Merge pull request #2278 from fjl/rpc-inproc-pipe

rpc: simplify inproc client
This commit is contained in:
Péter Szilágyi 2016-03-01 14:54:52 +02:00
commit c0bf321ec8
1 changed files with 19 additions and 69 deletions

View File

@ -16,96 +16,46 @@
package rpc
import "encoding/json"
// NewInProcRPCClient creates an in-process buffer stream attachment to a given
// RPC server.
func NewInProcRPCClient(handler *Server) Client {
buffer := &inprocBuffer{
requests: make(chan []byte, 16),
responses: make(chan []byte, 16),
}
client := &inProcClient{
server: handler,
buffer: buffer,
}
go handler.ServeCodec(NewJSONCodec(client.buffer))
return client
}
import (
"encoding/json"
"io"
"net"
)
// inProcClient is an in-process buffer stream attached to an RPC server.
type inProcClient struct {
server *Server
buffer *inprocBuffer
cl io.Closer
enc *json.Encoder
dec *json.Decoder
}
// Close tears down the request channel of the in-proc client.
func (c *inProcClient) Close() {
c.buffer.Close()
c.cl.Close()
}
// NewInProcRPCClient creates an in-process buffer stream attachment to a given
// RPC server.
func NewInProcRPCClient(handler *Server) Client {
p1, p2 := net.Pipe()
go handler.ServeCodec(NewJSONCodec(p1))
return &inProcClient{handler, p2, json.NewEncoder(p2), json.NewDecoder(p2)}
}
// Send marshals a message into a json format and injects in into the client
// request channel.
func (c *inProcClient) Send(msg interface{}) error {
d, err := json.Marshal(msg)
if err != nil {
return err
}
c.buffer.requests <- d
return nil
return c.enc.Encode(msg)
}
// Recv reads a message from the response channel and tries to parse it into the
// given msg interface.
func (c *inProcClient) Recv(msg interface{}) error {
data := <-c.buffer.responses
return json.Unmarshal(data, &msg)
return c.dec.Decode(msg)
}
// Returns the collection of modules the RPC server offers.
func (c *inProcClient) SupportedModules() (map[string]string, error) {
return SupportedModules(c)
}
// inprocBuffer represents the connection between the RPC server and console
type inprocBuffer struct {
readBuf []byte // store remaining request bytes after a partial read
requests chan []byte // list with raw serialized requests
responses chan []byte // list with raw serialized responses
}
// Read will read the next request in json format.
func (b *inprocBuffer) Read(p []byte) (int, error) {
// last read didn't read entire request, return remaining bytes
if len(b.readBuf) > 0 {
n := copy(p, b.readBuf)
if n < len(b.readBuf) {
b.readBuf = b.readBuf[:n]
} else {
b.readBuf = b.readBuf[:0]
}
return n, nil
}
// read next request
req := <-b.requests
n := copy(p, req)
if n < len(req) {
// inprocBuffer too small, store remaining chunk for next read
b.readBuf = req[n:]
}
return n, nil
}
// Write sends the given buffer to the backend.
func (b *inprocBuffer) Write(p []byte) (n int, err error) {
b.responses <- p
return len(p), nil
}
// Close cleans up obtained resources.
func (b *inprocBuffer) Close() error {
close(b.requests)
close(b.responses)
return nil
}