Add allowed burst for requests to rate limiting middleware

main.go

@@ -61,7 +61,7 @@ func main() {
 	pipes := pipelines.LoadPipelines()
 
 	authMiddleware := middlewares.CreateAuthenticationMiddleware(appSettings.Token)
-	rateLimiterMiddleware, err := middlewares.CreateRateLimiterMiddleware(appSettings.RequestsPerMinute)
+	rateLimiterMiddleware, err := middlewares.CreateRateLimiterMiddleware(appSettings.RequestsPerMinute, 0)
 	if err != nil {
 		panic(err)
 	}

middlewares/ratelimiter.go

@@ -15,7 +15,7 @@ func (middleware RateLimiterMiddleware) Middleware(next http.Handler) http.Handl
 	return middleware.rateLimiter.RateLimit(next)
 }
 
-func CreateRateLimiterMiddleware(requestsPerMinute int) (*RateLimiterMiddleware, error) {
+func CreateRateLimiterMiddleware(requestsPerMinute int, allowedBurst int) (*RateLimiterMiddleware, error) {
 	store, err := memstore.New(65536)
 
 	if err != nil {
@@ -23,7 +23,8 @@ func CreateRateLimiterMiddleware(requestsPerMinute int) (*RateLimiterMiddleware,
 	}
 
 	quota := throttled.RateQuota{
-		MaxRate: throttled.PerMin(requestsPerMinute),
+		MaxRate:  throttled.PerMin(requestsPerMinute),
+		MaxBurst: allowedBurst,
 	}
 
 	rateLimiter, err := throttled.NewGCRARateLimiter(store, quota)

middlewares/ratelimiter_test.go

@@ -8,41 +8,57 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func ExecuteRequest(middlewareHandler http.Handler) int {
+	request, _ := http.NewRequest("GET", "/", nil)
+	responseRecorder := httptest.NewRecorder()
+
+	middlewareHandler.ServeHTTP(responseRecorder, request)
+
+	return responseRecorder.Code
+}
+
 func TestRateLimiterMiddleware(t *testing.T) {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 	})
 
 	t.Run("AuthorizationMiddleware returns 200 response when rate limit is not hit", func(t *testing.T) {
-		middleware, err := CreateRateLimiterMiddleware(1)
+		middleware, err := CreateRateLimiterMiddleware(1, 0)
 		assert.Nil(t, err)
 
 		middlewareHandler := middleware.Middleware(handler)
 
-		request, _ := http.NewRequest("GET", "/", nil)
-		responseRecorder := httptest.NewRecorder()
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+	})
 
-		middlewareHandler.ServeHTTP(responseRecorder, request)
+	t.Run("AuthorizationMiddleware returns 429 response when rate limit is hit", func(t *testing.T) {
+		middleware, err := CreateRateLimiterMiddleware(1, 0)
+		assert.Nil(t, err)
 
-		assert.Equal(t, 200, responseRecorder.Code)
+		middlewareHandler := middleware.Middleware(handler)
+
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+		assert.Equal(t, 429, ExecuteRequest(middlewareHandler))
 	})
 
-	t.Run("AuthorizationMiddleware returns 429 response when rate limit is hit", func(t *testing.T) {
-		middleware, err := CreateRateLimiterMiddleware(1)
+	t.Run("AuthorizationMiddleware returns 200 response when rate limit with burst is not hit", func(t *testing.T) {
+		middleware, err := CreateRateLimiterMiddleware(1, 1)
 		assert.Nil(t, err)
 
 		middlewareHandler := middleware.Middleware(handler)
 
-		request, _ := http.NewRequest("GET", "/", nil)
-		responseRecorder := httptest.NewRecorder()
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+	})
 
-		middlewareHandler.ServeHTTP(responseRecorder, request)
-		assert.Equal(t, 200, responseRecorder.Code)
+	t.Run("AuthorizationMiddleware returns 429 response when rate limit with burst is hit", func(t *testing.T) {
+		middleware, err := CreateRateLimiterMiddleware(1, 1)
+		assert.Nil(t, err)
 
-		request, _ = http.NewRequest("GET", "/", nil)
-		responseRecorder = httptest.NewRecorder()
+		middlewareHandler := middleware.Middleware(handler)
 
-		middlewareHandler.ServeHTTP(responseRecorder, request)
-		assert.Equal(t, 429, responseRecorder.Code)
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+		assert.Equal(t, 200, ExecuteRequest(middlewareHandler))
+		assert.Equal(t, 429, ExecuteRequest(middlewareHandler))
 	})
 }