added test files

cmd/app/handler/httpjson/handler.go

@@ -31,16 +31,6 @@ func New(logger *zap.Logger) (*echo.Echo, Handler) {
 
 // RunServer runs http server and listens until context is canceled.
 func (h *Handler) RunServer(ctx context.Context, conf *config.Config, e *echo.Echo) error {
-	go func() {
-		<-ctx.Done()
-
-		timeout, cancel := context.WithTimeout(context.Background(), time.Duration(conf.API.ReadTimeout)*time.Second)
-		defer cancel()
-
-		_ = e.Shutdown(timeout) // try gracefully first
-		_ = e.Close()           // immediate termination
-	}()
-
 	server := &http.Server{
 		Addr:         fmt.Sprintf(":%d", conf.API.Port),
 		ReadTimeout:  time.Duration(conf.API.ReadTimeout) * time.Second,
@@ -48,7 +38,18 @@ func (h *Handler) RunServer(ctx context.Context, conf *config.Config, e *echo.Ec
 		IdleTimeout:  time.Duration(conf.API.IdleTimeout) * time.Second,
 	}
 
-	if err := e.StartServer(server); !errors.Is(err, http.ErrServerClosed) {
+	go func() {
+		<-ctx.Done()
+
+		shutdownCtx, cancel := context.WithTimeout(context.Background(), time.Duration(conf.API.ReadTimeout)*time.Second)
+		defer cancel()
+
+		if err := server.Shutdown(shutdownCtx); err != nil {
+			h.logger.Warn("graceful shutdown failed", zap.Error(err))
+		}
+	}()
+
+	if err := e.StartServer(server); err != nil && !errors.Is(err, http.ErrServerClosed) {
 		return errors.Wrap(err, "server error")
 	}
 

cmd/app/handler/httpjson/handler_test.go

@@ -0,0 +1,87 @@
+package httpjson
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/kjannette/go_http_server/internal/config"
+	"github.com/labstack/echo/v4"
+	"go.uber.org/zap"
+)
+
+func TestRunServer_ShutdownOnCancel(t *testing.T) {
+	e, h := New(zap.NewNop())
+
+	cfg := &config.Config{}
+	cfg.API.Port = 0
+	cfg.API.ReadTimeout = 2
+	cfg.API.WriteTimeout = 2
+	cfg.API.IdleTimeout = 2
+
+	ctx, cancel := context.WithCancel(context.Background())
+
+	errCh := make(chan error, 1)
+	go func() {
+		errCh <- h.RunServer(ctx, cfg, e)
+	}()
+
+	healthURL, err := waitForHealthURL(e, 3*time.Second)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	client := &http.Client{Transport: &http.Transport{DisableKeepAlives: true}}
+	resp, err := client.Get(healthURL)
+	if err != nil {
+		t.Fatalf("GET /health: %v", err)
+	}
+	body, err := io.ReadAll(resp.Body)
+	_ = resp.Body.Close()
+	if err != nil {
+		t.Fatalf("read body: %v", err)
+	}
+	if resp.StatusCode != http.StatusOK || string(body) != "OK" {
+		t.Fatalf("health check: status=%d body=%q", resp.StatusCode, body)
+	}
+
+	cancel()
+
+	select {
+	case err := <-errCh:
+		if err != nil {
+			t.Fatalf("RunServer() error = %v", err)
+		}
+	case <-time.After(10 * time.Second):
+		t.Fatal("RunServer did not exit after context cancel")
+	}
+}
+
+func waitForHealthURL(e *echo.Echo, timeout time.Duration) (string, error) {
+	client := &http.Client{Transport: &http.Transport{DisableKeepAlives: true}}
+	deadline := time.Now().Add(timeout)
+	for time.Now().Before(deadline) {
+		if e.Listener != nil {
+			_, port, err := net.SplitHostPort(e.Listener.Addr().String())
+			if err != nil {
+				return "", fmt.Errorf("split listener addr: %w", err)
+			}
+			url := fmt.Sprintf("http://127.0.0.1:%s/health", port)
+
+			resp, err := client.Get(url)
+			if err == nil {
+				_, _ = io.Copy(io.Discard, resp.Body)
+				_ = resp.Body.Close()
+				if resp.StatusCode == http.StatusOK {
+					return url, nil
+				}
+			}
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+	return "", fmt.Errorf("server not ready within %s", timeout)
+}

cmd/app/handler/httpjson/health_test.go

@@ -0,0 +1,35 @@
+package httpjson
+
+import (
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"go.uber.org/zap"
+)
+
+func TestHealthCheck(t *testing.T) {
+	e, _ := New(zap.NewNop())
+
+	req := httptest.NewRequest(http.MethodGet, "/health", nil)
+	rec := httptest.NewRecorder()
+
+	e.ServeHTTP(rec, req)
+
+	if rec.Code != http.StatusOK {
+		t.Errorf("status = %d, want %d", rec.Code, http.StatusOK)
+	}
+
+	body, err := io.ReadAll(rec.Body)
+	if err != nil {
+		t.Fatalf("read body: %v", err)
+	}
+	if string(body) != "OK" {
+		t.Errorf("body = %q, want %q", body, "OK")
+	}
+
+	if ct := rec.Header().Get("Content-Type"); ct != "text/plain; charset=UTF-8" {
+		t.Errorf("Content-Type = %q, want text/plain; charset=UTF-8", ct)
+	}
+}