feat: add request logger middleware

internal/server/observability.go

@@ -0,0 +1,37 @@
+package server
+
+import (
+	"log"
+	"strconv"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+func RequestLogger() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		start := time.Now()
+		path := c.Request.URL.Path
+		query := c.Request.URL.RawQuery
+
+		c.Next()
+
+		route := c.FullPath()
+		if route == "" {
+			route = path
+		}
+
+		log.Printf(
+			"http_request method=%s route=%s path=%s query=%s status=%d duration_ms=%.2f bytes=%d client_ip=%s errors=%s",
+			c.Request.Method,
+			strconv.Quote(route),
+			strconv.Quote(path),
+			strconv.Quote(query),
+			c.Writer.Status(),
+			float64(time.Since(start).Microseconds())/1000,
+			c.Writer.Size(),
+			strconv.Quote(c.ClientIP()),
+			strconv.Quote(c.Errors.ByType(gin.ErrorTypePrivate).String()),
+		)
+	}
+}