feat: add json definition and method to trace info

- its preparation for upcoming debug log formatter

request.go

@@ -1276,7 +1276,7 @@ func (r *Request) TraceInfo() TraceInfo {
 
 	// Capture remote address info when connection is non-nil
 	if ct.gotConnInfo.Conn != nil {
-		ti.RemoteAddr = ct.gotConnInfo.Conn.RemoteAddr()
+		ti.RemoteAddr = ct.gotConnInfo.Conn.RemoteAddr().String()
 	}
 
 	return ti

request_test.go

@@ -1803,7 +1803,9 @@ func TestTraceInfo(t *testing.T) {
 			assertEqual(t, true, tr.TotalTime >= 0)
 			assertEqual(t, true, tr.TotalTime < time.Hour)
 			assertEqual(t, true, tr.TotalTime == resp.Time())
-			assertEqual(t, tr.RemoteAddr.String(), serverAddr)
+			assertEqual(t, tr.RemoteAddr, serverAddr)
+
+			assertNotNil(t, tr.Clone())
 		}
 
 		client.DisableTrace()
@@ -1823,7 +1825,7 @@ func TestTraceInfo(t *testing.T) {
 			assertEqual(t, true, tr.ResponseTime >= 0)
 			assertEqual(t, true, tr.TotalTime >= 0)
 			assertEqual(t, true, tr.TotalTime == resp.Time())
-			assertEqual(t, tr.RemoteAddr.String(), serverAddr)
+			assertEqual(t, tr.RemoteAddr, serverAddr)
 		}
 
 	})
@@ -1837,6 +1839,9 @@ func TestTraceInfo(t *testing.T) {
 			resp, err := c.R().EnableTrace().EnableDebug().Get(u)
 			assertNil(t, err)
 			assertNotNil(t, resp)
+
+			jsonStr := resp.Request.TraceInfo().JSON()
+			assertEqual(t, true, strings.Contains(jsonStr, serverAddr))
 		}
 
 		logContent := logBuf.String()

trace.go

@@ -9,7 +9,6 @@ import (
 	"context"
 	"crypto/tls"
 	"fmt"
-	"net"
 	"net/http/httptrace"
 	"time"
 )
@@ -19,45 +18,45 @@ import (
 type TraceInfo struct {
 	// DNSLookup is the duration that transport took to perform
 	// DNS lookup.
-	DNSLookup time.Duration
+	DNSLookup time.Duration `json:"dns_lookup_time"`
 
 	// ConnTime is the duration it took to obtain a successful connection.
-	ConnTime time.Duration
+	ConnTime time.Duration `json:"connection_time"`
 
 	// TCPConnTime is the duration it took to obtain the TCP connection.
-	TCPConnTime time.Duration
+	TCPConnTime time.Duration `json:"tcp_connection_time"`
 
 	// TLSHandshake is the duration of the TLS handshake.
-	TLSHandshake time.Duration
+	TLSHandshake time.Duration `json:"tls_handshake_time"`
 
 	// ServerTime is the server's duration for responding to the first byte.
-	ServerTime time.Duration
+	ServerTime time.Duration `json:"server_time"`
 
 	// ResponseTime is the duration since the first response byte from the server to
 	// request completion.
-	ResponseTime time.Duration
+	ResponseTime time.Duration `json:"response_time"`
 
 	// TotalTime is the duration of the total time request taken end-to-end.
-	TotalTime time.Duration
+	TotalTime time.Duration `json:"total_time"`
 
 	// IsConnReused is whether this connection has been previously
 	// used for another HTTP request.
-	IsConnReused bool
+	IsConnReused bool `json:"is_connection_reused"`
 
 	// IsConnWasIdle is whether this connection was obtained from an
 	// idle pool.
-	IsConnWasIdle bool
+	IsConnWasIdle bool `json:"is_connection_was_idle"`
 
 	// ConnIdleTime is the duration how long the connection that was previously
 	// idle, if IsConnWasIdle is true.
-	ConnIdleTime time.Duration
+	ConnIdleTime time.Duration `json:"connection_idle_time"`
 
 	// RequestAttempt is to represent the request attempt made during a Resty
 	// request execution flow, including retry count.
-	RequestAttempt int
+	RequestAttempt int `json:"request_attempt"`
 
 	// RemoteAddr returns the remote network address.
-	RemoteAddr net.Addr
+	RemoteAddr string `json:"remote_address"`
 }
 
 // String method returns string representation of request trace information.
@@ -80,6 +79,21 @@ func (ti TraceInfo) String() string {
 		ti.RemoteAddr)
 }
 
+// JSON method returns the JSON string of request trace information
+func (ti TraceInfo) JSON() string {
+	buf := acquireBuffer()
+	defer releaseBuffer(buf)
+	_ = encodeJSON(buf, ti)
+	return buf.String()
+}
+
+// Clone method returns the clone copy of [TraceInfo]
+func (ti TraceInfo) Clone() *TraceInfo {
+	ti2 := new(TraceInfo)
+	*ti2 = ti
+	return ti2
+}
+
 // clientTrace struct maps the [httptrace.ClientTrace] hooks into Fields
 // with the same naming for easy understanding. Plus additional insights
 // [Request].