add a new websocket2 package without breaking changes to the iris API. It implements the gobwas/ws library (it works but need fixes on determinate closing connections) as suggested at: https://github.com/kataras/iris/issues/1178

Former-commit-id: be5ee623b7d030bd9e03a1a2f320ead975ef2ba8

websocket2/message.go

@@ -0,0 +1,182 @@
+package websocket
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/json"
+	"strconv"
+
+	"github.com/kataras/iris/core/errors"
+	"github.com/valyala/bytebufferpool"
+)
+
+type (
+	messageType uint8
+)
+
+func (m messageType) String() string {
+	return strconv.Itoa(int(m))
+}
+
+func (m messageType) Name() string {
+	switch m {
+	case messageTypeString:
+		return "string"
+	case messageTypeInt:
+		return "int"
+	case messageTypeBool:
+		return "bool"
+	case messageTypeBytes:
+		return "[]byte"
+	case messageTypeJSON:
+		return "json"
+	default:
+		return "Invalid(" + m.String() + ")"
+	}
+}
+
+// The same values are exists on client side too.
+const (
+	messageTypeString messageType = iota
+	messageTypeInt
+	messageTypeBool
+	messageTypeBytes
+	messageTypeJSON
+)
+
+const (
+	messageSeparator = ";"
+)
+
+var messageSeparatorByte = messageSeparator[0]
+
+type messageSerializer struct {
+	prefix []byte
+
+	prefixLen       int
+	separatorLen    int
+	prefixAndSepIdx int
+	prefixIdx       int
+	separatorIdx    int
+
+	buf *bytebufferpool.Pool
+}
+
+func newMessageSerializer(messagePrefix []byte) *messageSerializer {
+	return &messageSerializer{
+		prefix:          messagePrefix,
+		prefixLen:       len(messagePrefix),
+		separatorLen:    len(messageSeparator),
+		prefixAndSepIdx: len(messagePrefix) + len(messageSeparator) - 1,
+		prefixIdx:       len(messagePrefix) - 1,
+		separatorIdx:    len(messageSeparator) - 1,
+
+		buf: new(bytebufferpool.Pool),
+	}
+}
+
+var (
+	boolTrueB  = []byte("true")
+	boolFalseB = []byte("false")
+)
+
+// websocketMessageSerialize serializes a custom websocket message from websocketServer to be delivered to the client
+// returns the string form of the message
+// Supported data types are: string, int, bool, bytes and JSON.
+func (ms *messageSerializer) serialize(event string, data interface{}) ([]byte, error) {
+	b := ms.buf.Get()
+	b.Write(ms.prefix)
+	b.WriteString(event)
+	b.WriteByte(messageSeparatorByte)
+
+	switch v := data.(type) {
+	case string:
+		b.WriteString(messageTypeString.String())
+		b.WriteByte(messageSeparatorByte)
+		b.WriteString(v)
+	case int:
+		b.WriteString(messageTypeInt.String())
+		b.WriteByte(messageSeparatorByte)
+		binary.Write(b, binary.LittleEndian, v)
+	case bool:
+		b.WriteString(messageTypeBool.String())
+		b.WriteByte(messageSeparatorByte)
+		if v {
+			b.Write(boolTrueB)
+		} else {
+			b.Write(boolFalseB)
+		}
+	case []byte:
+		b.WriteString(messageTypeBytes.String())
+		b.WriteByte(messageSeparatorByte)
+		b.Write(v)
+	default:
+		//we suppose is json
+		res, err := json.Marshal(data)
+		if err != nil {
+			ms.buf.Put(b)
+			return nil, err
+		}
+		b.WriteString(messageTypeJSON.String())
+		b.WriteByte(messageSeparatorByte)
+		b.Write(res)
+	}
+
+	message := b.Bytes()
+	ms.buf.Put(b)
+
+	return message, nil
+}
+
+var errInvalidTypeMessage = errors.New("Type %s is invalid for message: %s")
+
+// deserialize deserializes a custom websocket message from the client
+// ex: iris-websocket-message;chat;4;themarshaledstringfromajsonstruct will return 'hello' as string
+// Supported data types are: string, int, bool, bytes and JSON.
+func (ms *messageSerializer) deserialize(event []byte, websocketMessage []byte) (interface{}, error) {
+	dataStartIdx := ms.prefixAndSepIdx + len(event) + 3
+	if len(websocketMessage) <= dataStartIdx {
+		return nil, errors.New("websocket invalid message: " + string(websocketMessage))
+	}
+
+	typ, err := strconv.Atoi(string(websocketMessage[ms.prefixAndSepIdx+len(event)+1 : ms.prefixAndSepIdx+len(event)+2])) // in order to iris-websocket-message;user;-> 4
+	if err != nil {
+		return nil, err
+	}
+
+	data := websocketMessage[dataStartIdx:] // in order to iris-websocket-message;user;4; -> themarshaledstringfromajsonstruct
+
+	switch messageType(typ) {
+	case messageTypeString:
+		return string(data), nil
+	case messageTypeInt:
+		msg, err := strconv.Atoi(string(data))
+		if err != nil {
+			return nil, err
+		}
+		return msg, nil
+	case messageTypeBool:
+		if bytes.Equal(data, boolTrueB) {
+			return true, nil
+		}
+		return false, nil
+	case messageTypeBytes:
+		return data, nil
+	case messageTypeJSON:
+		var msg interface{}
+		err := json.Unmarshal(data, &msg)
+		return msg, err
+	default:
+		return nil, errInvalidTypeMessage.Format(messageType(typ).Name(), websocketMessage)
+	}
+}
+
+// getWebsocketCustomEvent return empty string when the websocketMessage is native message
+func (ms *messageSerializer) getWebsocketCustomEvent(websocketMessage []byte) []byte {
+	if len(websocketMessage) < ms.prefixAndSepIdx {
+		return nil
+	}
+	s := websocketMessage[ms.prefixAndSepIdx:]
+	evt := s[:bytes.IndexByte(s, messageSeparatorByte)]
+	return evt
+}