LibrePortal/scripts/crontab/app/crontab_backup_scheduler.sh
librelad 4ce0340ef8 refactor(backup): replace per-app cron stagger with task-queue scheduler
Application backups were driven by one crontab entry per app, each offset by
id * CFG_BACKUP_CRONTAB_APP_INTERVAL minutes. That minute offset is written
straight into cron's 0-59 minute field, so past ~20 apps it overflowed into
an invalid entry that silently never fired, and the fixed spacing could not
serialize backups that ran longer than the gap.

Replace it with a single daily entry (`libreportal backup scheduled`) that
enqueues a backup task per enabled app. The existing systemd task processor
drains them serially — no minute overflow, real serialization, and backups
are now visible/cancellable in the Tasks UI. Per-app enable is read from
CFG_<APP>_BACKUP at schedule time instead of being mirrored into crontab.

Removes the stagger machinery (timing/setup/check/remove scripts), the
now-unused cron_jobs table + insert, and the CFG_BACKUP_CRONTAB_APP_INTERVAL
config knob and its WebUI field.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>
2026-05-22 14:34:35 +01:00

32 lines
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Bash

#!/bin/bash
# Install (or refresh) the single daily crontab entry that drives application
# backups. The entry runs `libreportal backup scheduled`, which enqueues a
# backup task per enabled app for the processor to drain serially.
crontabSetupBackupScheduler()
{
local ISCRON=$( (sudo -u $sudo_user_name crontab -l) 2>/dev/null )
if [[ "$ISCRON" == *"command not found"* ]]; then
isNotice "Crontab is not found. Unable to set up the backup scheduler."
return 0
fi
if ! sudo -u $sudo_user_name crontab -l 2>/dev/null | grep -q "cron is set up for $sudo_user_name"; then
isNotice "Crontab is not set up, skipping backup scheduler until it's found."
return 0
fi
local marker="# CRONTAB BACKUP SCHEDULER"
local scheduler_entry="$CFG_BACKUP_CRONTAB_APP libreportal backup scheduled $marker"
# Drop any previous scheduler entry, then re-add the current one so a
# changed schedule (CFG_BACKUP_CRONTAB_APP) always takes effect.
local result=$(sudo -u $sudo_user_name crontab -l 2>/dev/null | grep -v "$marker" | sudo -u $sudo_user_name crontab -)
local result=$( (sudo -u $sudo_user_name crontab -l 2>/dev/null; echo "$scheduler_entry") | sudo -u $sudo_user_name crontab - )
checkSuccess "Installing the daily backup scheduler entry"
local schedule_time=$(echo "$CFG_BACKUP_CRONTAB_APP" | cut -d' ' -f2)
isSuccessful "Enabled apps will be queued for backup daily at ${schedule_time}:00"
}