rpitx pocsag - simple and dirty udp forwarder

lib_systemd_system_pocsag-udp-relay.service

[Unit]
Description=POCSAG UDP Relay
After=network-online.target
Wants=network-online.target systemd-networkd-wait-online.service
 
[Service]
Type=simple
ExecStart=/usr/bin/python3 /usr/local/bin/pocsag-udp-relay.py
StandardInput=tty-force
Restart=on-failure
RestartSec=5s
 
[Install]
WantedBy=multi-user.target

sudoers.txt

#
# This file MUST be edited with the 'visudo' command as root.
#
# Please consider adding local content in /etc/sudoers.d/ instead of
# directly modifying this file.
#
# See the man page for details on how to write a sudoers file.
#
Defaults        env_reset
Defaults        mail_badpass
Defaults        secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

# Host alias specification

# User alias specification

# Cmnd alias specification

# User privilege specification
root    ALL=(ALL:ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

# Allow anybody to use the pocsag transmitter
ALL     ALL=(root) NOPASSWD: /usr/local/sbin/pocsag

# See sudoers(5) for more information on "#include" directives:

#includedir /etc/sudoers.d

usr_local_bin_pocsag-udp-relay.py

#!/usr/bin/env python3
import socket
import subprocess

UDP_PORT = 42069
RIC = b"1123079"
# ^ ^ ^ Here we are hardcoding the RIC. You can amend that and line 18
# if you want to blindly trust the sender to pass RIC and colon character instead.

sock = socket.socket(socket.AF_INET, # Internet
                     socket.SOCK_DGRAM) # UDP
sock.bind(('', UDP_PORT))

while True:
    data, addr = sock.recvfrom(1024) # buffer size is 1024 bytes
    print("received message: %s" % data)
    msg = data[:80]
    page = RIC + b":"+ msg
    result = subprocess.run(['sudo', 'pocsag', '-f',  '153225000'], input=page, capture_output=True)
    print('stdout:', result.stdout)
    print('stderr:', result.stderr)