xmr-remote-nodes/internal/repo/cron.go

package repo

import (
	"fmt"
	"log/slog"
	"math"
	"time"
	"xmr-remote-nodes/internal/database"
)

type CronRepository interface {
	RunCronProcess()
	Crons() ([]Cron, error)
}

type CronRepo struct {
	db *database.DB
}

type Cron struct {
	Id          int     `json:"id" db:"id"`
	Title       string  `json:"title" db:"title"`
	Slug        string  `json:"slug" db:"slug"`
	Description string  `json:"description" db:"description"`
	RunEvery    int     `json:"run_every" db:"run_every"`
	LastRun     int64   `json:"last_run" db:"last_run"`
	NextRun     int64   `json:"next_run" db:"next_run"`
	RunTime     float64 `json:"run_time" db:"run_time"`
	CronState   int     `json:"cron_state" db:"cron_state"`
	IsEnabled   int     `json:"is_enabled" db:"is_enabled"`
}

var rerunTimeout = 300

func NewCron(db *database.DB) CronRepository {
	return &CronRepo{db}
}

func (repo *CronRepo) RunCronProcess() {
	for {
		time.Sleep(60 * time.Second)
		slog.Info("[CRON] Running cron cycle...")
		list, err := repo.queueList()
		if err != nil {
			slog.Warn(fmt.Sprintf("[CRON] Error parsing queue list to struct: %s", err))
			continue
		}
		for _, task := range list {
			startTime := time.Now()
			currentTs := startTime.Unix()
			delayedTask := currentTs - task.NextRun
			if task.CronState == 1 && delayedTask <= int64(rerunTimeout) {
				slog.Debug(fmt.Sprintf("[CRON] Skipping task %s because it is already running", task.Slug))
				continue
			}

			repo.preRunTask(task.Id, currentTs)

			repo.execCron(task.Slug)

			runTime := math.Ceil(time.Since(startTime).Seconds()*1000) / 1000
			slog.Info(fmt.Sprintf("[CRON] Task %s done in %f seconds", task.Slug, runTime))
			nextRun := currentTs + int64(task.RunEvery)

			repo.postRunTask(task.Id, nextRun, runTime)
		}
		slog.Info("[CRON] Cron cycle done!")
	}
}

func (repo *CronRepo) Crons() ([]Cron, error) {
	query := `SELECT id, title, slug, description, run_every, last_run, next_run, run_time, cron_state, is_enabled FROM tbl_cron`

	var tasks []Cron
	err := repo.db.Select(&tasks, query)
	return tasks, err
}

func (repo *CronRepo) queueList() ([]Cron, error) {
	tasks := []Cron{}
	query := `SELECT id, run_every, last_run, slug, next_run, cron_state FROM tbl_cron
    WHERE is_enabled = ? AND next_run <= ?`
	err := repo.db.Select(&tasks, query, 1, time.Now().Unix())

	return tasks, err
}

func (repo *CronRepo) preRunTask(id int, lastRunTs int64) {
	query := `UPDATE tbl_cron SET cron_state = ?, last_run = ? WHERE id = ?`
	row, err := repo.db.Query(query, 1, lastRunTs, id)
	if err != nil {
		slog.Error(fmt.Sprintf("[CRON] Failed to update pre cron state: %s", err))
	}
	defer row.Close()
}

func (repo *CronRepo) postRunTask(id int, nextRun int64, runtime float64) {
	query := `UPDATE tbl_cron SET cron_state = ?, next_run = ?, run_time = ? WHERE id = ?`
	row, err := repo.db.Query(query, 0, nextRun, runtime, id)
	if err != nil {
		slog.Error(fmt.Sprintf("[CRON] Failed to update post cron state: %s", err))
	}
	defer row.Close()
}

func (repo *CronRepo) execCron(slug string) {
	switch slug {
	case "delete_old_probe_logs":
		slog.Info(fmt.Sprintf("[CRON] Start running task: %s", slug))
		repo.deleteOldProbeLogs()
		break
	}
}

func (repo *CronRepo) deleteOldProbeLogs() {
	// for now, we only delete stats older than 1 month +2 days
	startTs := time.Now().AddDate(0, -1, -2).Unix()
	query := `DELETE FROM tbl_probe_log WHERE date_checked < ?`
	_, err := repo.db.Exec(query, startTs)
	if err != nil {
		slog.Error(fmt.Sprintf("[CRON] Failed to delete old probe logs: %s", err))
	}
}