Add a weekly dump of the Weather database

weather-dump.timer runs weather-dump weekly, keeping the two newest ISO weeks in
~/.local/share/ens-forecast/dumps, which simple_backup then copies; the login comes
from ~/.config/ens-forecast/dump.cnf (not tracked).

.config/systemd/user/weather-dump.service

@@ -0,0 +1,11 @@
+[Unit]
+Description=Dump the Weather database to ~/.local/share/ens-forecast/dumps
+StartLimitIntervalSec=2h
+StartLimitBurst=4
+
+[Service]
+Type=oneshot
+ExecStart=%h/.local/bin/weather-dump
+# MariaDB not up yet (e.g. caught up right after boot)? retry a few times
+Restart=on-failure
+RestartSec=5min

.config/systemd/user/weather-dump.timer

@@ -0,0 +1,9 @@
+[Unit]
+Description=Dump the Weather database weekly
+
+[Timer]
+OnCalendar=weekly
+Persistent=true
+
+[Install]
+WantedBy=timers.target

.github/README.md

@@ -17,7 +17,7 @@ install script. This README lives in `.github/` to keep it out of the home direc
 | Audio / media | mpd, ncmpcpp, mpDris2, mpv, beets, pipewire |
 | Packaging | `.config/aurutils-makepkg.conf`, `.config/aurb/`, `.local/bin/aurb` / `aurs` (aurutils wrappers) |
 | Services | `.config/systemd/user/` (timers and overrides) |
-| Scripts | `.local/bin/` (screen layout, phone mount, video helpers, Library and Garmin database dumps) |
+| Scripts | `.local/bin/` (screen layout, phone mount, video helpers, Library, Garmin and Weather database dumps) |
 
 Note: `config.fish` sources `~/.bash_aliases`, so the aliases apply in both shells.
 

.local/bin/weather-dump

@@ -0,0 +1,24 @@
+#!/bin/bash
+# Dump the Weather database (ens-forecast) to a per-ISO-week file, keeping the two newest weeks.
+set -euo pipefail
+
+cnf=${XDG_CONFIG_HOME:-$HOME/.config}/ens-forecast/dump.cnf
+dir=${XDG_DATA_HOME:-$HOME/.local/share}/ens-forecast/dumps
+out=$dir/Weather-$(date +%G-W%V).sql.gz
+keep=2
+
+umask 077
+mkdir -p "$dir"
+
+# Write to a temporary file so a failed dump never replaces a good one
+tmp=$(mktemp "$dir/.dump.XXXXXX")
+trap 'rm -f "$tmp"' EXIT
+
+mariadb-dump --defaults-extra-file="$cnf" --single-transaction --databases Weather | gzip > "$tmp"
+mv "$tmp" "$out"
+
+# Names sort by week, so all but the last $keep are the old ones
+dumps=("$dir"/Weather-*.sql.gz)
+if (( ${#dumps[@]} > keep )); then
+    rm -f -- "${dumps[@]:0:${#dumps[@]}-keep}"
+fi