Replace catalogs for catalog as observed in a live core db data files

[agu3rra]

Description

While reading documentation at https://docs.influxdata.com/influxdb3/core/admin/backup-restore/, I decided to check the existing folder structure on the deployed instance of InfluxDB3 Core 3.7.0 that I have running on a Kubernetes cluster. I noticed the folder catalogs (with an s), does not exist, but one named catalog does. Hence I sent this PR in order to avoid people silently missing to copy that folder as part of the backup process.

I also noticed that the file _catalog_checkpoint was missing on my instance, but so far I will assume perhaps it will be created at a later point in time by the DB runtime.

Sample directory listing

The below terminal log was taken from the machine were I have InfluxDB running. It shows the existing directory structure from ls -lah commands, and it's possible to observe there's no catalogs directory (only catalog)

influxdb3@influxdb3-core-0:/$ pwd
/
influxdb3@influxdb3-core-0:/$ cd var
influxdb3@influxdb3-core-0:/var$ ls
backups  cache  lib  local  lock  log  mail  opt  run  spool  tmp
influxdb3@influxdb3-core-0:/var$ cd lib
influxdb3@influxdb3-core-0:/var/lib$ ls
apt  dpkg  influxdb3  misc  pam  shells.state  systemd
influxdb3@influxdb3-core-0:/var/lib$ cd influxdb3/
influxdb3@influxdb3-core-0:/var/lib/influxdb3$ ls
data  plugins
influxdb3@influxdb3-core-0:/var/lib/influxdb3$ cd plugins
influxdb3@influxdb3-core-0:/var/lib/influxdb3/plugins$ ls
lost+found
influxdb3@influxdb3-core-0:/var/lib/influxdb3/plugins$ ls -lah
total 28K
drwxrwsr-x 4 root      influxdb3 4.0K Dec 30 12:19 .
drwxr-xr-x 1 influxdb3 influxdb3 4.0K Dec 31 15:20 ..
drwxrwsr-x 5 influxdb3 influxdb3 4.0K Dec 30 12:19 .venv
drwxrws--- 2 root      influxdb3  16K Dec 30 12:19 lost+found
influxdb3@influxdb3-core-0:/var/lib/influxdb3/plugins$ cd ..
influxdb3@influxdb3-core-0:/var/lib/influxdb3$ cd data
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data$ ls -lah
total 28K
drwxrwsr-x 4 root      influxdb3 4.0K Dec 30 12:19 .
drwxr-xr-x 1 influxdb3 influxdb3 4.0K Dec 31 15:20 ..
drwxrws--- 2 root      influxdb3  16K Dec 30 12:18 lost+found
drwxrwsr-x 7 influxdb3 influxdb3 4.0K Dec 31 15:20 node0
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data$ cd node0
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0$ ls -lah
total 68K
drwxrwsr-x 7 influxdb3 influxdb3 4.0K Dec 31 15:20 .
drwxrwsr-x 4 root      influxdb3 4.0K Dec 30 12:19 ..
drwxrwsr-x 3 influxdb3 influxdb3 4.0K Dec 30 12:19 catalog
drwxrwsr-x 3 influxdb3 influxdb3 4.0K Dec 30 20:23 db-indices
drwxrwsr-x 3 influxdb3 influxdb3 4.0K Dec 30 18:37 dbs
drwxrwsr-x 2 influxdb3 influxdb3 4.0K Jan  4 13:44 snapshots
-rw-r--r-- 1 influxdb3 influxdb3   31 Dec 31 15:20 table-index-conversion-completed
drwxrwsr-x 2 influxdb3 influxdb3  40K Jan  4 13:45 wal
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0$ cat table-index-conversion-completed 
{
  "last_sequence_number": 1
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0$ cd catalog/
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0/catalog$ ls
v2
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0/catalog$ cd v2
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0/catalog/v2$ ls
logs  snapshot
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0/catalog/v2$ cd snapshot 
bash: cd: snapshot: Not a directory
influxdb3@influxdb3-core-0:/var/lib/influxdb3/data/node0/catalog/v2$ ls
logs  snapshot

Legal

• Signed the InfluxData CLA
  (if necessary)
• Rebased/mergeable