setup the project structure

internal/middleware/request_logger.go

@@ -0,0 +1,51 @@
+package middleware
+
+import (
+	"time"
+
+	"github.com/labstack/echo/v4"
+	"go.uber.org/zap"
+)
+
+// ZapRequestLogger is a middleware that logs incoming HTTP requests using a zap.Logger.
+// It logs the method, URI, status, latency, remote IP, and response size.
+func ZapRequestLogger(log *zap.Logger) echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			start := time.Now()
+
+			// Run the next handler in the chain
+			err := next(c)
+			if err != nil {
+				// Let Echo's central error handler deal with it
+				c.Error(err)
+			}
+
+			// After the handler has run, we can log the details
+			req := c.Request()
+			res := c.Response()
+			stop := time.Now()
+
+			// These are our structured logging fields
+			fields := []zap.Field{
+				zap.String("method", req.Method),
+				zap.String("uri", req.RequestURI),
+				zap.Int("status", res.Status),
+				zap.String("remote_ip", c.RealIP()),
+				zap.Duration("latency", stop.Sub(start)),
+				zap.Int64("size", res.Size),
+			}
+
+			// Differentiate between server errors and client errors
+			if res.Status >= 500 {
+				log.Error("Server Error", fields...)
+			} else if res.Status >= 400 {
+				log.Warn("Client Error", fields...)
+			} else {
+				log.Info("Request Handled", fields...)
+			}
+
+			return nil
+		}
+	}
+}