Add example programs that sniff the RegistryCodec.nbt

examples/sniffRegistryCodec/daze.go

@@ -0,0 +1,91 @@
+// sniffRegistryCodec is an example that acts as a client,
+// connects to the server and saves its RegistryCodec to a .nbt file.
+package main
+
+import (
+	"flag"
+	"log"
+	"os"
+
+	//"github.com/mattn/go-colorable"
+
+	"github.com/Tnze/go-mc/bot"
+	"github.com/Tnze/go-mc/bot/basic"
+	_ "github.com/Tnze/go-mc/data/lang/zh-cn"
+	"github.com/Tnze/go-mc/data/packetid"
+	"github.com/Tnze/go-mc/nbt"
+	pk "github.com/Tnze/go-mc/net/packet"
+)
+
+var (
+	address = flag.String("address", "127.0.0.1", "The server address")
+	client  *bot.Client
+	player  *basic.Player
+)
+
+func main() {
+	flag.Parse()
+	// log.SetOutput(colorable.NewColorableStdout())
+	client = bot.NewClient()
+	client.Auth.Name = "Daze"
+	player = basic.NewPlayer(client, basic.DefaultSettings, basic.EventsListener{})
+
+	// To receive the raw NBT data, create a new packet handler
+	// instead of just reading player.RegistryCodec in GameStart event.
+	client.Events.AddListener(bot.PacketHandler{
+		ID:       packetid.ClientboundLogin,
+		Priority: 50,
+		F:        onLogin,
+	})
+
+	// Login
+	err := client.JoinServer(*address)
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Println("Login success")
+
+	// JoinGame
+	for {
+		if err = client.HandleGame(); err == nil {
+			panic("HandleGame never return nil")
+		}
+		log.Fatal(err)
+	}
+}
+
+func onLogin(p pk.Packet) error {
+	var DimensionNames []pk.Identifier
+	var RegistryCodec nbt.RawMessage
+	err := p.Scan(
+		new(pk.Int),               // Entity ID
+		new(pk.Boolean),           // Is hardcore
+		new(pk.Byte),              // Gamemode
+		new(pk.Byte),              // Previous Gamemode
+		pk.Array(&DimensionNames), // Dimension Names
+		pk.NBT(&RegistryCodec),    // Registry Codec (Only care about this)
+		// ...Ignored
+	)
+	if err != nil {
+		return err
+	}
+	err = saveToFile("RegistryCodec.nbt", RegistryCodec)
+	if err != nil {
+		return err
+	}
+	log.Print("Successfully written RegistryCodec.nbt")
+	return nil
+}
+
+func saveToFile(filename string, value any) (err error) {
+	f, err := os.Create(filename)
+	if err != nil {
+		return nil
+	}
+	defer func(f *os.File) {
+		if err2 := f.Close(); err == nil {
+			err = err2
+		}
+	}(f)
+	return nbt.NewEncoder(f).Encode(value, "")
+}