#!/usr/bin/env bash set -e BACKUP_PATH="/backup" # Make sure that required directories exist mkdir -p "${BACKUP_PATH}" mkdir -p "/etc/crontabs" chown git:git /backup chmod 2770 /backup # [string] BACKUP_INTERVAL Period expression # [string] BACKUP_RETENTION Period expression if [ -z "${BACKUP_INTERVAL}" ]; then echo "Backup disabled: BACKUP_INTERVAL has not been found" 1>&2 exit 1 fi if [ -z "${BACKUP_RETENTION}" ]; then echo "Backup retention period is not defined, default to 7 days" 1>&2 BACKUP_RETENTION='7d' fi # Parse BACKUP_INTERVAL environment variable and generate appropriate cron expression. Backup cron task will be run as scheduled. # Expected format: nu (n - number, u - unit) (eg. 3d means 3 days) # Supported units: h - hours, d - days, M - months parse_generate_cron_expression() { CRON_EXPR_MINUTES="*" CRON_EXPR_HOURS="*" CRON_EXPR_DAYS="*" CRON_EXPR_MONTHS="*" TIME_INTERVAL=$(echo "${BACKUP_INTERVAL}" | sed -e 's/[hdM]$//') TIME_UNIT=$(echo "${BACKUP_INTERVAL}" | sed -e 's/^[0-9]\+//') if [ "${TIME_UNIT}" = "h" ]; then if [ ! "${TIME_INTERVAL}" -le 23 ]; then echo "Parse error: Time unit 'h' (hour) cannot be greater than 23" 1>&2 exit 1 fi CRON_EXPR_MINUTES=0 CRON_EXPR_HOURS="*/${TIME_INTERVAL}" elif [ "${TIME_UNIT}" = "d" ]; then if [ ! "${TIME_INTERVAL}" -le 30 ]; then echo "Parse error: Time unit 'd' (day) cannot be greater than 30" 1>&2 exit 1 fi CRON_EXPR_MINUTES=0 CRON_EXPR_HOURS=0 CRON_EXPR_DAYS="*/${TIME_INTERVAL}" elif [ "${TIME_UNIT}" = "M" ]; then if [ ! "${TIME_INTERVAL}" -le 12 ]; then echo "Parse error: Time unit 'M' (month) cannot be greater than 12" 1>&2 exit 1 fi CRON_EXPR_MINUTES=0 CRON_EXPR_HOURS=0 CRON_EXPR_DAYS="1" CRON_EXPR_MONTHS="*/${TIME_INTERVAL}" else echo "Parse error: BACKUP_INTERVAL expression is invalid" 1>&2 exit 1 fi echo "${CRON_EXPR_MINUTES} ${CRON_EXPR_HOURS} ${CRON_EXPR_DAYS} ${CRON_EXPR_MONTHS} *" } # Parse BACKUP_RETENTION environment variable and generate appropriate find command expression. # Expected format: nu (n - number, u - unit) (eg. 3d means 3 days) # Supported units: m - minutes, d - days parse_generate_retention_expression() { FIND_TIME_EXPR='mtime' TIME_INTERVAL=$(echo "${BACKUP_RETENTION}" | sed -e 's/[mhdM]$//') TIME_UNIT=$(echo "${BACKUP_RETENTION}" | sed -e 's/^[0-9]\+//') if [ "${TIME_UNIT}" = "m" ]; then if [ "${TIME_INTERVAL}" -le 59 ]; then echo "Warning: Minimal retention is 60m. Value set to 60m" 1>&2 TIME_INTERVAL=60 fi FIND_TIME_EXPR="mmin" elif [ "${TIME_UNIT}" = "h" ]; then echo "Error: Unsupported expression - Try: eg. 120m for 2 hours." 1>&2 exit 1 elif [ "${TIME_UNIT}" = "d" ]; then FIND_TIME_EXPR="mtime" elif [ "${TIME_UNIT}" = "M" ]; then echo "Error: Unsupported expression - Try: eg. 60d for 2 months." 1>&2 exit 1 else echo "Parse error: BACKUP_RETENTION expression is invalid" 1>&2 exit 1 fi echo "${FIND_TIME_EXPR} +${TIME_INTERVAL:-7}" } add_backup_cronjob() { CRONTAB_USER="${1:-git}" CRONTAB_FILE="/etc/crontabs/${CRONTAB_USER}" CRONJOB_EXPRESSION="${2:-}" CRONJOB_EXECUTOR="${3:-}" CRONJOB_EXECUTOR_ARGUMENTS="${4:-}" CRONJOB_TASK="${CRONJOB_EXPRESSION} /bin/sh ${CRONJOB_EXECUTOR} ${CRONJOB_EXECUTOR_ARGUMENTS}" if [ -f "${CRONTAB_FILE}" ]; then CRONJOB_EXECUTOR_COUNT=$(grep -c "${CRONJOB_EXECUTOR}" "${CRONTAB_FILE}" || exit 0) if [ "${CRONJOB_EXECUTOR_COUNT}" != "0" ]; then echo "Cron job already exists for ${CRONJOB_EXECUTOR}. Updating existing." 1>&2 CRONJOB_TASK=$(echo "{CRONJOB_TASK}" | sed 's/\//\\\//g' ) CRONJOB_EXECUTOR=$(echo "{CRONJOB_EXECUTOR}" | sed 's/\//\\\//g' ) sed -i "/${CRONJOB_EXECUTOR}/c\\${CRONJOB_TASK}" "${CRONTAB_FILE}" return 0 fi fi # Finally append new line with cron task expression echo "${CRONJOB_TASK}" >>"${CRONTAB_FILE}" } CRONTAB_USER=$(awk -v val="${PUID}" -F ":" '$3==val{print $1}' /etc/passwd) # Up to this point, it was desirable that interpreter handles the command errors and halts execution upon any error. # From now, we handle the errors our self. set +e RETENTION_EXPRESSION="$(parse_generate_retention_expression)" if [ -z "${RETENTION_EXPRESSION}" ]; then echo "Couldn't generate backup retention expression. Aborting backup setup" 1>&2 exit 1 fi # Backup rotator cron will run every 5 minutes add_backup_cronjob "${CRONTAB_USER}" "*/5 * * * *" "/app/gogs/docker/runtime/backup-rotator.sh" "'${BACKUP_PATH}' '${RETENTION_EXPRESSION}'" add_backup_cronjob "${CRONTAB_USER}" "$(parse_generate_cron_expression)" "/app/gogs/docker/runtime/backup-job.sh" "'${BACKUP_PATH}'"