chore: import upstream snapshot with attribution

codec/protorpc/protorpc.go

@@ -0,0 +1,186 @@
+// Protorpc provides a net/rpc proto-rpc codec. See envelope.proto for the format.
+package protorpc
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"strconv"
+	"sync"
+
+	"github.com/golang/protobuf/proto"
+	"go-micro.dev/v6/codec"
+)
+
+type flusher interface {
+	Flush() error
+}
+
+type protoCodec struct {
+	rwc io.ReadWriteCloser
+	buf *bytes.Buffer
+	mt  codec.MessageType
+	sync.Mutex
+}
+
+func (c *protoCodec) Close() error {
+	c.buf.Reset()
+	return c.rwc.Close()
+}
+
+func (c *protoCodec) String() string {
+	return "proto-rpc"
+}
+
+func id(id string) uint64 {
+	p, err := strconv.ParseInt(id, 10, 64)
+	if err != nil {
+		p = 0
+	}
+	i := uint64(p)
+	return i
+}
+
+func (c *protoCodec) Write(m *codec.Message, b interface{}) error {
+	switch m.Type {
+	case codec.Request:
+		c.Lock()
+		defer c.Unlock()
+		// This is protobuf, of course we copy it.
+		pbr := &Request{ServiceMethod: m.Method, Seq: id(m.Id)}
+		data, err := proto.Marshal(pbr)
+		if err != nil {
+			return err
+		}
+		_, err = WriteNetString(c.rwc, data)
+		if err != nil {
+			return err
+		}
+		// dont trust or incoming message
+		m, ok := b.(proto.Message)
+		if !ok {
+			return codec.ErrInvalidMessage
+		}
+		data, err = proto.Marshal(m)
+		if err != nil {
+			return err
+		}
+		_, err = WriteNetString(c.rwc, data)
+		if err != nil {
+			return err
+		}
+		if flusher, ok := c.rwc.(flusher); ok {
+			if err = flusher.Flush(); err != nil {
+				return err
+			}
+		}
+	case codec.Response, codec.Error:
+		c.Lock()
+		defer c.Unlock()
+		rtmp := &Response{ServiceMethod: m.Method, Seq: id(m.Id), Error: m.Error}
+		data, err := proto.Marshal(rtmp)
+		if err != nil {
+			return err
+		}
+		_, err = WriteNetString(c.rwc, data)
+		if err != nil {
+			return err
+		}
+		if pb, ok := b.(proto.Message); ok {
+			data, err = proto.Marshal(pb)
+			if err != nil {
+				return err
+			}
+		} else {
+			data = nil
+		}
+		_, err = WriteNetString(c.rwc, data)
+		if err != nil {
+			return err
+		}
+		if flusher, ok := c.rwc.(flusher); ok {
+			if err = flusher.Flush(); err != nil {
+				return err
+			}
+		}
+	case codec.Event:
+		m, ok := b.(proto.Message)
+		if !ok {
+			return codec.ErrInvalidMessage
+		}
+		data, err := proto.Marshal(m)
+		if err != nil {
+			return err
+		}
+		_, _ = c.rwc.Write(data)
+	default:
+		return fmt.Errorf("unrecognized message type: %v", m.Type)
+	}
+	return nil
+}
+
+func (c *protoCodec) ReadHeader(m *codec.Message, mt codec.MessageType) error {
+	c.buf.Reset()
+	c.mt = mt
+
+	switch mt {
+	case codec.Request:
+		data, err := ReadNetString(c.rwc)
+		if err != nil {
+			return err
+		}
+		rtmp := new(Request)
+		err = proto.Unmarshal(data, rtmp)
+		if err != nil {
+			return err
+		}
+		m.Method = rtmp.GetServiceMethod()
+		m.Id = fmt.Sprintf("%d", rtmp.GetSeq())
+	case codec.Response:
+		data, err := ReadNetString(c.rwc)
+		if err != nil {
+			return err
+		}
+		rtmp := new(Response)
+		err = proto.Unmarshal(data, rtmp)
+		if err != nil {
+			return err
+		}
+		m.Method = rtmp.GetServiceMethod()
+		m.Id = fmt.Sprintf("%d", rtmp.GetSeq())
+		m.Error = rtmp.GetError()
+	case codec.Event:
+		_, err := io.Copy(c.buf, c.rwc)
+		return err
+	default:
+		return fmt.Errorf("unrecognized message type: %v", mt)
+	}
+	return nil
+}
+
+func (c *protoCodec) ReadBody(b interface{}) error {
+	var data []byte
+	switch c.mt {
+	case codec.Request, codec.Response:
+		var err error
+		data, err = ReadNetString(c.rwc)
+		if err != nil {
+			return err
+		}
+	case codec.Event:
+		data = c.buf.Bytes()
+	default:
+		return fmt.Errorf("unrecognized message type: %v", c.mt)
+	}
+	if b != nil {
+		return proto.Unmarshal(data, b.(proto.Message))
+	}
+	return nil
+}
+
+func NewCodec(rwc io.ReadWriteCloser) codec.Codec {
+	return &protoCodec{
+		buf: bytes.NewBuffer(nil),
+		rwc: rwc,
+	}
+}