timeouts_deadlines.md

Timeouts and Deadlines

The queue library offers mechanisms for precise control over job execution times, enhancing resource efficiency and ensuring tasks complete within expected timeframes.

Timeouts

Timeouts cap the execution duration of jobs to prevent them from running indefinitely. Exceeding the timeout causes the job to terminate and be marked as failed.

Implementing Timeouts

To set a job execution timeout, use the WithJobTimeout option when defining your job handler.

import (
    "context"
    "github.com/kaptinlin/queue"
    "time"
)

func EmailJobHandler(ctx context.Context, job *queue.Job) error {
    // Define job logic here
    return nil
}

// Create a handler for email jobs with a 30-second execution timeout
handler := queue.NewHandler(
    "email_job",
    EmailJobHandler,
    queue.WithJobTimeout(30*time.Second),
)

Deadlines

Deadlines determine the latest time a job can start. Jobs not initiated before their deadline are not processed.

Setting Deadlines

Apply a deadline to a job using the WithDeadline option during job creation to enforce its start time.

deadline := time.Now().Add(24 * time.Hour) // Set a 24-hour deadline

// Create a job with a specific deadline
job := queue.NewJob(
    "report_generation",
    map[string]interface{}{"reportId": 123},
    queue.WithDeadline(&deadline),
)

// Enqueue the job, handling any errors
id, err := client.EnqueueJob(job)
if err != nil {
    log.Fatalf("Failed to enqueue job: %v", err)
}