Files
go-mc/server/ping.go
2021-12-15 15:07:39 +08:00

149 lines
3.4 KiB
Go

package server
import (
"encoding/base64"
"encoding/json"
"errors"
"github.com/Tnze/go-mc/chat"
"github.com/Tnze/go-mc/data/packetid"
"github.com/Tnze/go-mc/net"
pk "github.com/Tnze/go-mc/net/packet"
"github.com/google/uuid"
"image"
"image/png"
"strings"
)
// ListPingHandler collect server running status info
// which is used to handle client ping and list progress.
type ListPingHandler interface {
// Name of the server version
Name() string
// Protocol number
Protocol() int
MaxPlayer() int
OnlinePlayer() int
// PlayerSamples is a short list of some player in the server
PlayerSamples() []PlayerSample
Description() *chat.Message
// FavIcon should be a PNG image that is Base64 encoded
// (without newlines: \n, new lines no longer work since 1.13)
// and prepended with "data:image/png;base64,".
//
// This method can return empty string if no icon is set.
FavIcon() string
}
type PlayerSample struct {
Name string `json:"name"`
ID uuid.UUID `json:"id"`
}
func (s *Server) acceptListPing(conn *net.Conn) {
var p pk.Packet
for i := 0; i < 2; i++ { // Ping or List. Only allow check twice
err := conn.ReadPacket(&p)
if err != nil {
return
}
switch p.ID {
case packetid.StatusResponse: //List
var resp []byte
resp, err = s.listResp()
if err != nil {
break
}
err = conn.WritePacket(pk.Marshal(0x00, pk.String(resp)))
case packetid.StatusPongResponse: //Ping
err = conn.WritePacket(p)
}
if err != nil {
return
}
}
}
func (s *Server) listResp() ([]byte, error) {
var list struct {
Version struct {
Name string `json:"name"`
Protocol int `json:"protocol"`
} `json:"version"`
Players struct {
Max int `json:"max"`
Online int `json:"online"`
Sample []PlayerSample `json:"sample"`
} `json:"players"`
Description *chat.Message `json:"description"`
FavIcon string `json:"favicon,omitempty"`
}
list.Version.Name = s.Name()
list.Version.Protocol = s.Protocol()
list.Players.Max = s.MaxPlayer()
list.Players.Online = s.OnlinePlayer()
list.Players.Sample = s.PlayerSamples()
list.Description = s.Description()
list.FavIcon = s.FavIcon()
return json.Marshal(list)
}
// PingInfo implement ListPingHandler.
type PingInfo struct {
name string
protocol int
*PlayerList
description chat.Message
favicon string
}
// NewPingInfo crate a new PingInfo, the icon can be nil.
func NewPingInfo(list *PlayerList, name string, protocol int, motd chat.Message, icon image.Image) (p *PingInfo, err error) {
var favIcon string
if icon != nil {
if !icon.Bounds().Size().Eq(image.Point{X: 64, Y: 64}) {
return nil, errors.New("icon size is not 64x64")
}
// Encode icon into string "data:image/png;base64,......" format
var sb strings.Builder
sb.WriteString("data:image/png;base64,")
w := base64.NewEncoder(base64.StdEncoding, &sb)
err = png.Encode(w, icon)
if err != nil {
return nil, err
}
err = w.Close()
if err != nil {
return nil, err
}
favIcon = sb.String()
}
p = &PingInfo{
name: name,
protocol: protocol,
PlayerList: list,
description: motd,
favicon: favIcon,
}
return
}
func (p *PingInfo) Name() string {
return p.name
}
func (p *PingInfo) Protocol() int {
return p.protocol
}
func (p *PingInfo) FavIcon() string {
return p.favicon
}
func (p *PingInfo) Description() *chat.Message {
return &p.description
}