feat(api): add HEAD method for health route (gotenberg#963)

Author: gulien

pkg/modules/api/api.go

@@ -453,13 +453,22 @@ func (a *Api) Start() error {
 		)
 	}
 
-	// Let's not forget the health check route...
+	// Let's not forget the health check routes...
+	checks := append(a.healthChecks, health.WithTimeout(a.timeout))
+	checker := health.NewChecker(checks...)
+	healthCheckHandler := health.NewHandler(checker)
+
 	a.srv.GET(
 		fmt.Sprintf("%s%s", a.rootPath, "health"),
 		func() echo.HandlerFunc {
-			checks := append(a.healthChecks, health.WithTimeout(a.timeout))
-			checker := health.NewChecker(checks...)
-			return echo.WrapHandler(health.NewHandler(checker))
+			return echo.WrapHandler(healthCheckHandler)
+		}(),
+		hardTimeoutMiddleware(hardTimeout),
+	)
+	a.srv.HEAD(
+		fmt.Sprintf("%s%s", a.rootPath, "health"),
+		func() echo.HandlerFunc {
+			return echo.WrapHandler(healthCheckHandler)
 		}(),
 		hardTimeoutMiddleware(hardTimeout),
 	)

pkg/modules/api/api_test.go

@@ -839,18 +839,23 @@ func TestApi_Start(t *testing.T) {
 				return
 			}
 
-			// health request.
+			// health requests.
 			recorder := httptest.NewRecorder()
-			healthRequest := httptest.NewRequest(http.MethodGet, "/health", nil)
 
-			mod.srv.ServeHTTP(recorder, healthRequest)
+			healthGetRequest := httptest.NewRequest(http.MethodGet, "/health", nil)
+			mod.srv.ServeHTTP(recorder, healthGetRequest)
+			if recorder.Code != http.StatusOK {
+				t.Errorf("expected %d status code but got %d", http.StatusOK, recorder.Code)
+			}
+
+			healthHeadRequest := httptest.NewRequest(http.MethodHead, "/health", nil)
+			mod.srv.ServeHTTP(recorder, healthHeadRequest)
 			if recorder.Code != http.StatusOK {
 				t.Errorf("expected %d status code but got %d", http.StatusOK, recorder.Code)
 			}
 
 			// version request.
 			versionRequest := httptest.NewRequest(http.MethodGet, "/version", nil)
-
 			mod.srv.ServeHTTP(recorder, versionRequest)
 			if recorder.Code != http.StatusOK {
 				t.Errorf("expected %d status code but got %d", http.StatusOK, recorder.Code)
@@ -859,7 +864,6 @@ func TestApi_Start(t *testing.T) {
 			// "multipart/form-data" request.
 			multipartRequest := func(url string) *http.Request {
 				body := &bytes.Buffer{}
-
 				writer := multipart.NewWriter(body)
 
 				defer func() {