open-consul/consul/servers/serf_flooder.go
2017-03-16 23:38:15 -07:00

85 lines
2.3 KiB
Go

package servers
import (
"fmt"
"log"
"net"
"strings"
"github.com/hashicorp/consul/consul/agent"
"github.com/hashicorp/serf/serf"
)
// FloodPortFn gets the port to use for a given server when flood-joining. This
// will return false if it doesn't have one.
type FloodPortFn func(*agent.Server) (int, bool)
// FloodJoins attempts to make sure all Consul servers in the local Serf
// instance are joined in the global Serf instance. It assumes names in the
// local area are of the form <node> and those in the global area are of the
// form <node>.<dc> as is done for WAN and general network areas in Consul
// Enterprise.
func FloodJoins(logger *log.Logger, portFn FloodPortFn,
localDatacenter string, localSerf *serf.Serf, globalSerf *serf.Serf) {
// Names in the global Serf have the datacenter suffixed.
suffix := fmt.Sprintf(".%s", localDatacenter)
// Index the global side so we can do one pass through the local side
// with cheap lookups.
index := make(map[string]*agent.Server)
for _, m := range globalSerf.Members() {
ok, server := agent.IsConsulServer(m)
if !ok {
continue
}
if server.Datacenter != localDatacenter {
continue
}
localName := strings.TrimSuffix(server.Name, suffix)
index[localName] = server
}
// Now run through the local side and look for joins.
for _, m := range localSerf.Members() {
if m.Status != serf.StatusAlive {
continue
}
ok, server := agent.IsConsulServer(m)
if !ok {
continue
}
if _, ok := index[server.Name]; ok {
continue
}
// We can't use the port number from the local Serf, so we just
// get the host part.
addr, _, err := net.SplitHostPort(server.Addr.String())
if err != nil {
logger.Printf("[DEBUG] consul: Failed to flood-join %q (bad address %q): %v",
server.Name, server.Addr.String(), err)
}
// Let the callback see if it can get the port number, otherwise
// leave it blank to behave as if we just supplied an address.
if port, ok := portFn(server); ok {
addr = net.JoinHostPort(addr, fmt.Sprintf("%d", port))
}
// Do the join!
n, err := globalSerf.Join([]string{addr}, true)
if err != nil {
logger.Printf("[DEBUG] consul: Failed to flood-join %q at %s: %v",
server.Name, addr, err)
} else if n > 0 {
logger.Printf("[DEBUG] consul: Successfully performed flood-join for %q at %s",
server.Name, addr)
}
}
}