etcdserver: refactor ValidateClusterAndAssignIDs

etcdserver/cluster.go

@@ -226,33 +226,6 @@ func (c *Cluster) String() string {
 	return strings.Join(sl, ",")
 }
 
-// ValidateAndAssignIDs validates the given members by matching their PeerURLs
-// with the existing members in the cluster. If the validation succeeds, it
-// assigns the IDs from the given members to the existing members in the
-// cluster. If the validation fails, an error will be returned.
-func (c *Cluster) ValidateAndAssignIDs(membs []*Member) error {
-	if len(c.members) != len(membs) {
-		return fmt.Errorf("member count is unequal")
-	}
-	omembs := make([]*Member, 0)
-	for _, m := range c.members {
-		omembs = append(omembs, m)
-	}
-	sort.Sort(SortableMemberSliceByPeerURLs(omembs))
-	sort.Sort(SortableMemberSliceByPeerURLs(membs))
-	for i := range omembs {
-		if !reflect.DeepEqual(omembs[i].PeerURLs, membs[i].PeerURLs) {
-			return fmt.Errorf("unmatched member while checking PeerURLs")
-		}
-		omembs[i].ID = membs[i].ID
-	}
-	c.members = make(map[types.ID]*Member)
-	for _, m := range omembs {
-		c.members[m.ID] = m
-	}
-	return nil
-}
-
 func (c *Cluster) genID() {
 	mIDs := c.MemberIDs()
 	b := make([]byte, 8*len(mIDs))
@@ -442,6 +415,32 @@ func membersFromStore(st store.Store) (map[types.ID]*Member, map[types.ID]bool)
 	return members, removed
 }
 
+// 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 *Cluster, existing *Cluster) error {
+	ems := existing.Members()
+	lms := local.Members()
+	if len(ems) != len(lms) {
+		return fmt.Errorf("member count is unequal")
+	}
+	sort.Sort(SortableMemberSliceByPeerURLs(ems))
+	sort.Sort(SortableMemberSliceByPeerURLs(lms))
+
+	for i := range ems {
+		if !reflect.DeepEqual(ems[i].PeerURLs, lms[i].PeerURLs) {
+			return fmt.Errorf("unmatched member while checking PeerURLs")
+		}
+		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 isKeyNotFound(err error) bool {
 	e, ok := err.(*etcdErr.Error)
 	return ok && e.ErrorCode == etcdErr.EcodeKeyNotFound

etcdserver/cluster_test.go

@@ -317,8 +317,9 @@ func TestClusterValidateAndAssignIDsBad(t *testing.T) {
 		},
 	}
 	for i, tt := range tests {
-		cl := newTestCluster(tt.clmembs)
-		if err := cl.ValidateAndAssignIDs(tt.membs); err == nil {
+		ecl := newTestCluster(tt.clmembs)
+		lcl := newTestCluster(tt.membs)
+		if err := ValidateClusterAndAssignIDs(lcl, ecl); err == nil {
 			t.Errorf("#%d: unexpected update success", i)
 		}
 	}
@@ -343,12 +344,13 @@ func TestClusterValidateAndAssignIDs(t *testing.T) {
 		},
 	}
 	for i, tt := range tests {
-		cl := newTestCluster(tt.clmembs)
-		if err := cl.ValidateAndAssignIDs(tt.membs); err != nil {
+		lcl := newTestCluster(tt.clmembs)
+		ecl := newTestCluster(tt.membs)
+		if err := ValidateClusterAndAssignIDs(lcl, ecl); err != nil {
 			t.Errorf("#%d: unexpect update error: %v", i, err)
 		}
-		if !reflect.DeepEqual(cl.MemberIDs(), tt.wids) {
-			t.Errorf("#%d: ids = %v, want %v", i, cl.MemberIDs(), tt.wids)
+		if !reflect.DeepEqual(lcl.MemberIDs(), tt.wids) {
+			t.Errorf("#%d: ids = %v, want %v", i, lcl.MemberIDs(), tt.wids)
 		}
 	}
 }

etcdserver/server.go

@@ -203,14 +203,14 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 	switch {
 	case !haveWAL && !cfg.NewCluster:
 		us := getOtherPeerURLs(cfg.Cluster, cfg.Name)
-		cl, err := GetClusterFromPeers(us)
+		existingCluster, err := GetClusterFromPeers(us)
 		if err != nil {
 			return nil, fmt.Errorf("cannot fetch cluster info from peer urls: %v", err)
 		}
-		if err := cfg.Cluster.ValidateAndAssignIDs(cl.Members()); err != nil {
-			return nil, fmt.Errorf("error validating IDs from cluster %s: %v", cl, err)
+		if err := ValidateClusterAndAssignIDs(cfg.Cluster, existingCluster); err != nil {
+			return nil, fmt.Errorf("error validating peerURLs %s: %v", existingCluster, err)
 		}
-		cfg.Cluster.SetID(cl.id)
+		cfg.Cluster.SetID(existingCluster.id)
 		cfg.Cluster.SetStore(st)
 		cfg.Print()
 		id, n, w = startNode(cfg, nil)