f-29: watchdog: create runner #29

Signed-off-by: GnomeZworc <nicolas.boufidjeline@g3e.fr>

internal/watchdog/watchdog.go

@@ -0,0 +1,90 @@
+package watchdog
+
+import (
+	"context"
+	"log/slog"
+	"time"
+
+	configuration "git.g3e.fr/syonad/two/internal/config/agent"
+	"git.g3e.fr/syonad/two/internal/watchdog/notify"
+	"git.g3e.fr/syonad/two/pkg/systemd"
+
+	"github.com/dgraph-io/badger/v4"
+)
+
+const defaultInterval = 60 * time.Second
+
+type Watchdog struct {
+	db       *badger.DB
+	cfg      *configuration.Config
+	notifier notify.Notifier
+	logger   *slog.Logger
+	interval time.Duration
+	dbusDown bool
+}
+
+func New(db *badger.DB, cfg *configuration.Config, n notify.Notifier, logger *slog.Logger, interval time.Duration) *Watchdog {
+	if logger == nil {
+		logger = slog.Default()
+	}
+	if interval <= 0 {
+		logger.Warn("watchdog: intervalle invalide, valeur par défaut appliquée",
+			"interval", interval, "default", defaultInterval)
+		interval = defaultInterval
+	}
+	return &Watchdog{
+		db:       db,
+		cfg:      cfg,
+		notifier: n,
+		logger:   logger,
+		interval: interval,
+	}
+}
+
+func (w *Watchdog) Run(ctx context.Context) {
+	ticker := time.NewTicker(w.interval)
+	defer ticker.Stop()
+
+	w.logger.Info("watchdog: démarrage", "interval", w.interval)
+
+	for {
+		select {
+		case <-ctx.Done():
+			w.logger.Info("watchdog: arrêt")
+			return
+		case <-ticker.C:
+			w.tick()
+		}
+	}
+}
+
+func (w *Watchdog) tick() {
+	u, closeUnits := w.units()
+	defer closeUnits()
+
+	if err := CheckVPCs(w.db, w.notifier); err != nil {
+		w.logger.Error("watchdog: vérification des vpc", "err", err)
+	}
+	if err := CheckSubnets(w.db, u, w.notifier); err != nil {
+		w.logger.Error("watchdog: vérification des subnets", "err", err)
+	}
+	if err := CheckVMs(w.db, w.cfg, u, w.notifier); err != nil {
+		w.logger.Error("watchdog: vérification des vm", "err", err)
+	}
+}
+
+func (w *Watchdog) units() (unitChecker, func()) {
+	m, err := systemd.New()
+	if err != nil {
+		if !w.dbusDown {
+			w.logger.Warn("watchdog: connexion systemd impossible, vérification des units désactivée", "err", err)
+			w.dbusDown = true
+		}
+		return nil, func() {}
+	}
+	if w.dbusDown {
+		w.logger.Info("watchdog: connexion systemd rétablie")
+		w.dbusDown = false
+	}
+	return m, m.Close
+}