header = "# ZeroTier Clients"
    footer = "# /ZeroTier Clients"
    ZTHosts = [header] + ZTHosts + [footer]

    hosts = open("/etc/hosts", "r").read().split("\n")

    try:
        start = hosts.index(header)
    except ValueError:
        start = len(hosts)

    try:
        end = hosts.index(footer)
    except ValueError:
        hosts.extend([""] * len(ZTHosts))

    for line, host in enumerate(ZTHosts, start):
        hosts[line] = host

    return "\n".join(hosts)


def abbr(hostname: str):
    split = hostname.split("-")
    alias = ""

    for s in split:
        try:
            alias += str(w2n.word_to_num(s))
        except ValueError:
            alias += s[0]

    return f"{hostname} {alias}"


if __name__ == "__main__":
    from argparse import ArgumentParser
    parser = ArgumentParser("query-zerotier-update-hosts")
    parser.add_argument("network", type=str)
    parser.add_argument("token", type=str, required=False)

    args = parser.parse_args()

    if args.token:
        token = args.token
    else:
        token = os.environ["ZT_TOKEN"]

    targets = get_network(args.network)
    clients = get_clients(targets)
    new_etc = write(clients)

    # write ZeroTier hosts to /etc/hosts, requires `sudo`
    open("/etc/hosts", "w").write(new_etc)

requirements.txt

# Using requirements.txt strictly for those who fancy `pip`. Would recommend using Anaconda.
python >= 3.6
requests
word2number >= 1.1
Jinja2 >= 2.11