Fix: immediately update provider when modtime too old

adapter/provider/fetcher.go

@@ -21,6 +21,7 @@ type parser = func([]byte) (any, error)
 type fetcher struct {
 	name      string
 	vehicle   types.Vehicle
+	interval  time.Duration
 	updatedAt *time.Time
 	ticker    *time.Ticker
 	done      chan struct{}
@@ -42,12 +43,14 @@ func (f *fetcher) Initial() (any, error) {
 		buf               []byte
 		err               error
 		isLocal           bool
+		immediatelyUpdate bool
 	)
 	if stat, fErr := os.Stat(f.vehicle.Path()); fErr == nil {
 		buf, err = os.ReadFile(f.vehicle.Path())
 		modTime := stat.ModTime()
 		f.updatedAt = &modTime
 		isLocal = true
+		immediatelyUpdate = time.Since(modTime) > f.interval
 	} else {
 		buf, err = f.vehicle.Read()
 	}
@@ -86,7 +89,7 @@ func (f *fetcher) Initial() (any, error) {
 
 	// pull proxies automatically
 	if f.ticker != nil {
-		go f.pullLoop()
+		go f.pullLoop(immediatelyUpdate)
 	}
 
 	return proxies, nil
@@ -130,25 +133,33 @@ func (f *fetcher) Destroy() error {
 	return nil
 }
 
-func (f *fetcher) pullLoop() {
-	for {
-		select {
-		case <-f.ticker.C:
+func (f *fetcher) pullLoop(immediately bool) {
+	update := func() {
 		elm, same, err := f.Update()
 		if err != nil {
 			log.Warnln("[Provider] %s pull error: %s", f.Name(), err.Error())
-				continue
+			return
 		}
 
 		if same {
 			log.Debugln("[Provider] %s's proxies doesn't change", f.Name())
-				continue
+			return
 		}
 
 		log.Infoln("[Provider] %s's proxies update", f.Name())
 		if f.onUpdate != nil {
 			f.onUpdate(elm)
 		}
+	}
+
+	if immediately {
+		update()
+	}
+
+	for {
+		select {
+		case <-f.ticker.C:
+			update()
 		case <-f.done:
 			f.ticker.Stop()
 			return
@@ -178,6 +189,7 @@ func newFetcher(name string, interval time.Duration, vehicle types.Vehicle, pars
 		name:     name,
 		ticker:   ticker,
 		vehicle:  vehicle,
+		interval: interval,
 		parser:   parser,
 		done:     make(chan struct{}, 1),
 		onUpdate: onUpdate,