backup-notify/database/backups.go

package database

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

type Backup struct {
	Hostname   string
	ReceivedOn time.Time
}

func ListBackups(dbConn *sql.DB) ([]Backup, error) {
	log.Println("listing backups")

	rows, err := dbConn.Query(`SELECT hostname, received_on FROM backups;`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	backups := []Backup{}
	for rows.Next() {
		var backup Backup
		err := rows.Scan(&backup.Hostname, &backup.ReceivedOn)
		if err != nil {
			return nil, err
		}
		backups = append(backups, backup)
	}

	return backups, nil
}

func DeleteOldBackups(dbConn *sql.DB, days int) error {
	log.Println("deleting old backups")

	duration := time.Duration(days) * 24 * time.Hour
	_, err := dbConn.Exec(`DELETE FROM backups WHERE received_on < ?;`, time.Now().Add(-duration))

	return err
}

func ReceivedBackup(dbConn *sql.DB, hostname string) error {
	log.Println("received backup for", hostname)

	_, err := dbConn.Exec(`INSERT INTO backups (hostname) VALUES (?);`, hostname)

	return err
}

func BackupedHostnamesInTheLastDay(dbConn *sql.DB) ([]string, error) {
	log.Println("listing hostnames that have been backed up in the last day")

	rows, err := dbConn.Query(`SELECT DISTINCT hostname FROM backups WHERE received_on > ?;`, time.Now().Add(-24*time.Hour))
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	hostnames := []string{}
	for rows.Next() {
		var hostname string
		err := rows.Scan(&hostname)
		if err != nil {
			return nil, err
		}
		hostnames = append(hostnames, hostname)
	}

	return hostnames, nil
}

func ReceivedHostnames(dbConn *sql.DB) ([]string, error) {
	log.Println("listing received hostnames")

	rows, err := dbConn.Query(`SELECT DISTINCT hostname FROM backups;`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	hostnames := []string{}
	for rows.Next() {
		var hostname string
		err := rows.Scan(&hostname)
		if err != nil {
			return nil, err
		}
		hostnames = append(hostnames, hostname)
	}

	return hostnames, nil
}