frappy/bin/frappy-scan
Markus Zolliker bf9c946b1d frappy-scan: resolve ip numbers to names
Change-Id: I07bf7c274aeb52f2aaa58e8aa2f3bcb2788556ee
2025-03-17 09:36:50 +01:00

140 lines
4.4 KiB
Python
Executable File

#!/usr/bin/env python3
# *****************************************************************************
#
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Module authors:
# Alexander Zaft <a.zaft@fz-juelich.de>
#
# *****************************************************************************
"""SEC node autodiscovery tool."""
import argparse
import json
import os
import select
import socket
import sys
from collections import namedtuple
from time import time as currenttime
UDP_PORT = 10767
Answer = namedtuple('Answer',
'address, port, equipment_id, firmware, description')
def decode(msg, addr):
msg = msg.decode('utf-8')
try:
data = json.loads(msg)
except Exception:
return None
if not isinstance(data, dict):
return None
if data.get('SECoP') != 'node':
return None
try:
eq_id = data['equipment_id']
fw = data['firmware']
desc = data['description']
port = data['port']
except KeyError:
return None
addr, _scanport = addr
return Answer(addr, port, eq_id, fw, desc)
def print_answer(answer, *, short=False):
try:
hostname = socket.gethostbyaddr(answer.address)[0]
address = hostname
numeric = f' ({answer.address})'
except Exception:
address = answer.address
numeric = ''
if short:
# NOTE: keep this easily parseable!
print(f'{answer.equipment_id} {address}:{answer.port}')
return
print(f'Found {answer.equipment_id} at {address}{numeric}:')
print(f' Port: {answer.port}')
print(f' Firmware: {answer.firmware}')
desc = answer.description.replace('\n', '\n ')
print(f' Node description: {desc}')
print('-' * 80)
def scan(max_wait=1.0):
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
# send a general broadcast
try:
s.sendto(json.dumps(dict(SECoP='discover')).encode('utf-8'),
('255.255.255.255', UDP_PORT))
except OSError as e:
print('could not send the broadcast:', e)
# we still keep listening for self-announcements
start = currenttime()
seen = set()
while currenttime() < start + max_wait:
res = select.select([s], [], [], 0.1)
if res[0]:
try:
msg, addr = s.recvfrom(1024)
except socket.error: # pragma: no cover
continue
answer = decode(msg, addr)
if answer is None:
continue
if (answer.address, answer.equipment_id, answer.port) in seen:
continue
seen.add((answer.address, answer.equipment_id, answer.port))
yield answer
def listen(*, short=False):
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
if os.name == 'nt':
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
else:
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
s.bind(('0.0.0.0', UDP_PORT))
while True:
try:
msg, addr = s.recvfrom(1024)
except KeyboardInterrupt:
break
answer = decode(msg, addr)
if answer:
print_answer(answer, short=short)
if __name__ == '__main__':
parser = argparse.ArgumentParser()
parser.add_argument('-l', '--listen', action='store_true',
help='Keep listening after the broadcast.')
parser.add_argument('-s', '--short', action='store_true',
help='Print short info (always on when listen).')
args = parser.parse_args(sys.argv[1:])
short = args.listen or args.short
if not short:
print('-' * 80)
for answer in scan():
print_answer(answer, short=short)
if args.listen:
listen(short=short)