backup-notify/scheduler/scheduler.go

package scheduler

import (
	"database/sql"
	"log"
	"strings"
	"time"

	"git.simponic.xyz/simponic/backup-notify/args"
	"git.simponic.xyz/simponic/backup-notify/database"
	"git.simponic.xyz/simponic/backup-notify/ntfy"
	"github.com/go-co-op/gocron"
)

func contains(hostnames []string, hostname string) bool {
	for _, h := range hostnames {
		if h == hostname {
			return true
		}
	}
	return false
}

func StartScheduler(dbConn *sql.DB, argv *args.Arguments) {
	scheduler := gocron.NewScheduler(time.Local)

	scheduler.Every(1).Hour().Do(func() {
		err := database.DeleteOldBackups(dbConn, 31)
		if err != nil {
			log.Println("could not delete old backups:", err)
		}
	})

	scheduler.Every(1).Day().Do(func() {
		hostnames, err := database.BackupedHostnamesInTheLastDay(dbConn)
		if err != nil {
			log.Println("could not list hostnames that have been backed up in the last day:", err)
		}

		allHostnames, err := database.ReceivedHostnames(dbConn)
		if err != nil {
			log.Println("could not list received hostnames:", err)
		}

		failedHostnames := []string{}
		for _, hostname := range allHostnames {
			if !contains(hostnames, hostname) {
				failedHostnames = append(failedHostnames, hostname)
			}
		}

		if len(failedHostnames) > 0 {
			msg := "the following hostnames have not been backed up in the last day:\n" + strings.Join(failedHostnames, ", ")
			log.Println(msg)

			err := ntfy.SendMessage(msg, argv.NtfyEndpoint, argv.NtfyAlertTopics)
			if err != nil {
				log.Println("could not send alert:", err)
			}
		}
	})

	scheduler.StartAsync()
}