can send messages back to specific and ALL viewers

src/device/input/button/v01.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"log"
 	"mayhem-party/src/device/input/raw"
+	"net/http"
 	"os"
 	"time"
 
@@ -31,6 +32,9 @@ type (
 		N string
 	}
 	v01Cfg struct {
+		Feedback struct {
+			Addr string
+		}
 		Users map[string]struct {
 			Player  int
 			Message string
@@ -47,12 +51,41 @@ func NewV01(ctx context.Context, src raw.Raw) V01 {
 	b, _ := ioutil.ReadFile(FlagButtonV01Config)
 	yaml.Unmarshal(b, &cfg)
 	ctx, can := context.WithCancel(ctx)
-	return V01{
+	result := V01{
 		ctx: ctx,
 		can: can,
 		src: src,
 		cfg: cfg,
 	}
+	go result.listen()
+	return result
+}
+
+func (v01 V01) listen() {
+	if v01.cfg.Feedback.Addr == "" {
+		return
+	}
+	s := &http.Server{
+		Addr: v01.cfg.Feedback.Addr,
+		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			r = r.WithContext(v01.ctx)
+			user, ok := v01.cfg.Users[r.URL.Query().Get("user")]
+			if !ok {
+				user = v01.cfg.Users["broadcast"]
+			}
+			w.Write([]byte(user.Message))
+		}),
+	}
+	go func() {
+		<-v01.ctx.Done()
+		log.Println("closing v01 server")
+		s.Close()
+	}()
+	log.Println("starting v01 server")
+	if err := s.ListenAndServe(); err != nil && v01.ctx.Err() == nil {
+		log.Println("err with v01 server", err)
+		panic(err)
+	}
 }
 
 func (v01 V01) CloseWrap() raw.Raw {

src/device/input/button/v01_exported_test.go

@@ -3,7 +3,9 @@ package button_test
 import (
 	"context"
 	"fmt"
+	"io"
 	"mayhem-party/src/device/input/button"
+	"net/http"
 	"os"
 	"path"
 	"testing"
@@ -14,6 +16,7 @@ func TestV01(t *testing.T) {
 	src := constSrc(fmt.Sprintf(`{"T":%v,"U":"bel","Y":"abc","N":"cde"}`, time.Now().UnixNano()/int64(time.Millisecond)-50))
 	t.Logf("(%v) %s", len(src), src.Read())
 	v01 := button.NewV01(context.Background(), src)
+	defer v01.Close()
 	got := v01.Read()
 	want := []button.Button{
 		{Down: true, Char: 'a'},
@@ -50,6 +53,7 @@ func TestV01WithCfg(t *testing.T) {
 
 	t.Run("unknown user ignored", func(t *testing.T) {
 		v01 := button.NewV01(context.Background(), constSrc(`{"U":"qt","Y":"w"}`))
+		defer v01.Close()
 		got := v01.Read()
 		if len(got) != 0 {
 			t.Error(got)
@@ -58,6 +62,7 @@ func TestV01WithCfg(t *testing.T) {
 
 	t.Run("player2", func(t *testing.T) {
 		v01 := button.NewV01(context.Background(), constSrc(`{"U":"bel","Y":"w","N":"w"}`))
+		defer v01.Close()
 		got := v01.Read()
 		if len(got) != 2 {
 			t.Error(got)
@@ -70,3 +75,63 @@ func TestV01WithCfg(t *testing.T) {
 		}
 	})
 }
+
+func TestV01Feedback(t *testing.T) {
+	d := t.TempDir()
+	p := path.Join(d, "cfg.yaml")
+	os.WriteFile(p, []byte(`
+      feedback:
+        addr: :27071
+      users:
+        bel:
+          player: 2
+          message: to bel
+        broadcast:
+          message: to everyone
+      players:
+      - transformation:
+          w: t
+      - transformation:
+          w: i
+   `), os.ModePerm)
+	button.FlagButtonV01Config = p
+	ctx, can := context.WithCancel(context.Background())
+	defer can()
+
+	v01 := button.NewV01(ctx, constSrc(`{"U":"qt","Y":"w"}`))
+	defer v01.Close()
+
+	for {
+		time.Sleep(time.Millisecond * 100)
+		resp, err := http.Get("http://localhost:27071?user=bel")
+		if err != nil {
+			continue
+		}
+		resp.Body.Close()
+		break
+	}
+
+	t.Run("specific user", func(t *testing.T) {
+		resp, err := http.Get("http://localhost:27071?user=bel")
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer resp.Body.Close()
+		b, _ := io.ReadAll(resp.Body)
+		if string(b) != "to bel" {
+			t.Error(b)
+		}
+	})
+
+	t.Run("broadcast", func(t *testing.T) {
+		resp, err := http.Get("http://localhost:27071")
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer resp.Body.Close()
+		b, _ := io.ReadAll(resp.Body)
+		if string(b) != "to everyone" {
+			t.Error(b)
+		}
+	})
+}