Add DEBUG_HELPER

[DL6ER]

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10

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Add DEBUG_HELPER option. This option logs any helper activity (and possible errors) to pihole-FTL.log to ease debugging.

Exemplary configuration:

$ cat /etc/dnsmasq.d/99-script.conf 
dhcp-script=/tmp/dhcp-script.sh

$ cat /tmp/dhcp-script.sh
#!/bin/bash
echo "$@" >> /tmp/dhcp-script.log

$ cat /tmp/dhcp-script.log
old 11:55:1f:a1:55:3c 192.168.0.212 ThinkPad-Ubuntu

Exemplary log content:

$ grep "Script:" /var/log/pihole-FTL.log
[2020-10-27 07:29:46.105 3592/F3585] Script: Starting helper for action "old"
[2020-10-27 07:29:46.106 3598/F3585] Script: Executing "/tmp/dhcp-script.sh" with arguments: "old 11:55:1f:a1:55:3c 192.168.0.212 ThinkPad-Ubuntu"

On errors, the reason will be logged:

[2020-10-27 07:31:19.844 3592/F3585] Script: Starting helper for action "old"
[2020-10-27 07:31:19.845 3674/F3585] Script: Executing "/tmp/dhcp-script.sh" with arguments: "old 11:55:1f:a1:55:3c 192.168.0.212 ThinkPad-Ubuntu"
[2020-10-27 07:31:19.846 3674/F3585] Script: FAILED to execute "/tmp/dhcp-script.sh": No such file or directory

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/pi-hole-core-web-v5-2-and-ftl-v5-3-released/40909/1