Initial commit

dynamic-leases.py

@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+import argparse
+import csv
+import json
+import sys
+import requests
+from datetime import datetime
+from pathlib import Path
+
+api_url = "https://pi.hole/api"
+verify = "/etc/pihole/tls_ca.crt"
+default_password_file = "/etc/pihole/api_password"
+
+parser = argparse.ArgumentParser(description="List non-static (dynamic) Pi-hole DHCP leases.")
+parser.add_argument("-p", "--password-file", default=default_password_file,
+                     help=f"Path to file containing the Pi-hole API password (default: {default_password_file})")
+parser.add_argument("-t", "--table", action="store_true",
+                     help="Print a human-readable aligned table (with local time expiry)")
+parser.add_argument("-j", "--json", action="store_true",
+                     help="Print machine-readable output as JSON instead of the default CSV")
+args = parser.parse_args()
+
+if args.table and args.json:
+	parser.error("--table and --json are mutually exclusive")
+
+
+def read_password(path):
+	try:
+		return Path(path).read_text().strip()
+	except OSError as e:
+		raise SystemExit(f"Could not read password file '{path}': {e}")
+
+
+def format_expiry_human(value):
+	try:
+		return datetime.fromtimestamp(int(value)).strftime("%Y-%m-%d %H:%M:%S")
+	except (TypeError, ValueError):
+		return str(value)
+
+
+auth_payload = {"password": read_password(args.password_file)}
+
+with requests.post(f"{api_url}/auth", json=auth_payload, verify=verify) as auth:
+	auth_json = auth.json()
+	session = auth_json.get('session')
+	if not session or not session.get('sid'):
+		raise SystemExit(f"Authentication failed: {auth_json}")
+
+	headers = {
+		"X-FTL-SID": session.get('sid'),
+		"X-FTL-CSRF": session.get('sid')
+	}
+
+	try:
+		# Get static DHCP host mappings to know which MACs are static
+		with requests.get(f"{api_url}/config", headers=headers, verify=verify) as config:
+			config_json = config.json()
+			static_macs = set()
+			for entry in config_json.get('config').get('dhcp').get('hosts'):
+				mac = entry.split(",")[0].lower()
+				static_macs.add(mac)
+
+		# Get current active DHCP leases
+		with requests.get(f"{api_url}/dhcp/leases", headers=headers, verify=verify) as leases_resp:
+			leases_json = leases_resp.json()
+			leases = leases_json.get('leases', [])
+
+			non_static = [l for l in leases if l.get('hwaddr', '').lower() not in static_macs]
+
+			records = []
+			for lease in non_static:
+				records.append({
+					"ip": lease.get('ip', '-'),
+					"mac": lease.get('hwaddr', '-'),
+					"hostname": lease.get('name') or '-',
+					"expires": lease.get('expires', '-'),
+				})
+
+			if args.table:
+				if not records:
+					print("No non-static (dynamic) leases found.")
+				else:
+					rows = [(r["ip"], r["mac"], r["hostname"], format_expiry_human(r["expires"])) for r in records]
+					ip_w = max(len(r[0]) for r in rows + [("IP", "", "", "")])
+					mac_w = max(len(r[1]) for r in rows + [("", "MAC", "", "")])
+					name_w = max(len(r[2]) for r in rows + [("", "", "Hostname", "")])
+
+					print(f"{'IP':<{ip_w}}  {'MAC':<{mac_w}}  {'Hostname':<{name_w}}  Expires (local time)")
+					print(f"{'-' * ip_w}  {'-' * mac_w}  {'-' * name_w}  {'-' * 19}")
+					for ip, mac, name, expires in rows:
+						print(f"{ip:<{ip_w}}  {mac:<{mac_w}}  {name:<{name_w}}  {expires}")
+
+			elif args.json:
+				print(json.dumps(records, indent=2))
+
+			else:
+				# Default: machine-readable CSV, raw (unix timestamp) expiry
+				writer = csv.DictWriter(sys.stdout, fieldnames=["ip", "mac", "hostname", "expires"])
+				writer.writeheader()
+				writer.writerows(records)
+	finally:
+		requests.delete(f"{api_url}/auth", headers=headers, verify=verify)
+