open-consul/agent/retry_join.go

115 lines
2.7 KiB
Go

package agent
import (
"fmt"
"log"
"strings"
"time"
discover "github.com/hashicorp/go-discover"
)
func (a *Agent) retryJoinLAN() {
r := &retryJoiner{
cluster: "LAN",
addrs: a.config.RetryJoin,
maxAttempts: a.config.RetryMaxAttempts,
interval: a.config.RetryInterval,
join: a.JoinLAN,
logger: a.logger,
}
if err := r.retryJoin(); err != nil {
a.retryJoinCh <- err
}
}
func (a *Agent) retryJoinWAN() {
r := &retryJoiner{
cluster: "WAN",
addrs: a.config.RetryJoinWan,
maxAttempts: a.config.RetryMaxAttemptsWan,
interval: a.config.RetryIntervalWan,
join: a.JoinWAN,
logger: a.logger,
}
if err := r.retryJoin(); err != nil {
a.retryJoinCh <- err
}
}
// retryJoiner is used to handle retrying a join until it succeeds or all
// retries are exhausted.
type retryJoiner struct {
// cluster is the name of the serf cluster, e.g. "LAN" or "WAN".
cluster string
// addrs is the list of servers or go-discover configurations
// to join with.
addrs []string
// maxAttempts is the number of join attempts before giving up.
maxAttempts int
// interval is the time between two join attempts.
interval time.Duration
// join adds the discovered or configured servers to the given
// serf cluster.
join func([]string) (int, error)
// logger is the agent logger. Log messages should contain the
// "agent: " prefix.
logger *log.Logger
}
func (r *retryJoiner) retryJoin() error {
if len(r.addrs) == 0 {
return nil
}
disco := discover.Discover{}
r.logger.Printf("[INFO] agent: Retry join %s is supported for: %s", r.cluster, strings.Join(disco.Names(), " "))
r.logger.Printf("[INFO] agent: Joining %s cluster...", r.cluster)
attempt := 0
for {
var addrs []string
var err error
for _, addr := range r.addrs {
switch {
case strings.Contains(addr, "provider="):
servers, err := disco.Addrs(addr, r.logger)
if err != nil {
r.logger.Printf("[ERR] agent: Join %s: %s", r.cluster, err)
} else {
addrs = append(addrs, servers...)
r.logger.Printf("[INFO] agent: Discovered %s servers: %s", r.cluster, strings.Join(servers, " "))
}
default:
addrs = append(addrs, addr)
}
}
if len(addrs) > 0 {
n, err := r.join(addrs)
if err == nil {
r.logger.Printf("[INFO] agent: Join %s completed. Synced with %d initial agents", r.cluster, n)
return nil
}
}
if len(addrs) == 0 {
err = fmt.Errorf("No servers to join")
}
attempt++
if r.maxAttempts > 0 && attempt > r.maxAttempts {
return fmt.Errorf("agent: max join %s retry exhausted, exiting", r.cluster)
}
r.logger.Printf("[WARN] agent: Join %s failed: %v, retrying in %v", r.cluster, err, r.interval)
time.Sleep(r.interval)
}
}