Add health and metrics endpoints

main.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"strings"
 	"time"
+	"runtime"
 )
 
 func main() {
@@ -16,6 +17,9 @@ func main() {
 	e.Use(delayImageMiddleware)
 	e.Static("/", "static")
 
+	e.GET("/health", healthHandler)
+	e.GET("/metrics", metricsHandler)
+
 	if os.Getenv("HTTP2") != "" {
 		log.Printf("starting http2 server...")
 		//net/http.Server is a http1.1 server with optional http2 support
@@ -36,3 +40,19 @@ func delayImageMiddleware(next echo.HandlerFunc) echo.HandlerFunc {
 		return next(c)
 	}
 }
+
+func healthHandler(c echo.Context) error {
+	return c.String(http.StatusOK, "OK")
+}
+
+func metricsHandler(c echo.Context) error {
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	metrics := map[string]uint64{
+		"Alloc":      m.Alloc,
+		"TotalAlloc": m.TotalAlloc,
+		"Sys":        m.Sys,
+		"NumGC":      uint64(m.NumGC),
+	}
+	return c.JSON(http.StatusOK, metrics)
+}

main_test.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/labstack/echo"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHealthHandler(t *testing.T) {
+	e := echo.New()
+	req := httptest.NewRequest(http.MethodGet, "/health", nil)
+	rec := httptest.NewRecorder()
+	c := e.NewContext(req, rec)
+
+	if assert.NoError(t, healthHandler(c)) {
+		assert.Equal(t, http.StatusOK, rec.Code)
+		assert.Equal(t, "OK", rec.Body.String())
+	}
+}
+
+func TestMetricsHandler(t *testing.T) {
+	e := echo.New()
+	req := httptest.NewRequest(http.MethodGet, "/metrics", nil)
+	rec := httptest.NewRecorder()
+	c := e.NewContext(req, rec)
+
+	if assert.NoError(t, metricsHandler(c)) {
+		assert.Equal(t, http.StatusOK, rec.Code)
+		assert.Contains(t, rec.Body.String(), "Alloc")
+		assert.Contains(t, rec.Body.String(), "TotalAlloc")
+		assert.Contains(t, rec.Body.String(), "Sys")
+		assert.Contains(t, rec.Body.String(), "NumGC")
+	}
+}