open-consul/agent/consul/client_serf.go

188 lines
5.2 KiB
Go

package consul
import (
"fmt"
"path/filepath"
"strings"
"github.com/hashicorp/consul/agent/metadata"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/lib"
"github.com/hashicorp/consul/logging"
"github.com/hashicorp/consul/types"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/serf/serf"
)
// setupSerf is used to setup and initialize a Serf
func (c *Client) setupSerf(conf *serf.Config, ch chan serf.Event, path string) (*serf.Serf, error) {
conf.Init()
conf.NodeName = c.config.NodeName
conf.Tags["role"] = "node"
conf.Tags["dc"] = c.config.Datacenter
conf.Tags["segment"] = c.config.Segment
conf.Tags["id"] = string(c.config.NodeID)
conf.Tags["vsn"] = fmt.Sprintf("%d", c.config.ProtocolVersion)
conf.Tags["vsn_min"] = fmt.Sprintf("%d", ProtocolVersionMin)
conf.Tags["vsn_max"] = fmt.Sprintf("%d", ProtocolVersionMax)
conf.Tags["build"] = c.config.Build
if c.acls.ACLsEnabled() {
// we start in legacy mode and then transition to normal
// mode once we know the cluster can handle it.
conf.Tags["acls"] = string(structs.ACLModeLegacy)
} else {
conf.Tags["acls"] = string(structs.ACLModeDisabled)
}
// We use the Intercept variant here to ensure that serf and memberlist logs
// can be streamed via the monitor endpoint
serfLogger := c.logger.
NamedIntercept(logging.Serf).
NamedIntercept(logging.LAN).
StandardLoggerIntercept(&hclog.StandardLoggerOptions{InferLevels: true})
memberlistLogger := c.logger.
NamedIntercept(logging.Memberlist).
NamedIntercept(logging.LAN).
StandardLoggerIntercept(&hclog.StandardLoggerOptions{InferLevels: true})
conf.MemberlistConfig.Logger = memberlistLogger
conf.Logger = serfLogger
conf.EventCh = ch
conf.ProtocolVersion = protocolVersionMap[c.config.ProtocolVersion]
conf.RejoinAfterLeave = c.config.RejoinAfterLeave
conf.Merge = &lanMergeDelegate{
dc: c.config.Datacenter,
nodeID: c.config.NodeID,
nodeName: c.config.NodeName,
segment: c.config.Segment,
}
conf.SnapshotPath = filepath.Join(c.config.DataDir, path)
if err := lib.EnsurePath(conf.SnapshotPath, false); err != nil {
return nil, err
}
c.addEnterpriseSerfTags(conf.Tags)
return serf.Create(conf)
}
// lanEventHandler is used to handle events from the lan Serf cluster
func (c *Client) lanEventHandler() {
var numQueuedEvents int
for {
numQueuedEvents = len(c.eventCh)
if numQueuedEvents > serfEventBacklogWarning {
c.logger.Warn("number of queued serf events above warning threshold",
"queued_events", numQueuedEvents,
"warning_threshold", serfEventBacklogWarning,
)
}
select {
case e := <-c.eventCh:
switch e.EventType() {
case serf.EventMemberJoin:
c.nodeJoin(e.(serf.MemberEvent))
case serf.EventMemberLeave, serf.EventMemberFailed, serf.EventMemberReap:
c.nodeFail(e.(serf.MemberEvent))
case serf.EventUser:
c.localEvent(e.(serf.UserEvent))
case serf.EventMemberUpdate: // Ignore
c.nodeUpdate(e.(serf.MemberEvent))
case serf.EventQuery: // Ignore
default:
c.logger.Warn("unhandled LAN Serf Event", "event", e)
}
case <-c.shutdownCh:
return
}
}
}
// nodeJoin is used to handle join events on the serf cluster
func (c *Client) nodeJoin(me serf.MemberEvent) {
for _, m := range me.Members {
ok, parts := metadata.IsConsulServer(m)
if !ok {
continue
}
if parts.Datacenter != c.config.Datacenter {
c.logger.Warn("server has joined the wrong cluster: wrong datacenter",
"server", m.Name,
"datacenter", parts.Datacenter,
)
continue
}
c.logger.Info("adding server", "server", parts)
c.router.AddServer(types.AreaLAN, parts)
// Trigger the callback
if c.config.ServerUp != nil {
c.config.ServerUp()
}
}
}
// nodeUpdate is used to handle update events on the serf cluster
func (c *Client) nodeUpdate(me serf.MemberEvent) {
for _, m := range me.Members {
ok, parts := metadata.IsConsulServer(m)
if !ok {
continue
}
if parts.Datacenter != c.config.Datacenter {
c.logger.Warn("server has joined the wrong cluster: wrong datacenter",
"server", m.Name,
"datacenter", parts.Datacenter,
)
continue
}
c.logger.Info("updating server", "server", parts.String())
c.router.AddServer(types.AreaLAN, parts)
}
}
// nodeFail is used to handle fail events on the serf cluster
func (c *Client) nodeFail(me serf.MemberEvent) {
for _, m := range me.Members {
ok, parts := metadata.IsConsulServer(m)
if !ok {
continue
}
c.logger.Info("removing server", "server", parts.String())
c.router.RemoveServer(types.AreaLAN, parts)
}
}
// localEvent is called when we receive an event on the local Serf
func (c *Client) localEvent(event serf.UserEvent) {
// Handle only consul events
if !strings.HasPrefix(event.Name, "consul:") {
return
}
switch name := event.Name; {
case name == newLeaderEvent:
c.logger.Info("New leader elected", "payload", string(event.Payload))
// Trigger the callback
if c.config.ServerUp != nil {
c.config.ServerUp()
}
case isUserEvent(name):
event.Name = rawUserEventName(name)
c.logger.Debug("user event", "name", event.Name)
// Trigger the callback
if c.config.UserEventHandler != nil {
c.config.UserEventHandler(event)
}
default:
if !c.handleEnterpriseUserEvents(event) {
c.logger.Warn("Unhandled local event", "event", event)
}
}
}