fix: race condition in tests

.github/workflows/go.yml

@@ -19,7 +19,7 @@ jobs:
           go-version: '1.22'
 
       - name: Unit Test
-        run: make unit-tests
+        run: make unit-tests-ci
 
       - name: e2e Test
         run: make ci-e2e

Makefile

@@ -21,9 +21,13 @@ up: ## run all applications in stack
 	docker compose up -d
 
 .PHONY: unit-tests
-unit-tests: ## run unit tests without e2e-tests directory..
+unit-tests: ## run unit tests without e2e-tests directory.
 	go test -race -count=1 `go list ./... | grep -v e2e-tests`
 
+.PHONY: unit-tests-ci
+unit-tests-ci: ## run unit tests without e2e-tests directory (multiple times to find race conditions).
+	go test -race -count=50 -failfast `go list ./... | grep -v e2e-tests`
+
 .PHONY: ci-e2e
 ci-e2e: up
 	go run ./e2e-tests/scripts/wait-ready/main.go -addr=':80;:8081;:8082'
@@ -40,4 +44,4 @@ tests-e2e: ## run end to end tests
 
 
 vendor-licenses: ## report vendor licenses
-	go-licenses report ./cmd/api --template licenses.tpl > licenses.json 2> licenses-errors
+	go-licenses report ./cmd/api --template licenses.tpl > licenses.json 2> licenses-errors

internal/websocket/common/hub_pool_test.go

@@ -54,10 +54,15 @@ func TestCreateRemoveConcurrently(t *testing.T) {
 	hubs := &sync.Map{}
 
 	wg := sync.WaitGroup{}
-	wg.Add(channelsNo * clientsPerChannel)
+	// First we create `channelsNo` goroutines. Each of them creates `clientsPerChannel` sub-goroutines.
+	// This gives us `channelsNo*clientsPerChannel` sub go-routines and `channelsNo` parent goroutines.
+	// Each of them will call `wg.Done() once and we can't progress until all of them are done.
+	wg.Add(channelsNo*clientsPerChannel + channelsNo)
+
 	for i := 0; i < channelsNo; i++ {
 		channelID := fmt.Sprintf("channel-%d", i)
 		go func() {
+			defer wg.Done()
 			for j := 0; j < clientsPerChannel; j++ {
 				c, h := hp.registerClient(channelID, &websocket.Conn{})
 				hubs.Store(h, struct{}{})
@@ -70,7 +75,6 @@ func TestCreateRemoveConcurrently(t *testing.T) {
 			hubs.Store(h, struct{}{})
 		}()
 	}
-
 	wg.Wait()
 
 	for c, hub := range hp.hubs {