Asynq 

Asynq is a simple asynchronous task queue library in Go.

Requirements

• Redis: 2.6+
• Go: 1.12+

Installation

go get -u github.com/hibiken/asynq

Getting Started

1. Import asynq in your file.

import "github.com/hibiken/asynq"

2. Create a Client instance to create tasks.

func main() {
    client := asynq.NewClient(&asynq.RedisOpt{
        Addr: "localhost:6379",
    })

    t1 := &asynq.Task{
        Type: "send_welcome_email",
        Payload: map[string]interface{}{
          "recipient_id": 1234,
        },
    }

    t2 := &asynq.Task{
        Type: "send_reminder_email",
        Payload: map[string]interface{}{
          "recipient_id": 1234,
        },
    }

    // process the task immediately.
    client.Process(t1, time.Now())

    // process the task 24 hours later.
    client.Process(t2, time.Now().Add(24 * time.Hour))
}

3. Create a Background instance to process tasks.

func main() {
    bg := asynq.NewBackground(10, &asynq.RedisOpt{
        Addr: "localhost:6379",
    })

    bg.Run(asynq.HandlerFunc(handler))
}

// if handler returns an error or panics, the task will be retried after some delay.
func handler(t *Task) error {
    switch t.Type {
        case "send_welcome_email":
            rid, ok := t.Payload["recipient_id"]
            if !ok {
                return fmt.Errorf("recipient_id not found in payload")
            }
            fmt.Printf("Send Welcome Email to %d\n", rid.(int))

        // ... handle other task types.

        default:
            return fmt.Errorf("unexpected task type: %s", t.Type)
    }
    return nil
}