func (s *Sentinel) updateClusterView(cv *cluster.ClusterView, keepersState cluster.KeepersState) (*cluster.ClusterView, error) {
var wantedMasterID string
if cv.Master == "" {
log.Debugf("trying to find initial master")
// Check for an initial master
if len(keepersState) < 1 {
return nil, fmt.Errorf("cannot init cluster, no keepers registered")
}
if len(keepersState) > 1 {
return nil, fmt.Errorf("cannot init cluster, more than 1 keeper registered")
}
for id, k := range keepersState {
if k.PGState == nil {
return nil, fmt.Errorf("cannot init cluster using keeper %q since its pg state is unknown", id)
}
if !k.PGState.Initialized {
return nil, fmt.Errorf("cannot init cluster using keeper %q since pg instance is not initializied", id)
}
log.Infof("initializing cluster with master: %q", id)
wantedMasterID = id
break
}
} else {
masterID := cv.Master
wantedMasterID = masterID
masterOK := true
master, ok := keepersState[masterID]
if !ok {
return nil, fmt.Errorf("keeper state for master %q not available. This shouldn't happen!", masterID)
}
log.Debugf(spew.Sprintf("masterState: %#v", master))
if !master.Healthy {
log.Infof("master is failed")
masterOK = false
}
// Check that the wanted master is in master state (i.e. check that promotion from standby to master happened)
if !s.isKeeperConverged(master, cv) {
log.Infof("keeper %s not yet master", masterID)
masterOK = false
}
if !masterOK {
log.Infof("trying to find a standby to replace failed master")
bestStandby, err := s.GetBestStandby(cv, keepersState, masterID)
if err != nil {
log.Errorf("error trying to find the best standby: %v", err)
} else {
if bestStandby != masterID {
log.Infof("electing new master: %q", bestStandby)
wantedMasterID = bestStandby
} else {
log.Infof("cannot find a good standby to replace failed master")
}
}
}
}
newCV := cv.Copy()
newKeepersRole := newCV.KeepersRole
// Add new keepersRole from keepersState
for id, _ := range keepersState {
if _, ok := newKeepersRole[id]; !ok {
if err := newKeepersRole.Add(id, ""); err != nil {
// This shouldn't happen
panic(err)
}
}
}
// Setup master role
if cv.Master != wantedMasterID {
newCV.Master = wantedMasterID
newKeepersRole[wantedMasterID].Follow = ""
}
// Setup standbys
if cv.Master == wantedMasterID {
// wanted master is the previous one
masterState := keepersState[wantedMasterID]
if masterState.Healthy && s.isKeeperConverged(masterState, cv) {
for id, _ := range newKeepersRole {
if id == wantedMasterID {
continue
}
newKeepersRole[id].Follow = wantedMasterID
}
}
}
s.updateProxyConf(cv, newCV, keepersState)
if !newCV.Equals(cv) {
newCV.Version = cv.Version + 1
newCV.ChangeTime = time.Now()
}
return newCV, nil
}
func (s *Sentinel) updateClusterView(cv *cluster.ClusterView, membersState cluster.MembersState) (*cluster.ClusterView, error) {
var wantedMasterID string
// Cluster first initialization
if cv.Version == 0 {
log.Debugf("trying to find initial master")
// Check for an initial master
if len(membersState) < 1 {
return nil, fmt.Errorf("cannot init cluster, no members registered")
}
if len(membersState) > 1 {
return nil, fmt.Errorf("cannot init cluster, more than 1 member registered")
}
for id, m := range membersState {
if m.PGState == nil {
return nil, fmt.Errorf("cannot init cluster using member %q since its pg state is unknown", id)
}
log.Infof("Initializing cluster with master: %q", id)
wantedMasterID = id
break
}
} else {
masterID := cv.Master
masterOK := true
master, ok := membersState[masterID]
if !ok {
return nil, fmt.Errorf("member state for master %q not available. This shouldn't happen!", masterID)
}
log.Debugf(spew.Sprintf("masterState: %#v", master))
if !s.isMemberHealthy(master) {
log.Infof("master is failed")
masterOK = false
}
// Check that the wanted master is in master state (i.e. check that promotion from standby to master happened)
if !s.isMemberConverged(master, cv) {
log.Infof("member %s not yet master", masterID)
masterOK = false
}
wantedMasterID = masterID
if !masterOK {
log.Infof("trying to find a standby to replace failed master")
bestStandby, err := s.GetBestStandby(cv, membersState, masterID)
if err != nil {
log.Errorf("error trying to find the best standby: %v", err)
} else {
if bestStandby != masterID {
log.Infof("electing new master: %q", bestStandby)
wantedMasterID = bestStandby
} else {
log.Infof("cannot find a good standby to replace failed master")
}
}
}
}
newCV := cv.Copy()
newMembersRole := newCV.MembersRole
// Add new members from membersState
for id, _ := range membersState {
if _, ok := newMembersRole[id]; !ok {
newMembersRole[id] = &cluster.MemberRole{}
}
}
// Setup master role
if cv.Master != wantedMasterID {
newCV.Master = wantedMasterID
newMembersRole[wantedMasterID] = &cluster.MemberRole{Follow: ""}
}
// Setup standbys
if cv.Master == wantedMasterID {
// wanted master is the previous one
masterState := membersState[wantedMasterID]
if s.isMemberHealthy(masterState) && s.isMemberConverged(masterState, cv) {
for id, _ := range newMembersRole {
if id == wantedMasterID {
continue
}
newMembersRole[id] = &cluster.MemberRole{Follow: wantedMasterID}
}
}
}
if !newCV.Equals(cv) {
newCV.Version = cv.Version + 1
newCV.ChangeTime = time.Now()
}
return newCV, nil
}