expose MaxGuacMessage & add Parse helper

instruction.go

@@ -39,56 +39,42 @@ func (i *Instruction) Byte() []byte {
 	return []byte(i.String())
 }
 
-// ReadOne takes an instruction from the stream and parses it into an Instruction
-func ReadOne(stream *Stream) (instruction *Instruction, err error) {
-	var instructionBuffer []byte
-
-	// Get instruction
-	instructionBuffer, err = stream.ReadSome()
-
-	// If EOF, return EOF
-	if err != nil {
-		return
-	}
-
-	// Start of element
+func Parse(data []byte) (*Instruction, error) {
 	elementStart := 0
 
 	// Build list of elements
 	elements := make([]string, 0, 1)
-	for elementStart < len(instructionBuffer) {
+	for elementStart < len(data) {
 		// Find end of length
 		lengthEnd := -1
-		for i := elementStart; i < len(instructionBuffer); i++ {
-			if instructionBuffer[i] == '.' {
+		for i := elementStart; i < len(data); i++ {
+			if data[i] == '.' {
 				lengthEnd = i
 				break
 			}
 		}
 		// read() is required to return a complete instruction. If it does
 		// not, this is a severe internal error.
 		if lengthEnd == -1 {
-			err = ErrServer.NewError("ReadSome returned incomplete instruction.")
-			return
+			return nil, ErrServer.NewError("ReadSome returned incomplete instruction.")
 		}
 
 		// Parse length
-		length, e := strconv.Atoi(string(instructionBuffer[elementStart:lengthEnd]))
+		length, e := strconv.Atoi(string(data[elementStart:lengthEnd]))
 		if e != nil {
-			err = ErrServer.NewError("ReadSome returned wrong pattern instruction.", e.Error())
-			return
+			return nil, ErrServer.NewError("ReadSome returned wrong pattern instruction.", e.Error())
 		}
 
 		// Parse element from just after period
 		elementStart = lengthEnd + 1
-		element := string(instructionBuffer[elementStart : elementStart+length])
+		element := string(data[elementStart : elementStart+length])
 
 		// Append element to list of elements
 		elements = append(elements, element)
 
 		// ReadSome terminator after element
 		elementStart += length
-		terminator := instructionBuffer[elementStart]
+		terminator := data[elementStart]
 
 		// Continue reading instructions after terminator
 		elementStart++
@@ -100,10 +86,16 @@ func ReadOne(stream *Stream) (instruction *Instruction, err error) {
 
 	}
 
-	// Pull Opcode off elements list
-	// Create instruction
-	instruction = NewInstruction(elements[0], elements[1:]...)
+	return NewInstruction(elements[0], elements[1:]...), nil
+}
+
+// ReadOne takes an instruction from the stream and parses it into an Instruction
+func ReadOne(stream *Stream) (instruction *Instruction, err error) {
+	var instructionBuffer []byte
+	instructionBuffer, err = stream.ReadSome()
+	if err != nil {
+		return
+	}
 
-	// Return parsed instruction
-	return
+	return Parse(instructionBuffer)
 }

stream.go

@@ -10,7 +10,7 @@ import (
 
 const (
 	SocketTimeout  = 15 * time.Second
-	maxGuacMessage = 8192
+	MaxGuacMessage = 8192
 )
 
 // Stream wraps the connection to Guacamole providing timeouts and reading
@@ -31,7 +31,7 @@ type Stream struct {
 
 // NewStream creates a new stream
 func NewStream(conn net.Conn, timeout time.Duration) (ret *Stream) {
-	buffer := make([]byte, 0, maxGuacMessage*3)
+	buffer := make([]byte, 0, MaxGuacMessage*3)
 	return &Stream{
 		conn:    conn,
 		timeout: timeout,
@@ -128,7 +128,7 @@ func (s *Stream) ReadSome() (instruction []byte, err error) {
 			}
 		}
 
-		if cap(s.buffer) < maxGuacMessage {
+		if cap(s.buffer) < MaxGuacMessage {
 			s.Flush()
 		}
 

ws_server.go

@@ -42,8 +42,8 @@ func NewWebsocketServerWs(connect func(*websocket.Conn, *http.Request) (Tunnel,
 }
 
 const (
-	websocketReadBufferSize  = maxGuacMessage
-	websocketWriteBufferSize = maxGuacMessage * 2
+	websocketReadBufferSize  = MaxGuacMessage
+	websocketWriteBufferSize = MaxGuacMessage * 2
 )
 
 func (s *WebsocketServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
@@ -145,7 +145,7 @@ type MessageWriter interface {
 }
 
 func guacdToWs(ws MessageWriter, guacd InstructionReader) {
-	buf := bytes.NewBuffer(make([]byte, 0, maxGuacMessage*2))
+	buf := bytes.NewBuffer(make([]byte, 0, MaxGuacMessage*2))
 
 	for {
 		ins, err := guacd.ReadSome()
@@ -165,7 +165,7 @@ func guacdToWs(ws MessageWriter, guacd InstructionReader) {
 		}
 
 		// if the buffer has more data in it or we've reached the max buffer size, send the data and reset
-		if !guacd.Available() || buf.Len() >= maxGuacMessage {
+		if !guacd.Available() || buf.Len() >= MaxGuacMessage {
 			if err = ws.WriteMessage(1, buf.Bytes()); err != nil {
 				if err == websocket.ErrCloseSent {
 					return