GPGME error in Arch (failed to synchronize all databases)

It had been a couple months since updating Arch (bad, I know, but it's headless and I forgot!)

When I went to run an update I saw this error happen...

sudo pacman -Syu
:: Synchronizing package databases...
 core                                                                      998.0   B  1399   B/s 00:01 [#############################################################] 100%
 extra                                                                     998.0   B  37.5 KiB/s 00:00 [#############################################################] 100%
 community                                                                 998.0   B  37.5 KiB/s 00:00 [#############################################################] 100%
error: GPGME error: No data
error: GPGME error: No data
error: GPGME error: No data
error: failed to synchronize all databases (invalid or corrupted database (PGP signature))
sudo pacman -Syu

So I inspected the database - and it was an HTML page!

less /var/lib/pacman/sync/core.db

The .db file clearly should not be a webpage - it turns out the mirror url was stale. So I  moved the entire sync directory...

sudo mv /var/lib/pacman/sync /var/lib/pacman/sync.BROKEN

And updated the mirror I was using by commenting out the broken one

> sudo nano /etc/pacman.d/mirrorlist

# I commented out the first 
# Server = https://archlinux.qern-industries.pw/$repo/os/$arch
Server = https://america.mirror.pkgbuild.com/$repo/os/$arch
Server = https://mirror.hackingand.coffee/arch/$repo/os/$arch
sudo nano /etc/pacman.d/mirrorlist

Ran the update again - but more things were also stale >.<

(61/61) checking package integrity                                                                     [#############################################################] 100%
error: openssl: signature from "Pierre Schmitz <pierre@archlinux.org>" is marginal trust
:: File /var/cache/pacman/pkg/openssl-3.0.7-4-x86_64.pkg.tar.zst is corrupted (invalid or corrupted package (PGP signature)).
Do you want to delete it? [Y/n] y
error: failed to commit transaction (invalid or corrupted package)
Errors occurred, no packages were upgraded.
sudo pacman -Syu

# Fix keys
sudo pacman-key --init
sudo pacman-key --populate archlinux

# Update keyring
sudo pacman -Sy archlinux-keyring

# Update system
sudo pacman -Syu
Update keyring and update system

(Solution for keyring found https://wiki.archlinux.org/title/Pacman/Package_signing#Upgrade_system_regularly)