Building a Cron-Based Task Runner in Go With JSON Configs

If you’ve ever needed to automate scheduled tasks like sending reports, syncing data, or cleaning up logs — but didn’t want to pull in a full-blown task queue — Go and a little cron logic can get you surprisingly far.

Why Use a Custom Task Runner?

• 🔁 Fine-grained control over scheduling
• 🔧 Lightweight and embeddable
• 📄 Easy to configure via JSON

Step 1: Define Your Task Model

Create a simple task.json file that defines what needs to run and when:

[
  {
    "name": "daily_report",
    "schedule": "0 9 * * *",
    "command": "generate-report"
  },
  {
    "name": "cleanup_logs",
    "schedule": "30 2 * * 1",
    "command": "clear-logs"
  }
]

Step 2: Load Tasks From JSON

type Task struct {
    Name     string `json:"name"`
    Schedule string `json:"schedule"`
    Command  string `json:"command"`
}

func LoadTasks(filename string) ([]Task, error) {
    data, err := os.ReadFile(filename)
    if err != nil {
        return nil, err
    }

    var tasks []Task
    if err := json.Unmarshal(data, &tasks); err != nil {
        return nil, err
    }
    return tasks, nil
}