// reaper closes idle connections to the cluster.
func (c *ClusterClient) reaper(frequency time.Duration) {
ticker := time.NewTicker(frequency)
defer ticker.Stop()
for _ = range ticker.C {
if c.closed() {
break
}
var n int
for _, client := range c.getClients() {
nn, err := client.connPool.(*pool.ConnPool).ReapStaleConns()
if err != nil {
internal.Logf("ReapStaleConns failed: %s", err)
} else {
n += nn
}
}
s := c.PoolStats()
internal.Logf(
"reaper: removed %d stale conns (TotalConns=%d FreeConns=%d Requests=%d Hits=%d Timeouts=%d)",
n, s.TotalConns, s.FreeConns, s.Requests, s.Hits, s.Timeouts,
)
}
}
// closeOldConns closes connections to the old master after failover switch.
func (d *sentinelFailover) closeOldConns(newMaster string) {
// Good connections that should be put back to the pool. They
// can't be put immediately, because pool.First will return them
// again on next iteration.
cnsToPut := make([]*pool.Conn, 0)
for {
cn := d.pool.PopFree()
if cn == nil {
break
}
if cn.RemoteAddr().String() != newMaster {
err := fmt.Errorf(
"sentinel: closing connection to the old master %s",
cn.RemoteAddr(),
)
internal.Logf(err.Error())
d.pool.Remove(cn, err)
} else {
cnsToPut = append(cnsToPut, cn)
}
}
for _, cn := range cnsToPut {
d.pool.Put(cn)
}
}
func (c *ClusterClient) reloadSlots() {
defer atomic.StoreUint32(&c.reloading, 0)
client, err := c.randomClient()
if err != nil {
internal.Logf("randomClient failed: %s", err)
return
}
slots, err := client.ClusterSlots().Result()
if err != nil {
internal.Logf("ClusterSlots failed: %s", err)
return
}
c.setSlots(slots)
}
func (d *sentinelFailover) MasterAddr() (string, error) {
defer d.mu.Unlock()
d.mu.Lock()
// Try last working sentinel.
if d.sentinel != nil {
addr, err := d.sentinel.GetMasterAddrByName(d.masterName).Result()
if err != nil {
internal.Logf("sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
d._resetSentinel()
} else {
addr := net.JoinHostPort(addr[0], addr[1])
internal.Logf("sentinel: %q addr is %s", d.masterName, addr)
return addr, nil
}
}
for i, sentinelAddr := range d.sentinelAddrs {
sentinel := newSentinel(&Options{
Addr: sentinelAddr,
DialTimeout: d.opt.DialTimeout,
ReadTimeout: d.opt.ReadTimeout,
WriteTimeout: d.opt.WriteTimeout,
PoolSize: d.opt.PoolSize,
PoolTimeout: d.opt.PoolTimeout,
IdleTimeout: d.opt.IdleTimeout,
})
masterAddr, err := sentinel.GetMasterAddrByName(d.masterName).Result()
if err != nil {
internal.Logf("sentinel: GetMasterAddrByName %q failed: %s", d.masterName, err)
sentinel.Close()
continue
}
// Push working sentinel to the top.
d.sentinelAddrs[0], d.sentinelAddrs[i] = d.sentinelAddrs[i], d.sentinelAddrs[0]
d.setSentinel(sentinel)
addr := net.JoinHostPort(masterAddr[0], masterAddr[1])
internal.Logf("sentinel: %q addr is %s", d.masterName, addr)
return addr, nil
}
return "", errors.New("redis: all sentinels are unreachable")
}
func (d *sentinelFailover) listen(sentinel *sentinelClient) {
var pubsub *PubSub
for {
if pubsub == nil {
pubsub = sentinel.PubSub()
if err := pubsub.Subscribe("+switch-master"); err != nil {
internal.Logf("sentinel: Subscribe failed: %s", err)
d.resetSentinel()
return
}
}
msg, err := pubsub.ReceiveMessage()
if err != nil {
internal.Logf("sentinel: ReceiveMessage failed: %s", err)
pubsub.Close()
d.resetSentinel()
return
}
switch msg.Channel {
case "+switch-master":
parts := strings.Split(msg.Payload, " ")
if parts[0] != d.masterName {
internal.Logf("sentinel: ignore new %s addr", parts[0])
continue
}
addr := net.JoinHostPort(parts[3], parts[4])
internal.Logf(
"sentinel: new %q addr is %s",
d.masterName, addr,
)
d.closeOldConns(addr)
}
}
}
func (d *sentinelFailover) discoverSentinels(sentinel *sentinelClient) {
sentinels, err := sentinel.Sentinels(d.masterName).Result()
if err != nil {
internal.Logf("sentinel: Sentinels %q failed: %s", d.masterName, err)
return
}
for _, sentinel := range sentinels {
vals := sentinel.([]interface{})
for i := 0; i < len(vals); i += 2 {
key := vals[i].(string)
if key == "name" {
sentinelAddr := vals[i+1].(string)
if !contains(d.sentinelAddrs, sentinelAddr) {
internal.Logf(
"sentinel: discovered new %q sentinel: %s",
d.masterName, sentinelAddr,
)
d.sentinelAddrs = append(d.sentinelAddrs, sentinelAddr)
}
}
}
}
}