Prevent concurrent writes on the same websocket.

This was causing occasional UI glitches.

alliance_station_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 	"time"
 )
@@ -40,7 +41,7 @@ func TestAllianceStationDisplayWebsocket(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/alliance_station/websocket?displayId=1", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Should get a few status updates right after connection.
 	readWebsocketType(t, ws, "setAllianceStationDisplay")

announcer_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 	"time"
 )
@@ -40,7 +41,7 @@ func TestAnnouncerDisplayWebsocket(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/announcer/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Should get a few status updates right after connection.
 	readWebsocketType(t, ws, "setMatch")

audience_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 )
 
@@ -39,7 +40,7 @@ func TestAudienceDisplayWebsocket(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/audience/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Should get a few status updates right after connection.
 	readWebsocketType(t, ws, "matchTiming")

match_play_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/mitchellh/mapstructure"
 	"github.com/stretchr/testify/assert"
 	"log"
+	"sync"
 	"testing"
 	"time"
 )
@@ -277,7 +278,7 @@ func TestMatchPlayWebsocketCommands(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/match_play/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Should get a few status updates right after connection.
 	readWebsocketType(t, ws, "status")
@@ -372,7 +373,7 @@ func TestMatchPlayWebsocketNotifications(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/match_play/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Should get a few status updates right after connection.
 	readWebsocketType(t, ws, "status")

pit_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 )
 
@@ -38,7 +39,7 @@ func TestPitDisplayWebsocket(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/pit/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Check forced reloading as that is the only purpose the pit websocket serves.
 	recorder := getHttpResponse("/setup/field/reload_displays")

referee_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 	"time"
 )
@@ -40,7 +41,7 @@ func TestRefereeDisplayWebsocket(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/referee/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	// Test foul addition.
 	foulData := struct {

scoring_display_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 )
 
@@ -46,11 +47,11 @@ func TestScoringDisplayWebsocket(t *testing.T) {
 	redConn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/scoring/red/websocket", nil)
 	assert.Nil(t, err)
 	defer redConn.Close()
-	redWs := &Websocket{redConn}
+	redWs := &Websocket{redConn, new(sync.Mutex)}
 	blueConn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/displays/scoring/blue/websocket", nil)
 	assert.Nil(t, err)
 	defer blueConn.Close()
-	blueWs := &Websocket{blueConn}
+	blueWs := &Websocket{blueConn, new(sync.Mutex)}
 
 	// Should receive a score update right after connection.
 	readWebsocketType(t, redWs, "score")

setup_lower_thirds_test.go

@@ -6,6 +6,7 @@ package main
 import (
 	"github.com/gorilla/websocket"
 	"github.com/stretchr/testify/assert"
+	"sync"
 	"testing"
 	"time"
 )
@@ -34,7 +35,7 @@ func TestSetupLowerThirds(t *testing.T) {
 	conn, _, err := websocket.DefaultDialer.Dial(wsUrl+"/setup/lower_thirds/websocket", nil)
 	assert.Nil(t, err)
 	defer conn.Close()
-	ws := &Websocket{conn}
+	ws := &Websocket{conn, new(sync.Mutex)}
 
 	ws.Write("saveLowerThird", LowerThird{1, "Top Text 4", "Bottom Text 1", 0})
 	time.Sleep(time.Millisecond * 10) // Allow some time for the command to be processed.

tba.go

@@ -279,7 +279,7 @@ func PublishMatches() error {
 
 		tbaMatches[i] = TbaMatch{"qm", 0, matchNumber, map[string]interface{}{"red": redAlliance,
 			"blue": blueAlliance}, scoreBreakdown, match.Time.Local().Format("3:04 PM"),
-			match.Time.Format("2006-01-02T15:04:05")}
+			match.Time.UTC().Format("2006-01-02T15:04:05")}
 		if match.Type == "elimination" {
 			tbaMatches[i].CompLevel = map[int]string{1: "f", 2: "sf", 4: "qf", 8: "ef"}[match.ElimRound]
 			tbaMatches[i].SetNumber = match.ElimGroup

web.go

@@ -12,6 +12,7 @@ import (
 	"github.com/gorilla/websocket"
 	"log"
 	"net/http"
+	"sync"
 	"text/template"
 )
 
@@ -44,7 +45,8 @@ var templateHelpers = template.FuncMap{
 
 // Wraps the Gorilla Websocket module so that we can define additional functions on it.
 type Websocket struct {
-	conn *websocket.Conn
+	conn       *websocket.Conn
+	writeMutex *sync.Mutex
 }
 
 type WebsocketMessage struct {
@@ -58,7 +60,7 @@ func NewWebsocket(w http.ResponseWriter, r *http.Request) (*Websocket, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &Websocket{conn}, nil
+	return &Websocket{conn, new(sync.Mutex)}, nil
 }
 
 func (websocket *Websocket) Close() {
@@ -72,14 +74,20 @@ func (websocket *Websocket) Read() (string, interface{}, error) {
 }
 
 func (websocket *Websocket) Write(messageType string, data interface{}) error {
+	websocket.writeMutex.Lock()
+	defer websocket.writeMutex.Unlock()
 	return websocket.conn.WriteJSON(WebsocketMessage{messageType, data})
 }
 
 func (websocket *Websocket) WriteError(errorMessage string) error {
+	websocket.writeMutex.Lock()
+	defer websocket.writeMutex.Unlock()
 	return websocket.conn.WriteJSON(WebsocketMessage{"error", errorMessage})
 }
 
 func (websocket *Websocket) ShowDialog(message string) error {
+	websocket.writeMutex.Lock()
+	defer websocket.writeMutex.Unlock()
 	return websocket.conn.WriteJSON(WebsocketMessage{"dialog", message})
 }