feat(web): add logging middleware and refactor handlers

Introduced LoggerMiddleware for HTTP request logging. Refactored handler
methods to return http.HandlerFunc for improved composability. Updated
route registration and tests to use new handler signatures.

internal/web/handlers.go

@@ -9,7 +9,8 @@ import (
 	"github.com/rjNemo/payit/internal/payments"
 )
 
-func (h *Handler) createCheckoutSession(w http.ResponseWriter, r *http.Request) {
+func (h *Handler) createCheckoutSession() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
 		var req payments.CheckoutSessionRequest
 
 		if r.Body != nil {
@@ -44,3 +45,4 @@ func (h *Handler) createCheckoutSession(w http.ResponseWriter, r *http.Request)
 			return
 		}
 	}
+}

internal/web/handlers_test.go

@@ -37,7 +37,7 @@ func TestCreateCheckoutSessionSuccess(t *testing.T) {
 	req := httptest.NewRequest(http.MethodPost, "/api/checkout", bytes.NewReader(body))
 	rec := httptest.NewRecorder()
 
-	handler.createCheckoutSession(rec, req)
+	handler.createCheckoutSession()(rec, req)
 
 	if rec.Code != http.StatusOK {
 		t.Fatalf("expected status 200, got %d", rec.Code)
@@ -70,7 +70,7 @@ func TestCreateCheckoutSessionDefaultsQuantity(t *testing.T) {
 	req := httptest.NewRequest(http.MethodPost, "/api/checkout", http.NoBody)
 	rec := httptest.NewRecorder()
 
-	handler.createCheckoutSession(rec, req)
+	handler.createCheckoutSession()(rec, req)
 
 	if rec.Code != http.StatusOK {
 		t.Fatalf("expected status 200, got %d", rec.Code)
@@ -86,7 +86,7 @@ func TestCreateCheckoutSessionRejectsInvalidJSON(t *testing.T) {
 	req := httptest.NewRequest(http.MethodPost, "/api/checkout", bytes.NewBufferString("{"))
 	rec := httptest.NewRecorder()
 
-	handler.createCheckoutSession(rec, req)
+	handler.createCheckoutSession()(rec, req)
 
 	if rec.Code != http.StatusBadRequest {
 		t.Fatalf("expected status 400, got %d", rec.Code)
@@ -101,7 +101,7 @@ func TestCreateCheckoutSessionStripeFailure(t *testing.T) {
 	req := httptest.NewRequest(http.MethodPost, "/api/checkout", http.NoBody)
 	rec := httptest.NewRecorder()
 
-	handler.createCheckoutSession(rec, req)
+	handler.createCheckoutSession()(rec, req)
 
 	if rec.Code != http.StatusInternalServerError {
 		t.Fatalf("expected status 500, got %d", rec.Code)
@@ -111,7 +111,7 @@ func TestCreateCheckoutSessionStripeFailure(t *testing.T) {
 func TestCreateCheckoutSessionMethodNotAllowed(t *testing.T) {
 	handler := &Handler{checkout: &fakeCheckoutService{}}
 	mux := http.NewServeMux()
-	mux.HandleFunc("POST /api/checkout", handler.createCheckoutSession)
+	mux.HandleFunc("POST /api/checkout", handler.createCheckoutSession())
 
 	req := httptest.NewRequest(http.MethodGet, "/api/checkout", http.NoBody)
 	rec := httptest.NewRecorder()

internal/web/middleware.go

@@ -0,0 +1,26 @@
+package web
+
+import (
+	"log"
+	"net/http"
+	"time"
+)
+
+type WrappedWriter struct {
+	http.ResponseWriter
+	StatusCode int
+}
+
+func (w *WrappedWriter) WriteHeader(statusCode int) {
+	w.StatusCode = statusCode
+	w.ResponseWriter.WriteHeader(statusCode)
+}
+
+func LoggerMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		wrapped := &WrappedWriter{ResponseWriter: w, StatusCode: http.StatusOK}
+		next.ServeHTTP(wrapped, r)
+		log.Printf("%s %s %d %v", r.Method, r.URL.Path, wrapped.StatusCode, time.Since(start))
+	})
+}

internal/web/page.go

@@ -13,7 +13,8 @@ type checkoutPageData struct {
 	Currency           string
 }
 
-func (h *Handler) renderCheckoutPage(w http.ResponseWriter, r *http.Request) {
+func (h *Handler) renderCheckoutPage() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
 		price := float64(h.cfg.Product.PriceCents) / 100
 		data := checkoutPageData{
 			ProductName:        h.cfg.Product.Name,
@@ -28,3 +29,4 @@ func (h *Handler) renderCheckoutPage(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 	}
+}

internal/web/routes.go

@@ -5,7 +5,7 @@ import (
 )
 
 func (h *Handler) registerRoutes(mux *http.ServeMux) {
-	mux.HandleFunc("POST /api/checkout", h.createCheckoutSession)
+	mux.Handle("POST /api/checkout", h.createCheckoutSession())
-	mux.Handle("GET /", http.HandlerFunc(h.renderCheckoutPage))
+	mux.Handle("GET /", h.renderCheckoutPage())
 	mux.Handle("GET /static/", http.StripPrefix("/static/", http.FileServer(http.FS(h.fs))))
 }

internal/web/server.go

@@ -41,5 +41,5 @@ func NewServer(cfg config.Config) http.Handler {
 	mux := http.NewServeMux()
 	h.registerRoutes(mux)
 
-	return mux
+	return LoggerMiddleware(mux)
 }