#!/bin/sh
# =============================================================================
# 備份還原驗證 CronJob — ADR-074 M4
# =============================================================================
# 每週日 02:00 台北執行 Velero restore dry-run，驗證 PVC 快照可讀取。
# 失敗時寫入 Prometheus textfile metrics → 觸發 BackupRestoreTestFailed 告警。
#
# Textfile 路徑：/var/lib/node_exporter/textfile_collector/backup_restore_test.prom
# （由 node-exporter --collector.textfile.directory 掃描）
#
# 2026-04-12 ogt (ADR-074 M4)
# =============================================================================

set -e

TEXTFILE="/var/lib/node_exporter/textfile_collector/backup_restore_test.prom"
NAMESPACE="${VELERO_NAMESPACE:-velero}"
BACKUP_NAME="${VELERO_BACKUP_NAME:-awoooi-daily}"
EXIT_CODE=0

echo "=== backup-restore-test: $(date '+%Y-%m-%d %H:%M:%S %Z') ==="
echo "Backup: ${BACKUP_NAME}  Namespace: ${NAMESPACE}"

# --- Velero restore dry-run ---
velero restore create \
  --from-backup "${BACKUP_NAME}" \
  --namespace-mappings "${NAMESPACE}:restore-test-dry" \
  --dry-run \
  --wait \
  2>&1 || EXIT_CODE=$?

# --- 寫入 textfile metric ---
# 注意：Prometheus textfile collector 不接受毫秒時間戳（13位），只接受秒（10位）
# 直接省略 timestamp，由 node-exporter scrape 時自動補上
TS=$(date +%s)
mkdir -p "$(dirname "${TEXTFILE}")"

if [ "${EXIT_CODE}" -eq 0 ]; then
  echo "backup restore dry-run OK"
  cat > "${TEXTFILE}" <<PROM
# HELP awoooi_backup_restore_test_success 1 = last backup restore dry-run succeeded
# TYPE awoooi_backup_restore_test_success gauge
awoooi_backup_restore_test_success 1
# HELP awoooi_backup_restore_test_timestamp_seconds Unix timestamp of last test run
# TYPE awoooi_backup_restore_test_timestamp_seconds gauge
awoooi_backup_restore_test_timestamp_seconds ${TS}
PROM
  echo "Textfile written: success"
  exit 0
else
  echo "backup restore dry-run FAILED (exit ${EXIT_CODE})"
  cat > "${TEXTFILE}" <<PROM
# HELP awoooi_backup_restore_test_success 1 = last backup restore dry-run succeeded
# TYPE awoooi_backup_restore_test_success gauge
awoooi_backup_restore_test_success 0
# HELP awoooi_backup_restore_test_timestamp_seconds Unix timestamp of last test run
# TYPE awoooi_backup_restore_test_timestamp_seconds gauge
awoooi_backup_restore_test_timestamp_seconds ${TS}
PROM
  echo "Textfile written: failure"
  exit 1
fi