eb_peer_http_getter.go

package gossipcache

import (
	"bytes"
	"context"
	"fmt"
	pb "github.com/golang/groupcache/groupcachepb"
	"github.com/golang/protobuf/proto"
	"io"
	"net/http"
	"net/url"
)

type ProtoGetter interface {
	Get(ctx context.Context, in *pb.GetRequest, out *pb.GetResponse) error
}

type httpGetter struct {
	baseURL string
}

func (h *httpGetter) Get(ctx context.Context, in *pb.GetRequest, out *pb.GetResponse) error {
	u := fmt.Sprintf("%v%v/%v", h.baseURL, url.QueryEscape(in.GetGroup()), url.QueryEscape(in.GetKey()))
	req, err := http.NewRequest("GET", u, nil)
	if err != nil {
		return err
	}
	req = req.WithContext(ctx)
	tr := http.DefaultTransport
	res, err := tr.RoundTrip(req)

	if err != nil {
		return err
	}
	defer res.Body.Close()
	if res.StatusCode != http.StatusOK {
		return fmt.Errorf("server returned: %v", res.Status)
	}
	b := new(bytes.Buffer)
	_, err = io.Copy(b, res.Body)
	if err != nil {
		return fmt.Errorf("reading response body: %v", err)
	}
	err = proto.Unmarshal(b.Bytes(), out)
	if err != nil {
		return fmt.Errorf("decoding response body: %v", err)
	}
	return nil
}