current song as server side event

README.md

@@ -1,5 +1 @@
 # schnutibox
-
-## TODO
-
-- raspi configuration script

assets/web/files/schnutibox.js

@@ -1,6 +1,6 @@
 if(typeof(EventSource) !== "undefined") {
-        var source = new EventSource("/log");
+        var logSource = new EventSource("/log");
-        source.onmessage = function(event) {
+        logSource.onmessage = function(event) {
                 var j = JSON.parse(event.data);
                 /* eslint-disable no-prototype-builtins */
                 if (j.hasOwnProperty("message")) {
@@ -11,6 +11,15 @@ if(typeof(EventSource) !== "undefined") {
         document.getElementById("log").innerHTML = "Sorry, your browser does not support server-sent events...";
 }
 
+if(typeof(EventSource) !== "undefined") {
+  var currentsongSource = new EventSource("/currentsong");
+  currentsongSource.onmessage = function(event){
+    document.getElementById("currentsong").innerHTML = event.data
+  };
+} else {
+        document.getElementById("currentsong").innerHTML = "Sorry, your browser does not support server-sent events...";
+};
+
 function handleSubmit(event, url) {
   event.preventDefault()
 

assets/web/templates/index.html.tmpl

@@ -11,6 +11,9 @@
                 <div class="container">
                         <h1>schnutibox</h1>
 
+			<h2>Currently playing</h2>
+			<div id="currentsong"></div>
+
 			<h2>Timer</h2>
 			Takes only seconds. Example: 600s
 			<form id="timerForm">

pkg/currentsong/currentsong.go

@@ -0,0 +1,56 @@
+package currentsong
+
+import (
+	"fmt"
+	"net/http"
+
+	"go.xsfx.dev/logginghandler"
+)
+
+var recvs = make(map[chan string]struct{}) // nolint:gochecknoglobals
+
+// Write writes current track to the receivers.
+func Write(track string) {
+	for k := range recvs {
+		k <- track
+	}
+}
+
+func Handler(w http.ResponseWriter, r *http.Request) {
+	logger := logginghandler.Logger(r)
+	logger.Debug().Msg("got a new receiver")
+
+	flusher, ok := w.(http.Flusher)
+	if !ok {
+		logger.Error().Msg("streaming unsupported")
+		http.Error(w, "streaming unsupported", http.StatusInternalServerError)
+
+		return
+	}
+
+	w.Header().Set("Content-Type", "text/event-stream")
+	w.Header().Set("Cache-Control", "no-cache")
+	w.Header().Set("Connection", "keep-alive")
+	// TODO: has to be something else!
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+
+	cChan := make(chan string)
+
+	recvs[cChan] = struct{}{}
+
+	for {
+		select {
+		case e := <-cChan:
+			// Send event to client.
+			fmt.Fprintf(w, "data: %s\n\n", e)
+
+			// Send it right now and not buffering it.
+			flusher.Flush()
+		case <-r.Context().Done():
+			close(cChan)
+			delete(recvs, cChan)
+
+			return
+		}
+	}
+}

pkg/watcher/watcher.go

@@ -1,10 +1,12 @@
 package watcher
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/rs/zerolog/log"
 	"go.xsfx.dev/schnutibox/internal/metrics"
+	"go.xsfx.dev/schnutibox/pkg/currentsong"
 	"go.xsfx.dev/schnutibox/pkg/mpc"
 	"go.xsfx.dev/schnutibox/pkg/timer"
 )
@@ -51,6 +53,20 @@ func Run() {
 					return
 				}
 
+				currentSong, err := m.CurrentSong()
+				if err != nil {
+					log.Error().Err(err).Msg("could not get current song")
+					metrics.BoxErrors.Inc()
+
+					return
+				}
+
+				if len(currentSong) != 0 {
+					currentsong.Write(fmt.Sprintf("%s - %s", currentSong["Artist"], currentSong["Track"]))
+				} else {
+					currentsong.Write("")
+				}
+
 				// Sets the metrics.
 				metrics.Set(uris, s["state"])
 			}()

pkg/web/web.go

@@ -17,6 +17,7 @@ import (
 	assets "go.xsfx.dev/schnutibox/assets/web"
 	"go.xsfx.dev/schnutibox/internal/config"
 	api "go.xsfx.dev/schnutibox/pkg/api/v1"
+	"go.xsfx.dev/schnutibox/pkg/currentsong"
 	"go.xsfx.dev/schnutibox/pkg/sselog"
 	"go.xsfx.dev/schnutibox/pkg/timer"
 	"golang.org/x/net/http2"
@@ -96,6 +97,8 @@ func (t TimerServer) Get(ctx context.Context, req *api.TimerEmpty) (*api.Timer,
 	return timer.T.Req, nil
 }
 
+func currentSong(w http.ResponseWriter, r *http.Request) {}
+
 func gw(s *grpc.Server, conn string) *runtime.ServeMux {
 	ctx := context.Background()
 	gopts := []grpc.DialOption{grpc.WithInsecure()}
@@ -133,6 +136,7 @@ func Run(command *cobra.Command, args []string) {
 	mux.Handle("/", http.HandlerFunc(root))
 
 	mux.Handle("/log", http.HandlerFunc(sselog.LogHandler))
+	mux.Handle("/currentsong", http.HandlerFunc(currentsong.Handler))
 
 	mux.Handle(
 		"/static/",