重写了ping示例，现在它是一个实用的工具了

cmd/mcping/README.md

@@ -0,0 +1,5 @@
+# mcping
+适用于Minecraft: Java Edition的ping工具
+
+Useage:
+    `mcping <hostname>[:port]`

cmd/mcping/mcping.go

@@ -0,0 +1,89 @@
+// Useage: go run cmd/ping/ping.go localhost
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/Tnze/go-mc/bot"
+	"github.com/Tnze/go-mc/chat"
+	uuid "github.com/satori/go.uuid"
+)
+
+type status struct {
+	Description chat.Message
+	Players     struct {
+		Max    int
+		Online int
+		Sample []struct {
+			ID   uuid.UUID
+			Name string
+		}
+	}
+	Version struct {
+		Name     string
+		Protocol int
+	}
+	//favicon ignored
+}
+
+func main() {
+	addr, port := getAddr()
+
+	fmt.Printf("MCPING (%s:%d):\n", addr, port)
+
+	resp, delay, err := bot.PingAndList(addr, port)
+	if err != nil {
+		fmt.Printf("ping and list server fail: %v", err)
+		os.Exit(1)
+	}
+
+	var s status
+	err = json.Unmarshal(resp, &s)
+	if err != nil {
+		fmt.Print("unmarshal resp fail:", err)
+		os.Exit(1)
+	}
+
+	fmt.Print(s)
+	fmt.Println("Delay:", delay)
+}
+
+func getAddr() (string, int) {
+	const useage = "Useage: mcping <hostname>[:port]"
+	if len(os.Args) < 2 {
+		fmt.Println("no host name.", useage)
+		os.Exit(1)
+	}
+
+	addr := strings.Split(os.Args[1], ":")
+	var port int
+	switch len(addr) {
+	case 1:
+		port = 25565
+	case 2:
+		var err error
+		port, err = strconv.Atoi(addr[1])
+		if err != nil {
+			fmt.Println(err, useage)
+			os.Exit(1)
+		}
+	}
+
+	return addr[0], port
+}
+
+func (s status) String() string {
+	var sb strings.Builder
+	fmt.Fprintln(&sb, "Server:", s.Version.Name)
+	fmt.Fprintln(&sb, "Protocol:", s.Version.Protocol)
+	fmt.Fprintln(&sb, "Description:", s.Description)
+	fmt.Fprintf(&sb, "Players: %d/%d\n", s.Players.Online, s.Players.Max)
+	for _, v := range s.Players.Sample {
+		fmt.Fprintf(&sb, "- [%s] %v\n", v.Name, v.ID)
+	}
+	return sb.String()
+}

cmd/ping/ping.go

@@ -1,21 +0,0 @@
-// Useage: go run cmd/ping/ping.go localhost
-package main
-
-import (
-	"log"
-	"os"
-
-	"github.com/Tnze/go-mc/bot"
-)
-
-func main() {
-	if len(os.Args) < 2 {
-		log.Fatalln("no host name. Useage: ping [hostname]")
-	}
-
-	resp, delay, err := bot.PingAndList(os.Args[1], 25565)
-	if err != nil {
-		log.Fatalf("ping and list server fail: %v", err)
-	}
-	log.Println("Status:"+string(resp), "\nDealy:", delay)
-}

go.mod

@@ -2,4 +2,8 @@ module github.com/Tnze/go-mc
 
 go 1.12
 
-require github.com/satori/go.uuid v1.2.0
+require (
+	github.com/kr/pretty v0.1.0 // indirect
+	github.com/satori/go.uuid v1.2.0
+	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
+)

go.sum

@@ -1,2 +1,9 @@
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/satori/go.uuid v1.2.0 h1:0uYX9dsZ2yD7q2RtLRtPSdGDWzjeM3TbMJP9utgA0ww=
 github.com/satori/go.uuid v1.2.0/go.mod h1:dA0hQrYB0VpLJoorglMZABFdXlWrHn1NEOzdhQKdks0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=