PlayerInfo functionality

a2sPlayerRequest.go

@@ -0,0 +1,22 @@
+package steam
+
+import (
+	"bytes"
+
+	"github.com/golang/glog"
+)
+
+type A2SPlayerRequest struct {
+	c ChallengeResponse
+}
+
+func (a A2SPlayerRequest) MarshalBinary() []byte {
+	buf := new(bytes.Buffer)
+
+	writeRequestPrefix(buf)
+	writeByte(buf, 'U')
+	buf.Write(a.c.GetChallange())
+
+	glog.V(2).Infof("steam: a2SPlayerRequest buffer: %v", buf.Bytes())
+	return buf.Bytes()
+}

a2sPlayerResponse.go

@@ -0,0 +1,56 @@
+package steam
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+
+	"github.com/golang/glog"
+)
+
+type Player struct {
+	index    byte
+	name     string
+	score    int32
+	duration float32
+}
+
+type A2SPlayersResponse struct {
+	playersCount byte
+	players      []Player
+}
+
+func (a *A2SPlayersResponse) UnMarshalBinary(data []byte) (err error) {
+	glog.V(2).Infof("steam: unmarshalling binary for A2SPlayersResponse: %v", data)
+	buf := bytes.NewBuffer(data)
+
+	if header := readByte(buf); header != 0x44 {
+		return errors.New("steam: invalid header in the a2splayersresponse")
+	}
+
+	a.playersCount = readByte(buf)
+	a.players = make([]Player, a.playersCount)
+
+	for i := 0; i < int(a.playersCount); i++ {
+		p := &a.players[i]
+		p.index = readByte(buf)
+		p.name = readString(buf)
+		p.score = readLong(buf)
+		p.duration = readFloat(buf)
+	}
+
+	return nil
+}
+
+func (a *A2SPlayersResponse) String() string {
+	buf := new(bytes.Buffer)
+
+	writeString(buf, fmt.Sprintf("players count: %v\n\n", a.playersCount))
+	for _, player := range a.players {
+		writeString(buf, fmt.Sprintf("player index: %v\n", player.index))
+		writeString(buf, fmt.Sprintf("player name: %v\n", player.name))
+		writeString(buf, fmt.Sprintf("player score: %v\n", player.score))
+		writeString(buf, fmt.Sprintf("player duration: %v seconds\n\n", player.duration))
+	}
+	return buf.String()
+}

challengeRequest.go

@@ -0,0 +1,21 @@
+package steam
+
+import (
+	"bytes"
+
+	"github.com/golang/glog"
+)
+
+type ChallengeRequest struct {
+}
+
+func (ChallengeRequest) MarshalBinary() []byte {
+	buf := new(bytes.Buffer)
+
+	writeRequestPrefix(buf)
+	writeByte(buf, 'U')
+	writeRequestPrefix(buf)
+
+	glog.V(2).Infof("steam: challengeRequest buffer: %v", buf.Bytes())
+	return buf.Bytes()
+}

challengeResponse.go

@@ -0,0 +1,28 @@
+package steam
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/golang/glog"
+)
+
+type ChallengeResponse []byte
+
+func (c ChallengeResponse) GetChallange() (challenge []byte) {
+	glog.V(2).Infof("steam: getting challenge from %v", c)
+
+	return c[(len(c) - 4):]
+}
+
+func (c ChallengeResponse) String() string {
+	buf := new(bytes.Buffer)
+
+	writeString(buf, fmt.Sprint("challengeResponse: ["))
+	for i := 0; i < len(c); i++ {
+		writeString(buf, fmt.Sprintf("%x ", c[i]))
+	}
+	writeString(buf, fmt.Sprint("]"))
+
+	return buf.String()
+}

comm.go

@@ -16,6 +16,7 @@ const (
 type ServerType int
 
 func (st *ServerType) UnmarshalBinary(data []byte) error {
+	glog.V(3).Infof("steam: unmarshalling binary %v for server type ", data)
 	switch data[0] {
 	case 'd':
 		*st = STDedicated
@@ -51,6 +52,7 @@ var serverTypeStrings = map[ServerType]string{
 type Environment int
 
 func (e *Environment) UnmarshalBinary(data []byte) error {
+	glog.V(3).Infof("steam: unmarshalling binary %v for env ", data)
 	switch data[0] {
 	case 'l':
 		*e = ELinux
@@ -86,6 +88,7 @@ var environmentStrings = map[Environment]string{
 type Visibility int
 
 func (v *Visibility) UnmarshalBinary(data []byte) error {
+	glog.V(3).Infof("steam: unmarshalling binary %v for visibility ", data)
 	switch data[0] {
 	case 0:
 		*v = VPublic
@@ -155,6 +158,7 @@ func (InfoRequest) MarshalBinary() ([]byte, error) {
 	writeByte(buf, 'T')
 	writeString(buf, "Source Engine Query")
 
+	glog.V(3).Infof("steam: marshaled binary. buffer: %v", buf)
 	return buf.Bytes(), nil
 }
 
@@ -193,6 +197,7 @@ const (
 )
 
 func (r *InfoResponse) UnmarshalBinary(data []byte) (err error) {
+	glog.V(3).Infof("steam: unmarshalling binary %v", data)
 	defer func() {
 		if e := recover(); e != nil {
 			err = e.(parseError)

samples/sample.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 
 	"github.com/kidoman/go-steam"
@@ -15,13 +16,17 @@ var addresses = []string{
 }
 
 func main() {
+	flag.Parse()
 	for _, address := range addresses {
 		server := &steam.Server{Addr: address}
 		ping, err := server.Ping()
 		must(err)
 		info, err := server.Info()
 		must(err)
+		playerInfo, err := server.PLayerInfo()
+		must(err)
 		fmt.Printf("%v: %v with ping %v\n", address, info, ping)
+		fmt.Printf("players info: %v\n", playerInfo)
 	}
 }
 

server.go

@@ -3,6 +3,8 @@ package steam
 import (
 	"errors"
 	"time"
+
+	"github.com/golang/glog"
 )
 
 // Server represents a Source server.
@@ -53,6 +55,7 @@ func (s *Server) Ping() (time.Duration, error) {
 		return 0, err
 	}
 
+	glog.V(3).Infof("steam: sending data %v via socket in ping", data)
 	start := time.Now()
 	s.socket.send(data)
 	if _, err := s.socket.receive(); err != nil {
@@ -74,10 +77,7 @@ func (s *Server) Info() (*InfoResponse, error) {
 		return nil, err
 	}
 
-	if err := s.socket.send(data); err != nil {
-		return nil, err
-	}
-	b, err := s.socket.receive()
+	b, err := s.sendAndRecieve(data)
 	if err != nil {
 		return nil, err
 	}
@@ -89,3 +89,47 @@ func (s *Server) Info() (*InfoResponse, error) {
 
 	return res, nil
 }
+
+// PlayerInfo retrieves players information on the server.
+func (s *Server) PLayerInfo() (*A2SPlayersResponse, error) {
+	if err := s.init(); err != nil {
+		return nil, err
+	}
+
+	data := ChallengeRequest{}.MarshalBinary()
+
+	b, err := s.sendAndRecieve(data)
+	if err != nil {
+		return nil, err
+	}
+
+	challengeRes := ChallengeResponse(b)
+	data = A2SPlayerRequest{challengeRes}.MarshalBinary()
+
+	b, err = s.sendAndRecieve(data)
+	if err != nil {
+		return nil, err
+	}
+
+	a2sPlayerRes := new(A2SPlayersResponse)
+
+	if err := a2sPlayerRes.UnMarshalBinary(b); err != nil {
+		return nil, err
+	}
+
+	return a2sPlayerRes, nil
+}
+
+func (s *Server) sendAndRecieve(data []byte) ([]byte, error) {
+	glog.V(3).Infof("steam: sending data %v via socket in info", data)
+	if err := s.socket.send(data); err != nil {
+		return nil, err
+	}
+
+	b, err := s.socket.receive()
+	if err != nil {
+		return nil, err
+	}
+	glog.V(3).Infof("steam: received data %v via socket", b)
+	return b, nil
+}

socket.go

@@ -3,6 +3,8 @@ package steam
 import (
 	"errors"
 	"net"
+
+	"github.com/golang/glog"
 )
 
 type socket struct {
@@ -29,6 +31,7 @@ func (s *socket) close() {
 }
 
 func (s *socket) send(payload []byte) error {
+	glog.V(3).Infof("steam: writing %v to UDP", payload)
 	n, err := s.conn.WriteToUDP(payload, s.raddr)
 	if err != nil {
 		return err

wire.go

@@ -94,6 +94,22 @@ func readLongLong(buf *bytes.Buffer) int64 {
 	return int64(t[0] + t[1]<<8 + t[2]<<16 + t[3]<<24 + t[4]<<32 + t[5]<<40 + t[6]<<48 + t[7]<<56)
 }
 
+func readLong(buf *bytes.Buffer) int32 {
+	var t [4]byte
+	n, err := buf.Read(t[:])
+	if err != nil {
+		triggerError(errCouldNotReadData)
+	}
+	if n != 4 {
+		triggerError(errNotEnoughDataInResponse)
+	}
+	return int32(t[0] + t[1]<<8 + t[2]<<16 + t[3]<<24)
+}
+
+func readFloat(buf *bytes.Buffer) float32 {
+	return float32(readLong(buf))
+}
+
 func readString(buf *bytes.Buffer) string {
 	bytes, err := buf.ReadBytes(0)
 	if err != nil {