micro/server/rpc_codec.go
2019-01-08 15:38:25 +00:00

172 lines
3.6 KiB
Go

package server
import (
"bytes"
"github.com/micro/go-micro/codec"
raw "github.com/micro/go-micro/codec/bytes"
"github.com/micro/go-micro/codec/grpc"
"github.com/micro/go-micro/codec/json"
"github.com/micro/go-micro/codec/jsonrpc"
"github.com/micro/go-micro/codec/proto"
"github.com/micro/go-micro/codec/protorpc"
"github.com/micro/go-micro/transport"
"github.com/pkg/errors"
)
type rpcCodec struct {
socket transport.Socket
codec codec.Codec
first bool
req *transport.Message
buf *readWriteCloser
}
type readWriteCloser struct {
wbuf *bytes.Buffer
rbuf *bytes.Buffer
}
type serverCodec interface {
ReadHeader(*request, bool) error
ReadBody(interface{}) error
Write(*response, interface{}, bool) error
Close() error
}
var (
DefaultContentType = "application/protobuf"
DefaultCodecs = map[string]codec.NewCodec{
"application/grpc": grpc.NewCodec,
"application/grpc+json": grpc.NewCodec,
"application/grpc+proto": grpc.NewCodec,
"application/json": json.NewCodec,
"application/json-rpc": jsonrpc.NewCodec,
"application/protobuf": proto.NewCodec,
"application/proto-rpc": protorpc.NewCodec,
"application/octet-stream": raw.NewCodec,
}
)
func (rwc *readWriteCloser) Read(p []byte) (n int, err error) {
return rwc.rbuf.Read(p)
}
func (rwc *readWriteCloser) Write(p []byte) (n int, err error) {
return rwc.wbuf.Write(p)
}
func (rwc *readWriteCloser) Close() error {
rwc.rbuf.Reset()
rwc.wbuf.Reset()
return nil
}
func newRpcCodec(req *transport.Message, socket transport.Socket, c codec.NewCodec) codec.Codec {
rwc := &readWriteCloser{
rbuf: bytes.NewBuffer(req.Body),
wbuf: bytes.NewBuffer(nil),
}
r := &rpcCodec{
first: true,
buf: rwc,
codec: c(rwc),
req: req,
socket: socket,
}
return r
}
func (c *rpcCodec) ReadHeader(r *codec.Message, t codec.MessageType) error {
m := codec.Message{Header: c.req.Header}
// if its a follow on request read it
if !c.first {
var tm transport.Message
// read off the socket
if err := c.socket.Recv(&tm); err != nil {
return err
}
// reset the read buffer
c.buf.rbuf.Reset()
// write the body to the buffer
if _, err := c.buf.rbuf.Write(tm.Body); err != nil {
return err
}
// set the message header
m.Header = tm.Header
}
// no longer first read
c.first = false
// set some internal things
m.Target = m.Header["X-Micro-Service"]
m.Method = m.Header["X-Micro-Method"]
m.Id = m.Header["X-Micro-Id"]
// read header via codec
err := c.codec.ReadHeader(&m, codec.Request)
// set the method/id
r.Method = m.Method
r.Id = m.Id
return err
}
func (c *rpcCodec) ReadBody(b interface{}) error {
return c.codec.ReadBody(b)
}
func (c *rpcCodec) Write(r *codec.Message, body interface{}) error {
c.buf.wbuf.Reset()
// create a new message
m := &codec.Message{
Method: r.Method,
Id: r.Id,
Error: r.Error,
Type: r.Type,
Header: map[string]string{
"X-Micro-Id": r.Id,
"X-Micro-Method": r.Method,
"X-Micro-Error": r.Error,
"Content-Type": c.req.Header["Content-Type"],
},
}
// write to the body
if err := c.codec.Write(m, body); err != nil {
c.buf.wbuf.Reset()
// write an error if it failed
m.Error = errors.Wrapf(err, "Unable to encode body").Error()
m.Header["X-Micro-Error"] = m.Error
if err := c.codec.Write(m, nil); err != nil {
return err
}
}
// send on the socket
return c.socket.Send(&transport.Message{
Header: m.Header,
Body: c.buf.wbuf.Bytes(),
})
}
func (c *rpcCodec) Close() error {
c.buf.Close()
c.codec.Close()
return c.socket.Close()
}
func (c *rpcCodec) String() string {
return "rpc"
}