feat: backend core - auth, user, role, permission, device, webhook, monitoring, cache, repository, service, middleware, API handlers

internal/monitoring/exposure_test.go

@@ -0,0 +1,47 @@
+package monitoring_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+
+	"github.com/user-management-system/internal/monitoring"
+)
+
+func TestPrometheusHandlerForRegistryExposesBusinessMetrics(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	metrics := monitoring.NewMetrics()
+	router := gin.New()
+	router.Use(monitoring.PrometheusMiddleware(metrics))
+	router.GET("/ready", func(c *gin.Context) {
+		c.Status(http.StatusNoContent)
+	})
+	router.GET("/metrics", gin.WrapH(promhttp.HandlerFor(metrics.GetRegistry(), promhttp.HandlerOpts{})))
+
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest(http.MethodGet, "/ready", nil)
+	router.ServeHTTP(recorder, request)
+	if recorder.Code != http.StatusNoContent {
+		t.Fatalf("expected 204, got %d", recorder.Code)
+	}
+
+	metricsRecorder := httptest.NewRecorder()
+	metricsRequest := httptest.NewRequest(http.MethodGet, "/metrics", nil)
+	router.ServeHTTP(metricsRecorder, metricsRequest)
+	if metricsRecorder.Code != http.StatusOK {
+		t.Fatalf("expected metrics endpoint to return 200, got %d", metricsRecorder.Code)
+	}
+
+	body := metricsRecorder.Body.String()
+	if !strings.Contains(body, `http_requests_total{method="GET",path="/ready",status="204"} 1`) {
+		t.Fatalf("expected recorded request metric in body, got %s", body)
+	}
+	if !strings.Contains(body, `http_request_duration_seconds_bucket{method="GET",path="/ready"`) {
+		t.Fatalf("expected recorded request duration metric in body, got %s", body)
+	}
+}