What causes "db Cannot be empty" in flipped-aurora/gin-vue-admin?

Ensure the database initializes successfully at startup (check config.yaml DSN and startup logs for init errors).

db Cannot be empty

Error message

db Cannot be empty

What it means

The ClearTable timed task deletes rows older than a configured interval from ClearTableDetail tables. Before executing, it validates that the injected *gorm.DB is non-nil; if nil, it returns errors.New("db Cannot be empty"). This prevents nil-pointer panics when the task runs without a database connection.

Source

Thrown at server/task/clearTable.go:40

		TableName:    "sys_operation_records",
		CompareField: "created_at",
		Interval:     "2160h",
	})

	ClearTableDetail = append(ClearTableDetail, common.ClearDB{
		TableName:    "jwt_blacklists",
		CompareField: "created_at",
		Interval:     "168h",
	})

	ClearTableDetail = append(ClearTableDetail, common.ClearDB{
		TableName:    "sys_timed_task_logs",
		CompareField: "created_at",
		Interval:     "720h", // 执行日志保留 30 天
	})

	if db == nil {
		return errors.New("db Cannot be empty")
	}

	for _, detail := range ClearTableDetail {
		duration, err := time.ParseDuration(detail.Interval)
		if err != nil {
			return err
		}
		if duration < 0 {
			return errors.New("parse duration < 0")
		}
		err = db.Debug().Exec(fmt.Sprintf("DELETE FROM %s WHERE %s < ?", detail.TableName, detail.CompareField), time.Now().Add(-duration)).Error
		if err != nil {
			return err
		}
	}
	return nil
}

View on GitHub (pinned to 3136500ef3)

Solutions

Ensure the database initializes successfully at startup (check config.yaml DSN and startup logs for init errors).
Pass a valid *gorm.DB (e.g. global.GVA_DB) when invoking ClearTable from a custom runner.
In tests, initialize the DB (e.g. testutil.NewMemoryDB) before invoking the task.
Do not enable the timed task until DB init is confirmed.

Example fix

// before
ClearTable(nil) // task runner without db
// after
if global.GVA_DB != nil { ClearTable(global.GVA_DB) }

Defensive patterns

Strategy: validation

Validate before calling

// guard before invoking the task
if global.GVA_DB == nil {
  return errors.New("database not initialized; skip ClearTable")
}
ClearTable(global.GVA_DB)

Type guard

func dbReady(db *gorm.DB) bool { return db != nil }

Try / catch

if err := ClearTable(db); err != nil {
  if err.Error() == "db Cannot be empty" {
    logger.Error("ClearTable ran without a DB handle; check startup init")
  }
  return err
}

Prevention

Verify DB initialization succeeded in startup logs before enabling timed tasks.
In tests, initialize a memory DB (testutil.NewMemoryDB) before invoking tasks.
Never call ClearTable with a nil or zero-value *gorm.DB.

When it happens

Trigger: Registering/running the ClearTable task (clearTable.go:40) when the *gorm.DB parameter passed in is nil — typically because the task was invoked without a DB argument or the DB was never initialized (config missing, connection failed) before task execution.

Common situations: Task invoked in unit tests without setting global.GVA_DB; DB initialization failed silently at startup (bad DSN) and the nil handle propagated; custom task runners passing no db argument.

Related errors

AI-assisted analysis of flipped-aurora/gin-vue-admin@3136500ef3 (2026-08-31). Data as JSON: /api/errors/ebedefec5e2d3f93. Report an issue: GitHub.