First

client/rpc_client.go

@@ -0,0 +1,157 @@
+package client
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/asim/go-micro/errors"
+	"github.com/asim/go-micro/registry"
+	rpc "github.com/youtube/vitess/go/rpcplus"
+	js "github.com/youtube/vitess/go/rpcplus/jsonrpc"
+	pb "github.com/youtube/vitess/go/rpcplus/pbrpc"
+)
+
+type headerRoundTripper struct {
+	r http.RoundTripper
+}
+
+type RpcClient struct{}
+
+func init() {
+	rand.Seed(time.Now().UnixNano())
+}
+
+func (t *headerRoundTripper) RoundTrip(r *http.Request) (*http.Response, error) {
+	r.Header.Set("X-Client-Version", "1.0")
+	return t.r.RoundTrip(r)
+}
+
+func (r *RpcClient) call(address, path string, request Request, response interface{}) error {
+	pReq := &rpc.Request{
+		ServiceMethod: request.Method(),
+	}
+
+	reqB := bytes.NewBuffer(nil)
+	defer reqB.Reset()
+	buf := &buffer{
+		reqB,
+	}
+
+	var cc rpc.ClientCodec
+	switch request.ContentType() {
+	case "application/octet-stream":
+		cc = pb.NewClientCodec(buf)
+	case "application/json":
+		cc = js.NewClientCodec(buf)
+	default:
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Unsupported request type: %s", request.ContentType()))
+	}
+
+	err := cc.WriteRequest(pReq, request.Request())
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error writing request: %v", err))
+	}
+
+	client := &http.Client{}
+	client.Transport = &headerRoundTripper{http.DefaultTransport}
+
+	request.Headers().Set("Content-Type", request.ContentType())
+
+	hreq := &http.Request{
+		Method: "POST",
+		URL: &url.URL{
+			Scheme: "http",
+			Host:   address,
+			Path:   path,
+		},
+		Header:        request.Headers().(http.Header),
+		Body:          buf,
+		ContentLength: int64(reqB.Len()),
+		Host:          address,
+	}
+
+	rsp, err := client.Do(hreq)
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error sending request: %v", err))
+	}
+	defer rsp.Body.Close()
+
+	b, err := ioutil.ReadAll(rsp.Body)
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error reading response: %v", err))
+	}
+
+	rspB := bytes.NewBuffer(b)
+	defer rspB.Reset()
+	rBuf := &buffer{
+		rspB,
+	}
+
+	switch rsp.Header.Get("Content-Type") {
+	case "application/octet-stream":
+		cc = pb.NewClientCodec(rBuf)
+	case "application/json":
+		cc = js.NewClientCodec(rBuf)
+	default:
+		return errors.InternalServerError("go.micro.client", string(b))
+	}
+
+	pRsp := &rpc.Response{}
+	err = cc.ReadResponseHeader(pRsp)
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error reading response headers: %v", err))
+	}
+
+	if len(pRsp.Error) > 0 {
+		return errors.Parse(pRsp.Error)
+	}
+
+	err = cc.ReadResponseBody(response)
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error reading response body: %v", err))
+	}
+
+	return nil
+}
+
+func (r *RpcClient) CallRemote(address, path string, request Request, response interface{}) error {
+	return r.call(address, path, request, response)
+}
+
+// TODO: Call(..., opts *Options) error {
+func (r *RpcClient) Call(request Request, response interface{}) error {
+	service, err := registry.GetService(request.Service())
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", err.Error())
+	}
+
+	if len(service.Nodes()) == 0 {
+		return errors.NotFound("go.micro.client", "Service not found")
+	}
+
+	n := rand.Int() % len(service.Nodes())
+	node := service.Nodes()[n]
+	address := fmt.Sprintf("%s:%d", node.Address(), node.Port())
+	return r.call(address, "/_rpc", request, response)
+}
+
+func (r *RpcClient) NewRequest(service, method string, request interface{}) *RpcRequest {
+	return r.NewProtoRequest(service, method, request)
+}
+
+func (r *RpcClient) NewProtoRequest(service, method string, request interface{}) *RpcRequest {
+	return newRpcRequest(service, method, request, "application/octet-stream")
+}
+
+func (r *RpcClient) NewJsonRequest(service, method string, request interface{}) *RpcRequest {
+	return newRpcRequest(service, method, request, "application/json")
+}
+
+func NewRpcClient() *RpcClient {
+	return &RpcClient{}
+}