separated logger middleware

internal/server/middleware/log.go

@@ -0,0 +1,81 @@
+package middleware
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"time"
+
+	"ruben/inventory2/internal/server/response"
+)
+
+func LogRequests(ctx context.Context, logger *slog.Logger) response.Middleware {
+	reqIDCh := newRequestIDProvider(ctx)
+
+	return func(fn response.HandlerFunc) response.HandlerFunc {
+		return func(r *http.Request) (response.Response, error) {
+			start := time.Now()
+
+			args := []any{
+				"id", <-reqIDCh,
+				"url", r.URL,
+			}
+
+			logger.Debug("Request", args...)
+
+			res, err := fn(r)
+			end := time.Now()
+
+			var status int
+			if err != nil {
+				status = response.GetStatusFromError(err)
+			} else {
+				var ok bool
+				if status, ok = res.GetStatus(); !ok {
+					status = http.StatusOK
+				}
+			}
+
+			args = append(args,
+				"status", status,
+				"elapsed", time.Duration(end.UnixNano()-start.UnixNano()),
+			)
+
+			switch status / 100 {
+			case 1:
+				logger.Debug("Response", args...)
+			case 2:
+				logger.Debug("Response", args...)
+			case 3:
+				logger.Debug("Response", args...)
+			case 4:
+				logger.Warn("Response", args...)
+			default:
+				logger.Error("Response", args...)
+			}
+
+			return res, err
+		}
+	}
+}
+
+func newRequestIDProvider(ctx context.Context) <-chan int {
+	reqIDCh := make(chan int)
+
+	go func() {
+		defer close(reqIDCh)
+
+		nextReqID := 1
+
+		for {
+			select {
+			case reqIDCh <- nextReqID:
+				nextReqID += 1
+			case <-ctx.Done():
+				return
+			}
+		}
+	}()
+
+	return reqIDCh
+}