fix: radio discovery blocking program

pkg/radio/hub.go

@@ -41,16 +41,31 @@ func (h *Hub) NewRadios() ([]*Radio, error) {
 		return nil, err
 	}
 
-	// Create radios array
-	var radios []*Radio
+	rds := make(chan *Radio)
+	var wg sync.WaitGroup
+
 	for i := range clients {
-		radio, err := h.NewRadio(clients[i])
-		if err != nil {
-			log.Println("Hub.NewRadios(ERROR):", err)
-			continue
-		}
+		wg.Add(1)
+
+		go (func(idx int) {
+			radio, err := h.NewRadio(clients[idx])
+			if err != nil {
+				log.Println("Hub.NewRadios(ERROR):", err)
+			} else {
+				rds <- radio
+			}
+			wg.Done()
+		})(i)
+	}
 
-		radios = append(radios, radio)
+	go (func() {
+		wg.Wait()
+		close(rds)
+	})()
+
+	var radios []*Radio
+	for r := range rds {
+		radios = append(radios, r)
 	}
 
 	return radios, nil
@@ -85,6 +100,13 @@ func (h *Hub) NewRadio(client goupnp.ServiceClient) (*Radio, error) {
 		updateVolumeChan: make(chan int),
 		refreshPresets:   make(chan bool, 1),
 	}
+
+	err = rd.initState()
+	if err != nil {
+		cancel()
+		return nil, err
+	}
+
 	go rd.radioLoop()
 
 	return &rd, nil
@@ -185,6 +207,7 @@ func (h *Hub) discoverLoop() {
 			radios, err := h.NewRadios()
 			if err != nil {
 				d <- err
+				continue
 			}
 
 			// Create new radios map

pkg/radio/radio.go

@@ -3,7 +3,9 @@ package radio
 import (
 	"context"
 	"encoding/xml"
+	"fmt"
 	"log"
+	"strconv"
 
 	"github.com/avast/retry-go"
 )
@@ -64,8 +66,6 @@ func (rd *Radio) Refresh() {
 func (rd *Radio) radioLoop() {
 	log.Println("Radio.radioLoop: started")
 
-	rd.initState()
-
 	for {
 		select {
 		case <-rd.ctx.Done():
@@ -184,7 +184,7 @@ func (rd *Radio) sendState(state *State) {
 	rd.h.emitState(state)
 }
 
-func (rd *Radio) initState() {
+func (rd *Radio) initState() error {
 	// Set name of radio
 	rd.state.Name = rd.Client.RootDevice.Device.FriendlyName
 
@@ -198,11 +198,11 @@ func (rd *Radio) initState() {
 			return nil
 		}
 	}, retry.Context(rd.ctx)); err != nil {
-		log.Println("Radio.initState(ERROR):", err)
+		return err
 	} else {
 		numPresets = numPresets - 2
 		if numPresets < 1 {
-			log.Println("Radio.initState(ERROR): invalid number of presets were given from radio,", numPresets)
+			return fmt.Errorf("invalid number of presets were given from radio, " + strconv.Itoa(numPresets))
 		} else {
 			rd.state.NumPresets = numPresets
 		}
@@ -218,7 +218,7 @@ func (rd *Radio) initState() {
 			return nil
 		}
 	}, retry.Context(rd.ctx)); err != nil {
-		log.Println("Radio.initState(ERROR):", err)
+		return err
 	} else {
 		rd.state.Volume = &volume
 	}
@@ -233,11 +233,13 @@ func (rd *Radio) initState() {
 			return nil
 		}
 	}, retry.Context(rd.ctx)); err != nil {
-		log.Println("Radio.initState(ERROR):", err)
+		return err
 	} else {
 		for i := range presets {
 			rd.h.PresetMutator(rd.ctx, &presets[i])
 		}
 		rd.state.Presets = presets
 	}
+
+	return nil
 }