This update provides:
1)  workaround around the build failures. In
summary, it forces the download of some packages during the build
process.
2) update the set of packages that should go inside the vendor
directory
3) Update the dockerfile to use go 1.10

Change-Id: I2bfd090ce0f25b0c10aa214755ae2da7e5384d60
diff --git a/vendor/github.com/coreos/etcd/etcdserver/membership/cluster.go b/vendor/github.com/coreos/etcd/etcdserver/membership/cluster.go
new file mode 100644
index 0000000..4f0b157
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/etcdserver/membership/cluster.go
@@ -0,0 +1,512 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package membership
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha1"
+	"encoding/binary"
+	"encoding/json"
+	"fmt"
+	"path"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/coreos/etcd/mvcc/backend"
+	"github.com/coreos/etcd/pkg/netutil"
+	"github.com/coreos/etcd/pkg/types"
+	"github.com/coreos/etcd/raft"
+	"github.com/coreos/etcd/raft/raftpb"
+	"github.com/coreos/etcd/store"
+	"github.com/coreos/etcd/version"
+
+	"github.com/coreos/go-semver/semver"
+)
+
+// RaftCluster is a list of Members that belong to the same raft cluster
+type RaftCluster struct {
+	id    types.ID
+	token string
+
+	store store.Store
+	be    backend.Backend
+
+	sync.Mutex // guards the fields below
+	version    *semver.Version
+	members    map[types.ID]*Member
+	// removed contains the ids of removed members in the cluster.
+	// removed id cannot be reused.
+	removed map[types.ID]bool
+}
+
+func NewClusterFromURLsMap(token string, urlsmap types.URLsMap) (*RaftCluster, error) {
+	c := NewCluster(token)
+	for name, urls := range urlsmap {
+		m := NewMember(name, urls, token, nil)
+		if _, ok := c.members[m.ID]; ok {
+			return nil, fmt.Errorf("member exists with identical ID %v", m)
+		}
+		if uint64(m.ID) == raft.None {
+			return nil, fmt.Errorf("cannot use %x as member id", raft.None)
+		}
+		c.members[m.ID] = m
+	}
+	c.genID()
+	return c, nil
+}
+
+func NewClusterFromMembers(token string, id types.ID, membs []*Member) *RaftCluster {
+	c := NewCluster(token)
+	c.id = id
+	for _, m := range membs {
+		c.members[m.ID] = m
+	}
+	return c
+}
+
+func NewCluster(token string) *RaftCluster {
+	return &RaftCluster{
+		token:   token,
+		members: make(map[types.ID]*Member),
+		removed: make(map[types.ID]bool),
+	}
+}
+
+func (c *RaftCluster) ID() types.ID { return c.id }
+
+func (c *RaftCluster) Members() []*Member {
+	c.Lock()
+	defer c.Unlock()
+	var ms MembersByID
+	for _, m := range c.members {
+		ms = append(ms, m.Clone())
+	}
+	sort.Sort(ms)
+	return []*Member(ms)
+}
+
+func (c *RaftCluster) Member(id types.ID) *Member {
+	c.Lock()
+	defer c.Unlock()
+	return c.members[id].Clone()
+}
+
+// MemberByName returns a Member with the given name if exists.
+// If more than one member has the given name, it will panic.
+func (c *RaftCluster) MemberByName(name string) *Member {
+	c.Lock()
+	defer c.Unlock()
+	var memb *Member
+	for _, m := range c.members {
+		if m.Name == name {
+			if memb != nil {
+				plog.Panicf("two members with the given name %q exist", name)
+			}
+			memb = m
+		}
+	}
+	return memb.Clone()
+}
+
+func (c *RaftCluster) MemberIDs() []types.ID {
+	c.Lock()
+	defer c.Unlock()
+	var ids []types.ID
+	for _, m := range c.members {
+		ids = append(ids, m.ID)
+	}
+	sort.Sort(types.IDSlice(ids))
+	return ids
+}
+
+func (c *RaftCluster) IsIDRemoved(id types.ID) bool {
+	c.Lock()
+	defer c.Unlock()
+	return c.removed[id]
+}
+
+// PeerURLs returns a list of all peer addresses.
+// The returned list is sorted in ascending lexicographical order.
+func (c *RaftCluster) PeerURLs() []string {
+	c.Lock()
+	defer c.Unlock()
+	urls := make([]string, 0)
+	for _, p := range c.members {
+		urls = append(urls, p.PeerURLs...)
+	}
+	sort.Strings(urls)
+	return urls
+}
+
+// ClientURLs returns a list of all client addresses.
+// The returned list is sorted in ascending lexicographical order.
+func (c *RaftCluster) ClientURLs() []string {
+	c.Lock()
+	defer c.Unlock()
+	urls := make([]string, 0)
+	for _, p := range c.members {
+		urls = append(urls, p.ClientURLs...)
+	}
+	sort.Strings(urls)
+	return urls
+}
+
+func (c *RaftCluster) String() string {
+	c.Lock()
+	defer c.Unlock()
+	b := &bytes.Buffer{}
+	fmt.Fprintf(b, "{ClusterID:%s ", c.id)
+	var ms []string
+	for _, m := range c.members {
+		ms = append(ms, fmt.Sprintf("%+v", m))
+	}
+	fmt.Fprintf(b, "Members:[%s] ", strings.Join(ms, " "))
+	var ids []string
+	for id := range c.removed {
+		ids = append(ids, id.String())
+	}
+	fmt.Fprintf(b, "RemovedMemberIDs:[%s]}", strings.Join(ids, " "))
+	return b.String()
+}
+
+func (c *RaftCluster) genID() {
+	mIDs := c.MemberIDs()
+	b := make([]byte, 8*len(mIDs))
+	for i, id := range mIDs {
+		binary.BigEndian.PutUint64(b[8*i:], uint64(id))
+	}
+	hash := sha1.Sum(b)
+	c.id = types.ID(binary.BigEndian.Uint64(hash[:8]))
+}
+
+func (c *RaftCluster) SetID(id types.ID) { c.id = id }
+
+func (c *RaftCluster) SetStore(st store.Store) { c.store = st }
+
+func (c *RaftCluster) SetBackend(be backend.Backend) {
+	c.be = be
+	mustCreateBackendBuckets(c.be)
+}
+
+func (c *RaftCluster) Recover(onSet func(*semver.Version)) {
+	c.Lock()
+	defer c.Unlock()
+
+	c.members, c.removed = membersFromStore(c.store)
+	c.version = clusterVersionFromStore(c.store)
+	mustDetectDowngrade(c.version)
+	onSet(c.version)
+
+	for _, m := range c.members {
+		plog.Infof("added member %s %v to cluster %s from store", m.ID, m.PeerURLs, c.id)
+	}
+	if c.version != nil {
+		plog.Infof("set the cluster version to %v from store", version.Cluster(c.version.String()))
+	}
+}
+
+// ValidateConfigurationChange takes a proposed ConfChange and
+// ensures that it is still valid.
+func (c *RaftCluster) ValidateConfigurationChange(cc raftpb.ConfChange) error {
+	members, removed := membersFromStore(c.store)
+	id := types.ID(cc.NodeID)
+	if removed[id] {
+		return ErrIDRemoved
+	}
+	switch cc.Type {
+	case raftpb.ConfChangeAddNode:
+		if members[id] != nil {
+			return ErrIDExists
+		}
+		urls := make(map[string]bool)
+		for _, m := range members {
+			for _, u := range m.PeerURLs {
+				urls[u] = true
+			}
+		}
+		m := new(Member)
+		if err := json.Unmarshal(cc.Context, m); err != nil {
+			plog.Panicf("unmarshal member should never fail: %v", err)
+		}
+		for _, u := range m.PeerURLs {
+			if urls[u] {
+				return ErrPeerURLexists
+			}
+		}
+	case raftpb.ConfChangeRemoveNode:
+		if members[id] == nil {
+			return ErrIDNotFound
+		}
+	case raftpb.ConfChangeUpdateNode:
+		if members[id] == nil {
+			return ErrIDNotFound
+		}
+		urls := make(map[string]bool)
+		for _, m := range members {
+			if m.ID == id {
+				continue
+			}
+			for _, u := range m.PeerURLs {
+				urls[u] = true
+			}
+		}
+		m := new(Member)
+		if err := json.Unmarshal(cc.Context, m); err != nil {
+			plog.Panicf("unmarshal member should never fail: %v", err)
+		}
+		for _, u := range m.PeerURLs {
+			if urls[u] {
+				return ErrPeerURLexists
+			}
+		}
+	default:
+		plog.Panicf("ConfChange type should be either AddNode, RemoveNode or UpdateNode")
+	}
+	return nil
+}
+
+// AddMember adds a new Member into the cluster, and saves the given member's
+// raftAttributes into the store. The given member should have empty attributes.
+// A Member with a matching id must not exist.
+func (c *RaftCluster) AddMember(m *Member) {
+	c.Lock()
+	defer c.Unlock()
+	if c.store != nil {
+		mustSaveMemberToStore(c.store, m)
+	}
+	if c.be != nil {
+		mustSaveMemberToBackend(c.be, m)
+	}
+
+	c.members[m.ID] = m
+
+	plog.Infof("added member %s %v to cluster %s", m.ID, m.PeerURLs, c.id)
+}
+
+// RemoveMember removes a member from the store.
+// The given id MUST exist, or the function panics.
+func (c *RaftCluster) RemoveMember(id types.ID) {
+	c.Lock()
+	defer c.Unlock()
+	if c.store != nil {
+		mustDeleteMemberFromStore(c.store, id)
+	}
+	if c.be != nil {
+		mustDeleteMemberFromBackend(c.be, id)
+	}
+
+	delete(c.members, id)
+	c.removed[id] = true
+
+	plog.Infof("removed member %s from cluster %s", id, c.id)
+}
+
+func (c *RaftCluster) UpdateAttributes(id types.ID, attr Attributes) {
+	c.Lock()
+	defer c.Unlock()
+	if m, ok := c.members[id]; ok {
+		m.Attributes = attr
+		if c.store != nil {
+			mustUpdateMemberAttrInStore(c.store, m)
+		}
+		if c.be != nil {
+			mustSaveMemberToBackend(c.be, m)
+		}
+		return
+	}
+	_, ok := c.removed[id]
+	if !ok {
+		plog.Panicf("error updating attributes of unknown member %s", id)
+	}
+	plog.Warningf("skipped updating attributes of removed member %s", id)
+}
+
+func (c *RaftCluster) UpdateRaftAttributes(id types.ID, raftAttr RaftAttributes) {
+	c.Lock()
+	defer c.Unlock()
+
+	c.members[id].RaftAttributes = raftAttr
+	if c.store != nil {
+		mustUpdateMemberInStore(c.store, c.members[id])
+	}
+	if c.be != nil {
+		mustSaveMemberToBackend(c.be, c.members[id])
+	}
+
+	plog.Noticef("updated member %s %v in cluster %s", id, raftAttr.PeerURLs, c.id)
+}
+
+func (c *RaftCluster) Version() *semver.Version {
+	c.Lock()
+	defer c.Unlock()
+	if c.version == nil {
+		return nil
+	}
+	return semver.Must(semver.NewVersion(c.version.String()))
+}
+
+func (c *RaftCluster) SetVersion(ver *semver.Version, onSet func(*semver.Version)) {
+	c.Lock()
+	defer c.Unlock()
+	if c.version != nil {
+		plog.Noticef("updated the cluster version from %v to %v", version.Cluster(c.version.String()), version.Cluster(ver.String()))
+	} else {
+		plog.Noticef("set the initial cluster version to %v", version.Cluster(ver.String()))
+	}
+	c.version = ver
+	mustDetectDowngrade(c.version)
+	if c.store != nil {
+		mustSaveClusterVersionToStore(c.store, ver)
+	}
+	if c.be != nil {
+		mustSaveClusterVersionToBackend(c.be, ver)
+	}
+	onSet(ver)
+}
+
+func (c *RaftCluster) IsReadyToAddNewMember() bool {
+	nmembers := 1
+	nstarted := 0
+
+	for _, member := range c.members {
+		if member.IsStarted() {
+			nstarted++
+		}
+		nmembers++
+	}
+
+	if nstarted == 1 && nmembers == 2 {
+		// a case of adding a new node to 1-member cluster for restoring cluster data
+		// https://github.com/coreos/etcd/blob/master/Documentation/v2/admin_guide.md#restoring-the-cluster
+
+		plog.Debugf("The number of started member is 1. This cluster can accept add member request.")
+		return true
+	}
+
+	nquorum := nmembers/2 + 1
+	if nstarted < nquorum {
+		plog.Warningf("Reject add member request: the number of started member (%d) will be less than the quorum number of the cluster (%d)", nstarted, nquorum)
+		return false
+	}
+
+	return true
+}
+
+func (c *RaftCluster) IsReadyToRemoveMember(id uint64) bool {
+	nmembers := 0
+	nstarted := 0
+
+	for _, member := range c.members {
+		if uint64(member.ID) == id {
+			continue
+		}
+
+		if member.IsStarted() {
+			nstarted++
+		}
+		nmembers++
+	}
+
+	nquorum := nmembers/2 + 1
+	if nstarted < nquorum {
+		plog.Warningf("Reject remove member request: the number of started member (%d) will be less than the quorum number of the cluster (%d)", nstarted, nquorum)
+		return false
+	}
+
+	return true
+}
+
+func membersFromStore(st store.Store) (map[types.ID]*Member, map[types.ID]bool) {
+	members := make(map[types.ID]*Member)
+	removed := make(map[types.ID]bool)
+	e, err := st.Get(StoreMembersPrefix, true, true)
+	if err != nil {
+		if isKeyNotFound(err) {
+			return members, removed
+		}
+		plog.Panicf("get storeMembers should never fail: %v", err)
+	}
+	for _, n := range e.Node.Nodes {
+		var m *Member
+		m, err = nodeToMember(n)
+		if err != nil {
+			plog.Panicf("nodeToMember should never fail: %v", err)
+		}
+		members[m.ID] = m
+	}
+
+	e, err = st.Get(storeRemovedMembersPrefix, true, true)
+	if err != nil {
+		if isKeyNotFound(err) {
+			return members, removed
+		}
+		plog.Panicf("get storeRemovedMembers should never fail: %v", err)
+	}
+	for _, n := range e.Node.Nodes {
+		removed[MustParseMemberIDFromKey(n.Key)] = true
+	}
+	return members, removed
+}
+
+func clusterVersionFromStore(st store.Store) *semver.Version {
+	e, err := st.Get(path.Join(storePrefix, "version"), false, false)
+	if err != nil {
+		if isKeyNotFound(err) {
+			return nil
+		}
+		plog.Panicf("unexpected error (%v) when getting cluster version from store", err)
+	}
+	return semver.Must(semver.NewVersion(*e.Node.Value))
+}
+
+// ValidateClusterAndAssignIDs validates the local cluster by matching the PeerURLs
+// with the existing cluster. If the validation succeeds, it assigns the IDs
+// from the existing cluster to the local cluster.
+// If the validation fails, an error will be returned.
+func ValidateClusterAndAssignIDs(local *RaftCluster, existing *RaftCluster) error {
+	ems := existing.Members()
+	lms := local.Members()
+	if len(ems) != len(lms) {
+		return fmt.Errorf("member count is unequal")
+	}
+	sort.Sort(MembersByPeerURLs(ems))
+	sort.Sort(MembersByPeerURLs(lms))
+
+	ctx, cancel := context.WithTimeout(context.TODO(), 30*time.Second)
+	defer cancel()
+	for i := range ems {
+		if ok, err := netutil.URLStringsEqual(ctx, ems[i].PeerURLs, lms[i].PeerURLs); !ok {
+			return fmt.Errorf("unmatched member while checking PeerURLs (%v)", err)
+		}
+		lms[i].ID = ems[i].ID
+	}
+	local.members = make(map[types.ID]*Member)
+	for _, m := range lms {
+		local.members[m.ID] = m
+	}
+	return nil
+}
+
+func mustDetectDowngrade(cv *semver.Version) {
+	lv := semver.Must(semver.NewVersion(version.Version))
+	// only keep major.minor version for comparison against cluster version
+	lv = &semver.Version{Major: lv.Major, Minor: lv.Minor}
+	if cv != nil && lv.LessThan(*cv) {
+		plog.Fatalf("cluster cannot be downgraded (current version: %s is lower than determined cluster version: %s).", version.Version, version.Cluster(cv.String()))
+	}
+}