micro/server/rpc_codec.go
2019-01-14 21:30:43 +00:00

212 lines
4.2 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
}
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 {
// the initieal message
m := codec.Message{
Header: c.req.Header,
Body: c.req.Body,
}
// 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
// set the message body
m.Body = tm.Body
// set req
c.req = &tm
}
// no longer first read
c.first = false
// set some internal things
m.Target = m.Header["X-Micro-Service"]
m.Endpoint = m.Header["X-Micro-Endpoint"]
m.Id = m.Header["X-Micro-Id"]
// read header via codec
err := c.codec.ReadHeader(&m, codec.Request)
// set the method/id
r.Endpoint = m.Endpoint
r.Id = m.Id
return err
}
func (c *rpcCodec) ReadBody(b interface{}) error {
// don't read empty body
if len(c.req.Body) == 0 {
return nil
}
return c.codec.ReadBody(b)
}
func (c *rpcCodec) Write(r *codec.Message, b interface{}) error {
c.buf.wbuf.Reset()
// create a new message
m := &codec.Message{
Endpoint: r.Endpoint,
Id: r.Id,
Error: r.Error,
Type: r.Type,
Header: r.Header,
}
if m.Header == nil {
m.Header = map[string]string{}
}
// set request id
if len(r.Id) > 0 {
m.Header["X-Micro-Id"] = r.Id
}
// set target
if len(r.Target) > 0 {
m.Header["X-Micro-Service"] = r.Target
}
// set request endpoint
if len(r.Endpoint) > 0 {
m.Header["X-Micro-Endpoint"] = r.Endpoint
}
if len(r.Error) > 0 {
m.Header["X-Micro-Error"] = r.Error
}
// the body being sent
var body []byte
// if we have encoded data just send it
if len(r.Body) > 0 {
body = r.Body
// write the body to codec
} else if err := c.codec.Write(m, b); 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
// no body to write
if err := c.codec.Write(m, nil); err != nil {
return err
}
// write the body
} else {
// set the body
body = c.buf.wbuf.Bytes()
}
// Set content type if theres content
if len(body) > 0 {
m.Header["Content-Type"] = c.req.Header["Content-Type"]
}
// send on the socket
return c.socket.Send(&transport.Message{
Header: m.Header,
Body: body,
})
}
func (c *rpcCodec) Close() error {
c.buf.Close()
c.codec.Close()
return c.socket.Close()
}
func (c *rpcCodec) String() string {
return "rpc"
}