Add script to switch simcom modem to public ip address at boot

And recheck it every hour with the timer unit

tools/switch_to_public_ip.py

@@ -0,0 +1,62 @@
+#! /usr/bin/env python3
+
+import os
+import sys
+import nmcli
+if os.getenv("SUDO_USER") is not None:
+    homedir = os.path.join("/home", os.getenv("SUDO_USER"))
+else:
+    homedir = os.path.expanduser('~')
+
+sys.path.insert(1, os.path.join(homedir, "sim-modem"))
+from src.sim_modem import *
+
+nmcli.disable_use_sudo()
+CONN_NAME='Cellular Modem'
+
+def sleep(timeout, retry=50):
+    def the_real_decorator(function):
+        def wrapper(*args, **kwargs):
+            retries = 0
+            while retries < retry:
+                try:
+                    value = function(*args, **kwargs)
+                    if value is not None:
+                        return value
+                except:
+                    print(f'Sleeping for {timeout + retries*timeout} seconds')
+                    time.sleep(timeout + retries*timeout)
+                    retries += 1
+
+        return wrapper
+    return the_real_decorator
+
+@sleep(10)
+def check_modem():
+    nmcli.connection.show(CONN_NAME)
+    if nmcli.connection.show(CONN_NAME).get("GENERAL.STATE") == 'activated':
+        return True
+
+@sleep(10)
+def get_public_ip_address():
+    return modem.get_ip_address()
+
+@sleep(10)
+def get_in_use_ip_address():
+    return nmcli.connection.show(CONN_NAME)['IP4.ADDRESS[1]'].split('/')[0]
+
+check_modem()
+modem = Modem('/dev/ttymodemAT')
+ip_in_use = get_in_use_ip_address()
+public_ip = get_public_ip_address()
+
+print("Ip address in use: ", ip_in_use)
+print("Public Ip address: ", public_ip)
+
+if ip_in_use != public_ip:
+    modem.set_usbnetip_mode(1)
+    print("Request to switch to public IP address done!")
+    print("It could take a few minutes to be active")
+else:
+    print("We are already using the public Ip")
+

unit/modem_public_ip.service

@@ -0,0 +1,14 @@
+[Unit]
+Description=Switch Simcom modem to public ip address
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=forking
+User={user}
+ExecStart={python_path} {script_path}/tools/switch_to_public_ip.py
+Restart=on-failure
+RestartSec=30
+
+[Install]
+WantedBy=multi-user.target

unit/modem_public_ip.timer

@@ -0,0 +1,9 @@
+[Unit]
+Description=Run modem_public_ip.service every hour
+
+[Timer]
+OnCalendar=*-*-* *:00:00
+Persistent=true
+
+[Install]
+WantedBy=timers.target