Add a network monitoring for wifi connections

src/modules/octopi/filesystem/boot/octopi.txt

@@ -76,6 +76,16 @@
 #camera_http_webroot="./www-octopi"
 #camera_http_options="-n"
 
+# Configuration of network monitoring
+#
+# This enables network monitoring for wifi connections with a simple ping test.
+# If connection terminates by variable reasons system tries to restart the wifi connection to reestablish a connection.
+# The connection test is done every minute.
+# By default it is disabled (0 = off / 1 = on)
+# dstination_host can be an ip address or a hostname (for hostname ensure dns resosultion is working correctly)
+enable_network_monitor=0
+destination_host=192.168.1.1
+
 ### EXPERIMENTAL
 # Support for different streamer types.
 #

src/modules/octopi/filesystem/root/etc/systemd/system/networkcheck.service

@@ -0,0 +1,8 @@
+[Unit]
+ Description=Network Monitor
+ ConditionPathExists=/usr/local/bin/networkcheck
+
+[Service]
+ User=root
+ Type=simple
+ ExecStart=/usr/local/bin/networkcheck &

src/modules/octopi/filesystem/root/etc/systemd/system/networkcheck.timer

@@ -0,0 +1,10 @@
+[Unit]
+ Description=Network Monitor Trigger (every 1 minutes)
+ After=network.target
+
+[Timer]
+ OnCalendar=*-*-* *:*:00
+ AccuracySec=1s
+
+[Install]
+ WantedBy=timers.target

src/modules/octopi/filesystem/root/usr/local/bin/networkcheck

@@ -0,0 +1,28 @@
+#!/bin/bash
+
+source /boot/octopi.txt
+
+if [ $enable_network_monitor == 1 ] && [ "$destination_host" != "" ]; then
+
+    if [ -f /boot/octopi-wpa-supplicant.txt ]; then # check if config file exists
+	input="/boot/octopi-wpa-supplicant.txt"
+	while IFS= read -r line; do # read config file line by line
+	    if [[ $line =~ ^network=.* ]]; then # check if we have a network config if a line starts with "network="
+		echo "network config found..."
+		ping -c4 $destination_host > /dev/null # check if destination is reachable - possible by default the router
+		if [ $? != 0 ]; then
+		    echo "Destination not reachable - reconfigure interface..."
+		    sudo wpa_cli -i wlan0 reconfigure # reconfigure network to trigger reconnect
+		    sudo dhclient -v # ensure connection will be established by refresh dhcp lease
+		    echo "Reconnect done."
+		    exit 0 # if we detect multiple network configs exit after 1st one - one reconnect is enough :-)
+		else
+		    echo "Destination reachable - no action needed."
+		    exit 0 # destination reached - exit loop
+		fi
+	    fi
+	done < "$input"
+    fi
+else
+    echo "Network monitoring not enabled."
+fi

src/modules/octopi/start_chroot_script

@@ -258,6 +258,10 @@ fi
 
 systemctl_if_exists enable ffmpeg_hls.service
 
+### Network monitoring
+
+systemctl_if_exists enable networkcheck.timer
+
 #cleanup
 apt-get clean
 apt-get autoremove -y