| // 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 etcdserver |
| |
| import ( |
| "time" |
| |
| "github.com/coreos/etcd/etcdserver/membership" |
| "github.com/coreos/etcd/pkg/types" |
| "github.com/coreos/etcd/rafthttp" |
| ) |
| |
| // isConnectedToQuorumSince checks whether the local member is connected to the |
| // quorum of the cluster since the given time. |
| func isConnectedToQuorumSince(transport rafthttp.Transporter, since time.Time, self types.ID, members []*membership.Member) bool { |
| return numConnectedSince(transport, since, self, members) >= (len(members)/2)+1 |
| } |
| |
| // isConnectedSince checks whether the local member is connected to the |
| // remote member since the given time. |
| func isConnectedSince(transport rafthttp.Transporter, since time.Time, remote types.ID) bool { |
| t := transport.ActiveSince(remote) |
| return !t.IsZero() && t.Before(since) |
| } |
| |
| // isConnectedFullySince checks whether the local member is connected to all |
| // members in the cluster since the given time. |
| func isConnectedFullySince(transport rafthttp.Transporter, since time.Time, self types.ID, members []*membership.Member) bool { |
| return numConnectedSince(transport, since, self, members) == len(members) |
| } |
| |
| // numConnectedSince counts how many members are connected to the local member |
| // since the given time. |
| func numConnectedSince(transport rafthttp.Transporter, since time.Time, self types.ID, members []*membership.Member) int { |
| connectedNum := 0 |
| for _, m := range members { |
| if m.ID == self || isConnectedSince(transport, since, m.ID) { |
| connectedNum++ |
| } |
| } |
| return connectedNum |
| } |
| |
| // longestConnected chooses the member with longest active-since-time. |
| // It returns false, if nothing is active. |
| func longestConnected(tp rafthttp.Transporter, membs []types.ID) (types.ID, bool) { |
| var longest types.ID |
| var oldest time.Time |
| for _, id := range membs { |
| tm := tp.ActiveSince(id) |
| if tm.IsZero() { // inactive |
| continue |
| } |
| |
| if oldest.IsZero() { // first longest candidate |
| oldest = tm |
| longest = id |
| } |
| |
| if tm.Before(oldest) { |
| oldest = tm |
| longest = id |
| } |
| } |
| if uint64(longest) == 0 { |
| return longest, false |
| } |
| return longest, true |
| } |
| |
| type notifier struct { |
| c chan struct{} |
| err error |
| } |
| |
| func newNotifier() *notifier { |
| return ¬ifier{ |
| c: make(chan struct{}), |
| } |
| } |
| |
| func (nc *notifier) notify(err error) { |
| nc.err = err |
| close(nc.c) |
| } |