Add human-readable table output mode

[DL6ER]

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How familiar are you with the codebase?:

10

---

A small Christmas present 🎄: pihole-FTL sqlite3 -h ...

Normal table printing:

$ pihole-FTL sqlite3 /etc/pihole/pihole-FTL.db "SELECT * FROM network_addresses LIMIT 2"
19|169.254.48.28|1610737320||
20|169.254.157.55|1610737320||

New human-readable output (added -h):

$ pihole-FTL sqlite3 -h /etc/pihole/pihole-FTL.db "SELECT * FROM network_addresses LIMIT 2"
network_id  ip              lastSeen    name    nameUpdated
----------  --------------  ----------  ------  -----------
19          169.254.48.28   1610737320  (null)  (null)     
20          169.254.157.55  1610737320  (null)  (null)

This also works in interactive mode:

$ pihole-FTL sqlite3 -h /etc/pihole/pihole-FTL.db

Pi-hole FTL v5.11-51-g3511341f-dirty
SQLite version 3.37.0 2021-11-27 14:13:22
Enter ".help" for usage hints.

sqlite> SELECT * FROM network_addresses LIMIT 2;
network_id  ip              lastSeen    name    nameUpdated
----------  --------------  ----------  ------  -----------
19          169.254.48.28   1610737320  (null)  (null)     
20          169.254.157.55  1610737320  (null)  (null)

sqlite>

and even without specifying any database at all:

$ pihole-FTL sqlite3 -h

Pi-hole FTL v5.11-51-g3511341f-dirty
SQLite version 3.37.0 2021-11-27 14:13:22
Enter ".help" for usage hints.

sqlite> CREATE TABLE a (first,second);

sqlite> INSERT INTO a VALUES (1,2);

sqlite> SELECT * FROM a;
first  second
-----  ------
1      2

sqlite>

It works by calling the SQLite3 shell with the options -column -header -nullvalue (null) automatically enabled without the user having to enter them manually.

[yubiuser]

Nice gift. You may want to add -h to the help text as well so it can be found. Its Christmas, not Eastern... 😉

[yubiuser]

Santa Claus is coming to town...

[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-ftl-v5-13-web-v5-10-and-core-v5-8-released/52254/1