feat(middleware): add request tracing and logging middleware

- Add RequestTracingMiddleware for comprehensive HTTP request logging
- Log request ID, timestamp, method, path, user info, duration, status code
- Generate and propagate unique request IDs for tracing
- Structured JSON logging for easy parsing and analysis
- Capture request body, headers, query params, and user context

internal/middleware/request_tracing.go

@@ -0,0 +1,122 @@
+package middleware
+
+import (
+	"bookmann/internal/config"
+	"bytes"
+	"encoding/json"
+	"io"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/labstack/echo/v4"
+)
+
+type responseWriter struct {
+	http.ResponseWriter
+	size int
+}
+
+func (r *responseWriter) Write(b []byte) (int, error) {
+	size, err := r.ResponseWriter.Write(b)
+	r.size += size
+	return size, err
+}
+
+type RequestLogEntry struct {
+	RequestID    string            `json:"request_id"`
+	Timestamp    time.Time         `json:"timestamp"`
+	Method       string            `json:"method"`
+	Path         string            `json:"path"`
+	QueryParams  map[string]string `json:"query_params,omitempty"`
+	Headers      map[string]string `json:"headers,omitempty"`
+	Body         interface{}       `json:"body,omitempty"`
+	UserID       string            `json:"user_id,omitempty"`
+	UserRole     string            `json:"user_role,omitempty"`
+	UserEmail    string            `json:"user_email,omitempty"`
+	RemoteAddr   string            `json:"remote_addr"`
+	UserAgent    string            `json:"user_agent,omitempty"`
+	Duration     time.Duration     `json:"duration"`
+	StatusCode   int               `json:"status_code"`
+	ResponseSize int64             `json:"response_size"`
+	Error        string            `json:"error,omitempty"`
+}
+
+func RequestTracingMiddleware(cfg *config.Config) echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			start := time.Now()
+
+			requestID := c.Response().Header().Get(echo.HeaderXRequestID)
+			if requestID == "" {
+				requestID = uuid.New().String()
+				c.Response().Header().Set(echo.HeaderXRequestID, requestID)
+			}
+
+			recorder := &responseWriter{
+				ResponseWriter: c.Response().Writer,
+			}
+			c.Response().Writer = recorder
+
+			var body interface{}
+			if c.Request().Body != nil && c.Request().Method != "GET" {
+				bodyBytes, _ := io.ReadAll(c.Request().Body)
+				c.Request().Body = io.NopCloser(bytes.NewBuffer(bodyBytes))
+
+				if len(bodyBytes) > 0 && len(bodyBytes) < 10000 {
+					json.Unmarshal(bodyBytes, &body)
+				}
+			}
+
+			headers := make(map[string]string)
+			for k, v := range c.Request().Header {
+				if len(v) > 0 {
+					headers[k] = v[0]
+				}
+			}
+
+			userID, _ := c.Get("user_id").(string)
+			userRole, _ := c.Get("user_role").(string)
+			userEmail, _ := c.Get("user_email").(string)
+
+			err := next(c)
+
+			duration := time.Since(start)
+
+			queryParams := make(map[string]string)
+			for k, v := range c.QueryParams() {
+				if len(v) > 0 {
+					queryParams[k] = v[0]
+				}
+			}
+
+			logEntry := RequestLogEntry{
+				RequestID:    requestID,
+				Timestamp:    start,
+				Method:       c.Request().Method,
+				Path:         c.Request().URL.Path,
+				QueryParams:  queryParams,
+				Headers:      headers,
+				Body:         body,
+				UserID:       userID,
+				UserRole:     userRole,
+				UserEmail:    userEmail,
+				RemoteAddr:   c.RealIP(),
+				UserAgent:    c.Request().UserAgent(),
+				Duration:     duration,
+				StatusCode:   c.Response().Status,
+				ResponseSize: int64(recorder.size),
+			}
+
+			if err != nil {
+				logEntry.Error = err.Error()
+			}
+
+			logJSON, _ := json.Marshal(logEntry)
+			log.Printf("[REQUEST] %s", string(logJSON))
+
+			return err
+		}
+	}
+}