fix memberList inconsistent output (#11812)

* etcdctl/ctlv3: support to print memberlist in hex format json

* e2e: add memberListWithHexTest

* CHANGELOG: update for #11812

etcdctl/ctlv3/command/printer.go

@@ -78,7 +78,7 @@ func NewPrinter(printerType string, isHex bool) printer {
 	case "fields":
 		return &fieldsPrinter{newPrinterUnsupported("fields")}
 	case "json":
-		return newJSONPrinter()
+		return newJSONPrinter(isHex)
 	case "protobuf":
 		return newPBPrinter()
 	case "table":

etcdctl/ctlv3/command/printer_json.go

@@ -15,18 +15,25 @@
 package command
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"os"
+	"strconv"
 
+	"go.etcd.io/etcd/v3/clientv3"
 	"go.etcd.io/etcd/v3/clientv3/snapshot"
 )
 
-type jsonPrinter struct{ printer }
+type jsonPrinter struct {
+	isHex bool
+	printer
+}
 
-func newJSONPrinter() printer {
+func newJSONPrinter(isHex bool) printer {
 	return &jsonPrinter{
-		&printerRPC{newPrinterUnsupported("json"), printJSON},
+		isHex:   isHex,
+		printer: &printerRPC{newPrinterUnsupported("json"), printJSON},
 	}
 }
 
@@ -35,6 +42,14 @@ func (p *jsonPrinter) EndpointStatus(r []epStatus) { printJSON(r) }
 func (p *jsonPrinter) EndpointHashKV(r []epHashKV) { printJSON(r) }
 func (p *jsonPrinter) DBStatus(r snapshot.Status)  { printJSON(r) }
 
+func (p *jsonPrinter) MemberList(r clientv3.MemberListResponse) {
+	if p.isHex {
+		printMemberListWithHexJSON(r)
+	} else {
+		printJSON(r)
+	}
+}
+
 func printJSON(v interface{}) {
 	b, err := json.Marshal(v)
 	if err != nil {
@@ -43,3 +58,46 @@ func printJSON(v interface{}) {
 	}
 	fmt.Println(string(b))
 }
+
+func printMemberListWithHexJSON(r clientv3.MemberListResponse) {
+	var buffer bytes.Buffer
+	var b []byte
+	buffer.WriteString("{\"header\":{\"cluster_id\":\"")
+	b = strconv.AppendUint(nil, r.Header.ClusterId, 16)
+	buffer.Write(b)
+	buffer.WriteString("\",\"member_id\":\"")
+	b = strconv.AppendUint(nil, r.Header.MemberId, 16)
+	buffer.Write(b)
+	buffer.WriteString("\",\"raft_term\":")
+	b = strconv.AppendUint(nil, r.Header.RaftTerm, 16)
+	buffer.Write(b)
+	buffer.WriteByte('}')
+	for i := 0; i < len(r.Members); i++ {
+		if i == 0 {
+			buffer.WriteString(",\"members\":[{\"ID\":\"")
+		} else {
+			buffer.WriteString(",{\"ID\":\"")
+		}
+		b = strconv.AppendUint(nil, r.Members[i].ID, 16)
+		buffer.Write(b)
+		buffer.WriteString("\",\"name\":\"" + r.Members[i].Name + "\"," + "\"peerURLs\":")
+		b, err := json.Marshal(r.Members[i].PeerURLs)
+		if err != nil {
+			return
+		}
+		buffer.Write(b)
+		buffer.WriteString(",\"clientURLS\":")
+		b, err = json.Marshal(r.Members[i].ClientURLs)
+		if err != nil {
+			return
+		}
+		buffer.Write(b)
+		buffer.WriteByte('}')
+		if i == len(r.Members)-1 {
+			buffer.WriteString("]")
+		}
+	}
+	buffer.WriteString("}")
+	fmt.Println(string(buffer.Bytes()))
+
+}