Fixing race conditions in the code base (#5966)

* Adding initial race detector

* Remove setting of config twice

* Fixing config file watch and config reload on license save

* Fixing config file watch and config reload on license save

* Fixing build error

* Fixing locking issue

* Fixing makefile

* Fixing race in config

* Fixing race in status unit test

* Adding EE race tests

* Fixing race in cluster info

* Removing code that's isn't needed

* Fixing some more races

* Fixing govet issue

2 files changed, 6 insertions, 12 deletions

diff --git a/app/email_test.go b/app/email_test.go
index 17b892585..6d1a6f14a 100644
--- a/app/email_test.go
+++ b/app/email_test.go
@@ -61,7 +61,6 @@ func TestSendChangeUsernameEmail(t *testing.T) {
 
 func TestSendEmailChangeVerifyEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var userId string = "5349853498543jdfvndf9834"
 	var newUserEmail string = "newtest@example.com"
@@ -113,7 +112,6 @@ func TestSendEmailChangeVerifyEmail(t *testing.T) {
 
 func TestSendEmailChangeEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var oldEmail string = "test@example.com"
 	var newUserEmail string = "newtest@example.com"
@@ -161,7 +159,6 @@ func TestSendEmailChangeEmail(t *testing.T) {
 
 func TestSendVerifyEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var userId string = "5349853498543jdfvndf9834"
 	var userEmail string = "test@example.com"
@@ -213,7 +210,6 @@ func TestSendVerifyEmail(t *testing.T) {
 
 func TestSendSignInChangeEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var email string = "test@example.com"
 	var locale string = "en"
@@ -261,7 +257,6 @@ func TestSendSignInChangeEmail(t *testing.T) {
 
 func TestSendWelcomeEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var userId string = "32432nkjnijn432uj32"
 	var email string = "test@example.com"
@@ -355,7 +350,6 @@ func TestSendWelcomeEmail(t *testing.T) {
 
 func TestSendPasswordChangeEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var email string = "test@example.com"
 	var locale string = "en"
@@ -403,7 +397,6 @@ func TestSendPasswordChangeEmail(t *testing.T) {
 
 func TestSendMfaChangeEmail(t *testing.T) {
 	Setup()
-	utils.LoadConfig("config.json")
 
 	var email string = "test@example.com"
 	var locale string = "en"
@@ -488,7 +481,6 @@ func TestSendMfaChangeEmail(t *testing.T) {
 
 func TestSendInviteEmails(t *testing.T) {
 	th := Setup().InitBasic()
-	utils.LoadConfig("config.json")
 
 	var email1 string = "test1@example.com"
 	var email2 string = "test2@example.com"
@@ -564,7 +556,6 @@ func TestSendInviteEmails(t *testing.T) {
 
 func TestSendPasswordReset(t *testing.T) {
 	th := Setup().InitBasic()
-	utils.LoadConfig("config.json")
 
 	var siteURL string = "http://test.mattermost.io"
 	// var locale string = "en"
diff --git a/app/web_hub.go b/app/web_hub.go
index a0663459a..f65683f70 100644
--- a/app/web_hub.go
+++ b/app/web_hub.go
@@ -8,6 +8,7 @@ import (
 	"hash/fnv"
 	"runtime"
 	"runtime/debug"
+	"sync/atomic"
 
 	l4g "github.com/alecthomas/log4go"
 
@@ -18,6 +19,7 @@ import (
 
 type Hub struct {
 	connections    []*WebConn
+	count          int64
 	register       chan *WebConn
 	unregister     chan *WebConn
 	broadcast      chan *model.WebSocketEvent
@@ -43,12 +45,12 @@ func NewWebHub() *Hub {
 func TotalWebsocketConnections() int {
 	// This is racy, but it's only used for reporting information
 	// so it's probably OK
-	count := 0
+	count := int64(0)
 	for _, hub := range hubs {
-		count = count + len(hub.connections)
+		count = count + atomic.LoadInt64(&hub.count)
 	}
 
-	return count
+	return int(count)
 }
 
 func HubStart() {
@@ -248,6 +250,7 @@ func (h *Hub) Start() {
 			select {
 			case webCon := <-h.register:
 				h.connections = append(h.connections, webCon)
+				atomic.StoreInt64(&h.count, int64(len(h.connections)))
 
 			case webCon := <-h.unregister:
 				userId := webCon.UserId