Read players from fifo.

cmd/mtwebmapper/players.go

@@ -1,14 +1,19 @@
 package main
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/json"
 	"html/template"
 	"log"
 	"net/http"
+	"os"
 	"sync"
+	"time"
 )
 
+const sleepInterval = time.Second * 5
+
 var geoJSONTmpl = template.Must(template.New("geojson").Parse(
 	`{ "type": "Feature",
   "geometry": {
@@ -21,10 +26,10 @@ var geoJSONTmpl = template.Must(template.New("geojson").Parse(
 }`))
 
 type player struct {
-	X    float64
+	X    float64 `json:"x"`
-	Y    float64
+	Y    float64 `json:"y"`
-	Z    float64
+	Z    float64 `json:"z"`
-	Name string
+	Name string  `json:"name"`
 }
 
 type players struct {
@@ -46,9 +51,33 @@ func (p *player) MarshalJSON() ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
+func (ps *players) readFromFIFO() ([]*player, error) {
+	file, err := os.Open(ps.fifo)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+	reader := bufio.NewReader(file)
+	decoder := json.NewDecoder(reader)
+	var pls []*player
+
+	if err = decoder.Decode(&pls); err != nil {
+		return nil, err
+	}
+	return pls, nil
+}
+
 func (ps *players) run() {
 	for {
-		// TODO: Implement me!
+		pls, err := ps.readFromFIFO()
+		if err != nil {
+			time.Sleep(sleepInterval)
+			continue
+		}
+		ps.mu.Lock()
+		ps.pls = pls
+		ps.mu.Unlock()
+		// TODO: Implement websocket broadcast.
 	}
 }