etcdserver/api/etcdhttp: use structured logging in peer handler

Signed-off-by: Gyuho Lee <gyuhox@gmail.com>

etcdserver/api/etcdhttp/peer.go

@@ -22,6 +22,8 @@ import (
 	"github.com/coreos/etcd/etcdserver/api"
 	"github.com/coreos/etcd/lease/leasehttp"
 	"github.com/coreos/etcd/rafthttp"
+
+	"go.uber.org/zap"
 )
 
 const (
@@ -29,12 +31,13 @@ const (
 )
 
 // NewPeerHandler generates an http.Handler to handle etcd peer requests.
-func NewPeerHandler(s etcdserver.ServerPeer) http.Handler {
-	return newPeerHandler(s.Cluster(), s.RaftHandler(), s.LeaseHandler())
+func NewPeerHandler(lg *zap.Logger, s etcdserver.ServerPeer) http.Handler {
+	return newPeerHandler(lg, s.Cluster(), s.RaftHandler(), s.LeaseHandler())
 }
 
-func newPeerHandler(cluster api.Cluster, raftHandler http.Handler, leaseHandler http.Handler) http.Handler {
+func newPeerHandler(lg *zap.Logger, cluster api.Cluster, raftHandler http.Handler, leaseHandler http.Handler) http.Handler {
 	mh := &peerMembersHandler{
+		lg:      lg,
 		cluster: cluster,
 	}
 
@@ -52,6 +55,7 @@ func newPeerHandler(cluster api.Cluster, raftHandler http.Handler, leaseHandler
 }
 
 type peerMembersHandler struct {
+	lg      *zap.Logger
 	cluster api.Cluster
 }
 
@@ -68,6 +72,10 @@ func (h *peerMembersHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	ms := h.cluster.Members()
 	w.Header().Set("Content-Type", "application/json")
 	if err := json.NewEncoder(w).Encode(ms); err != nil {
-		plog.Warningf("failed to encode members response (%v)", err)
+		if h.lg != nil {
+			h.lg.Warn("failed to encode membership members", zap.Error(err))
+		} else {
+			plog.Warningf("failed to encode members response (%v)", err)
+		}
 	}
 }

etcdserver/api/etcdhttp/peer_test.go

@@ -23,6 +23,8 @@ import (
 	"sort"
 	"testing"
 
+	"go.uber.org/zap"
+
 	"github.com/coreos/etcd/etcdserver/membership"
 	"github.com/coreos/etcd/pkg/testutil"
 	"github.com/coreos/etcd/pkg/types"
@@ -55,7 +57,7 @@ func TestNewPeerHandlerOnRaftPrefix(t *testing.T) {
 	h := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("test data"))
 	})
-	ph := newPeerHandler(&fakeCluster{}, h, nil)
+	ph := newPeerHandler(zap.NewExample(), &fakeCluster{}, h, nil)
 	srv := httptest.NewServer(ph)
 	defer srv.Close()