Send players to websocket on connect.

cmd/mtwebmapper/forwardupdates.go

@@ -5,7 +5,6 @@
 package main
 
 import (
-	"bytes"
 	"encoding/json"
 	"log"
 	"net/http"
@@ -17,6 +16,7 @@ type websocketForwarder struct {
 	upgrader    *websocket.Upgrader
 	connections map[*connection]struct{}
 	funcs       chan func(*websocketForwarder)
+	init        func(*websocketForwarder, *connection)
 }
 
 type connection struct {
@@ -67,22 +67,24 @@ func (wsf *websocketForwarder) unregister(c *connection) {
 	}
 }
 
+func (wsf *websocketForwarder) setInit(init func(*websocketForwarder, *connection)) {
+	wsf.funcs <- func(wsf *websocketForwarder) {
+		wsf.init = init
+	}
+}
+
 func (wsf *websocketForwarder) send(m interface{}) {
 	wsf.funcs <- func(wsf *websocketForwarder) {
 		if len(wsf.connections) == 0 {
 			return
 		}
 
-		var buf bytes.Buffer
-
-		encoder := json.NewEncoder(&buf)
-		if err := encoder.Encode(m); err != nil {
-			log.Printf("encoding changes failed: %s\n", err)
+		data, err := json.Marshal(m)
+		if err != nil {
+			log.Printf("encoding failed. %v\n", err)
 			return
 		}
 
-		data := buf.Bytes()
-
 		for c := range wsf.connections {
 			select {
 			case c.send <- data:
@@ -94,6 +96,26 @@ func (wsf *websocketForwarder) send(m interface{}) {
 	}
 }
 
+func (wsf *websocketForwarder) singleSend(c *connection, m interface{}) {
+	wsf.funcs <- func(wsf *websocketForwarder) {
+		_, ok := wsf.connections[c]
+		if !ok {
+			return
+		}
+		data, err := json.Marshal(m)
+		if err != nil {
+			log.Printf("encoding failed. %v\n", err)
+			return
+		}
+		select {
+		case c.send <- data:
+		default:
+			delete(wsf.connections, c)
+			close(c.send)
+		}
+	}
+}
+
 func (wsf *websocketForwarder) BaseTilesUpdated(changes []xz) {
 	wsf.send(&tilesMsg{Tiles: changes})
 }
@@ -112,6 +134,9 @@ func (wsf *websocketForwarder) ServeHTTP(rw http.ResponseWriter, r *http.Request
 	wsf.register(c)
 	defer wsf.unregister(c)
 	go c.writer()
+	if wsf.init != nil {
+		wsf.init(wsf, c)
+	}
 	c.reader()
 }
 

cmd/mtwebmapper/main.go

@@ -59,7 +59,9 @@ func main() {
 
 	if cfg.PlayersFIFO != "" {
 		plys := newPlayers(cfg.PlayersFIFO, wsf)
+		wsf.setInit(plys.initConnection)
 		go plys.run()
+
 		router.Path("/players").Methods("GET").Handler(plys)
 	}
 

cmd/mtwebmapper/players.go

@@ -173,6 +173,10 @@ func (ps *players) current() []*player {
 	return ps.pls
 }
 
+func (ps *players) initConnection(wsf *websocketForwarder, c *connection) {
+	wsf.singleSend(c, &plsMsg{Pls: ps.current()})
+}
+
 func (ps *players) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
 	rw.Header().Set("Content-Type", "application/json")
 	pls := ps.current()