scheduler.md

Scheduler Documentation

The Scheduler enables scheduled job execution at specified intervals or according to cron expressions, facilitating routine operations such as nightly backups, weekly report generation, or periodic data synchronization tasks.

Setup

Start with a valid Redis configuration. Initialize the Scheduler with necessary options like the time zone:

redisConfig := queue.NewRedisConfig(
    queue.WithRedisAddress("localhost:6379"), // Specify your Redis server address
    // Additional configuration options as needed...
)

scheduler, err := queue.NewScheduler(redisConfig,
    queue.WithSchedulerLocation(time.UTC), // Adjust the time zone as needed
)
if err != nil {
    log.Fatal("Scheduler creation failed:", err)
}

Configuring Hooks for Job Lifecycle Management

Pre-Enqueue Hook

Incorporate custom logic prior to job enqueuing:

scheduler.WithPreEnqueueFunc(func(job *queue.Job) {
    // Insert pre-enqueue operations here
    log.Printf("Job preparation: %s\n", job.Type)
})

Post-Enqueue Hook

Execute follow-up actions after job enqueuing, especially for error handling:

scheduler.WithPostEnqueueFunc(func(job *queue.JobInfo, err error) {
    if err != nil {
        log.Printf("Enqueue failed for job: %s, error: %v\n", job.Type, err)
    } else {
        log.Printf("Job enqueued successfully: %s\n", job.Type)
    }
})

Job Scheduling

Cron Jobs

For scheduling jobs based on cron expressions:

jobType := "report:generate"
payload := map[string]interface{}{"reportType": "weekly"}
cronExpression := "0 9 * * 1" // Example: Every Monday at 9:00 AM

_, err = scheduler.RegisterCron(cronExpression, jobType, payload)
if err != nil {
    log.Fatalf("Cron job scheduling failed: %v", err)
}

Periodic Jobs

For interval-based job scheduling:

jobType := "status:check"
payload := map[string]interface{}{"target": "database"}
interval := 15 * time.Minute // Example: Every 15 minutes

_, err = scheduler.RegisterPeriodic(interval, jobType, payload)
if err != nil {
    log.Fatalf("Periodic job scheduling failed: %v", err)
}

Scheduler Operations

Starting the Scheduler:

if err := scheduler.Start(); err != nil {
    log.Fatal("Starting scheduler failed:", err)
}

Stopping the Scheduler:

if err := scheduler.Stop(); err != nil {
    log.Println("Scheduler shutdown error:", err)
}