Merge pull request #10 from mcstatus-io/v4

Merge v4 into main

Author: PassTheMayo

cmd/main.go

@@ -21,6 +21,7 @@ type passedOptions struct {
 	Type       string `short:"t" long:"type" description:"The type of status to retrieve" default:"java"`
 	Timeout    uint   `short:"T" long:"timeout" description:"The amount of seconds before the status retrieval times out" default:"5"`
 	DisableSRV bool   `short:"S" long:"disable-srv" description:"Disables SRV lookup"`
+	Debug      bool   `short:"D" long:"debug" description:"Enables debug printing to the console"`
 }
 
 func init() {
@@ -62,6 +63,8 @@ func main() {
 				EnableSRV:       !opts.DisableSRV,
 				Timeout:         time.Duration(opts.Timeout) * time.Second,
 				ProtocolVersion: 47,
+				Ping:            true,
+				Debug:           opts.Debug,
 			})
 
 			break

options/status.go

@@ -10,6 +10,7 @@ type StatusModern struct {
 	Timeout         time.Duration
 	ProtocolVersion int
 	Ping            bool
+	Debug           bool
 }
 
 // StatusLegacy is the options used by the status.Legacy() function.

status/modern.go

@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"log"
 	"math/rand"
 	"net"
 	"time"
@@ -21,8 +22,9 @@ import (
 var defaultJavaStatusOptions = options.StatusModern{
 	EnableSRV:       true,
 	Timeout:         time.Second * 5,
-	ProtocolVersion: 47,
+	ProtocolVersion: -1,
 	Ping:            true,
+	Debug:           false,
 }
 
 type rawJavaStatus struct {
@@ -92,19 +94,30 @@ func Modern(ctx context.Context, host string, options ...options.StatusModern) (
 
 func getStatusModern(host string, options ...options.StatusModern) (*response.StatusModern, error) {
 	var (
-		opts                               = parseJavaStatusOptions(options...)
-		connectionPort uint16              = util.DefaultJavaPort
-		srvRecord      *response.SRVRecord = nil
-		rawResponse    rawJavaStatus       = rawJavaStatus{}
-		latency        time.Duration       = 0
+		opts                                   = parseJavaStatusOptions(options...)
+		connectionHostname string              = ""
+		connectionPort     uint16              = util.DefaultJavaPort
+		srvRecord          *response.SRVRecord = nil
+		rawResponse        rawJavaStatus       = rawJavaStatus{}
+		latency            time.Duration       = 0
 	)
 
-	connectionHostname, port, err := util.ParseAddress(host)
+	hostname, port, err := util.ParseAddress(host)
 
 	if err != nil {
 		return nil, err
 	}
 
+	connectionHostname = hostname
+
+	if port != nil {
+		connectionPort = *port
+	}
+
+	if opts.Debug {
+		log.Printf("Parsed address into split hostname and port (host=%s, port=%v, default_port=%d)", connectionHostname, nilValueSwap(port, util.DefaultJavaPort), util.DefaultJavaPort)
+	}
+
 	if opts.EnableSRV && port == nil && net.ParseIP(connectionHostname) == nil {
 		record, err := util.LookupSRV(host)
 
@@ -116,6 +129,12 @@ func getStatusModern(host string, options ...options.StatusModern) (*response.St
 				Host: record.Target,
 				Port: record.Port,
 			}
+
+			if opts.Debug {
+				log.Printf("Found an SRV record (target_host=%s, target_port=%d)", record.Target, record.Port)
+			}
+		} else if opts.Debug {
+			log.Println("Could not find an SRV record for this host")
 		}
 	}
 
@@ -125,37 +144,61 @@ func getStatusModern(host string, options ...options.StatusModern) (*response.St
 		return nil, err
 	}
 
+	if opts.Debug {
+		log.Printf("Successfully connected to %s:%d\n", connectionHostname, connectionPort)
+	}
+
 	defer conn.Close()
 
 	if err = conn.SetDeadline(time.Now().Add(opts.Timeout)); err != nil {
 		return nil, err
 	}
 
-	if err = writeJavaStatusHandshakeRequestPacket(conn, int32(opts.ProtocolVersion), connectionHostname, connectionPort); err != nil {
+	if err = writeJavaStatusHandshakePacket(conn, int32(opts.ProtocolVersion), hostname, nilValueSwap(port, util.DefaultJavaPort)); err != nil {
 		return nil, err
 	}
 
+	if opts.Debug {
+		log.Printf("[S <- C] Wrote handshake packet (proto=%d, host=%s, port=%d, next_state=0)\n", opts.ProtocolVersion, hostname, nilValueSwap(port, util.DefaultJavaPort))
+	}
+
 	if err = writeJavaStatusStatusRequestPacket(conn); err != nil {
 		return nil, err
 	}
 
+	if opts.Debug {
+		log.Println("[S <- C] Wrote status request packet")
+	}
+
 	if err = readJavaStatusStatusResponsePacket(conn, &rawResponse); err != nil {
 		return nil, err
 	}
 
+	if opts.Debug {
+		log.Println("[S -> C] Read status response packet")
+	}
+
 	if opts.Ping {
 		payload := rand.Int63()
 
 		if err = writeJavaStatusPingPacket(conn, payload); err != nil {
 			return nil, err
 		}
 
+		if opts.Debug {
+			log.Printf("[S <- C] Wrote ping packet (payload=%d)\n", payload)
+		}
+
 		pingStart := time.Now()
 
 		if err = readJavaStatusPongPacket(conn, payload); err != nil {
 			return nil, err
 		}
 
+		if opts.Debug {
+			log.Printf("[S -> C] Read ping packet (payload=%d)\n", payload)
+		}
+
 		latency = time.Since(pingStart)
 	}
 
@@ -171,7 +214,7 @@ func parseJavaStatusOptions(opts ...options.StatusModern) options.StatusModern {
 }
 
 // https://wiki.vg/Server_List_Ping#Handshake
-func writeJavaStatusHandshakeRequestPacket(w io.Writer, protocolVersion int32, host string, port uint16) error {
+func writeJavaStatusHandshakePacket(w io.Writer, protocolVersion int32, host string, port uint16) error {
 	buf := &bytes.Buffer{}
 
 	// Packet ID - varint

status/modern_raw.go

@@ -75,7 +75,7 @@ func getStatusRaw(host string, options ...options.StatusModern) (map[string]inte
 		return nil, err
 	}
 
-	if err = writeJavaStatusHandshakeRequestPacket(conn, int32(opts.ProtocolVersion), connectionHostname, connectionPort); err != nil {
+	if err = writeJavaStatusHandshakePacket(conn, int32(opts.ProtocolVersion), connectionHostname, connectionPort); err != nil {
 		return nil, err
 	}
 

status/util.go

@@ -54,3 +54,11 @@ func parsePlayerID(value interface{}) (string, bool) {
 func pointerOf[T any](v T) *T {
 	return &v
 }
+
+func nilValueSwap[T any](a *T, b T) T {
+	if a == nil {
+		return b
+	}
+
+	return *a
+}