More refactoring to make autopilot consul-agnostic

agent/consul/autopilot.go

@@ -3,7 +3,10 @@ package consul
 import (
 	"context"
 	"fmt"
+	"net"
+	"strconv"
 
+	"github.com/armon/go-metrics"
 	"github.com/hashicorp/consul/agent/consul/autopilot"
 	"github.com/hashicorp/consul/agent/metadata"
 	"github.com/hashicorp/raft"
@@ -15,24 +18,52 @@ type AutopilotDelegate struct {
 	server *Server
 }
 
-func (d *AutopilotDelegate) FetchStats(ctx context.Context, servers []*metadata.Server) map[string]*autopilot.ServerStats {
+func (d *AutopilotDelegate) AutopilotConfig() *autopilot.Config {
-	return d.server.statsFetcher.Fetch(ctx, servers)
-}
-
-func (d *AutopilotDelegate) GetOrCreateAutopilotConfig() (*autopilot.Config, bool) {
 	return d.server.getOrCreateAutopilotConfig()
 }
 
-func (d *AutopilotDelegate) Raft() *raft.Raft {
+func (d *AutopilotDelegate) FetchStats(ctx context.Context, servers []serf.Member) map[string]*autopilot.ServerStats {
-	return d.server.raft
+	return d.server.statsFetcher.Fetch(ctx, servers)
 }
 
-func (d *AutopilotDelegate) Serf() *serf.Serf {
+func (d *AutopilotDelegate) IsServer(m serf.Member) (bool, *autopilot.ServerInfo) {
-	return d.server.serfLAN
+	if m.Tags["role"] != "consul" {
+		return false, nil
+	}
+
+	port_str := m.Tags["port"]
+	port, err := strconv.Atoi(port_str)
+	if err != nil {
+		return false, nil
+	}
+
+	build_version, err := metadata.Build(&m)
+	if err != nil {
+		return false, nil
+	}
+
+	return true, &autopilot.ServerInfo{
+		Name:   m.Name,
+		ID:     m.Tags["id"],
+		Addr:   &net.TCPAddr{IP: m.Addr, Port: port},
+		Build:  *build_version,
+		Status: m.Status,
+	}
 }
 
-func (d *AutopilotDelegate) NumPeers() (int, error) {
+// Heartbeat a metric for monitoring if we're the leader
-	return d.server.numPeers()
+func (d *AutopilotDelegate) NotifyHealth(health autopilot.OperatorHealthReply) {
+	if d.server.raft.State() == raft.Leader {
+		metrics.SetGauge([]string{"consul", "autopilot", "failure_tolerance"}, float32(health.FailureTolerance))
+		metrics.SetGauge([]string{"autopilot", "failure_tolerance"}, float32(health.FailureTolerance))
+		if health.Healthy {
+			metrics.SetGauge([]string{"consul", "autopilot", "healthy"}, 1)
+			metrics.SetGauge([]string{"autopilot", "healthy"}, 1)
+		} else {
+			metrics.SetGauge([]string{"consul", "autopilot", "healthy"}, 0)
+			metrics.SetGauge([]string{"autopilot", "healthy"}, 0)
+		}
+	}
 }
 
 func (d *AutopilotDelegate) PromoteNonVoters(conf *autopilot.Config, health autopilot.OperatorHealthReply) ([]raft.Server, error) {
@@ -43,3 +74,11 @@ func (d *AutopilotDelegate) PromoteNonVoters(conf *autopilot.Config, health auto
 
 	return autopilot.PromoteStableServers(conf, health, future.Configuration().Servers), nil
 }
+
+func (d *AutopilotDelegate) Raft() *raft.Raft {
+	return d.server.raft
+}
+
+func (d *AutopilotDelegate) Serf() *serf.Serf {
+	return d.server.serfLAN
+}

agent/consul/autopilot/autopilot.go

@@ -4,21 +4,22 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"net"
 	"strconv"
 	"sync"
 	"time"
 
-	"github.com/armon/go-metrics"
+	"github.com/hashicorp/go-version"
-	"github.com/hashicorp/consul/agent/metadata"
 	"github.com/hashicorp/raft"
 	"github.com/hashicorp/serf/serf"
 )
 
 // Delegate is the interface for the Autopilot mechanism
 type Delegate interface {
-	FetchStats(ctx context.Context, servers []*metadata.Server) map[string]*ServerStats
+	AutopilotConfig() *Config
-	GetOrCreateAutopilotConfig() (*Config, bool)
+	FetchStats(context.Context, []serf.Member) map[string]*ServerStats
-	NumPeers() (int, error)
+	IsServer(serf.Member) (bool, *ServerInfo)
+	NotifyHealth(OperatorHealthReply)
 	PromoteNonVoters(*Config, OperatorHealthReply) ([]raft.Server, error)
 	Raft() *raft.Raft
 	Serf() *serf.Serf
@@ -28,9 +29,8 @@ type Delegate interface {
 // quorum using server health information along with updates from Serf gossip.
 // For more information, see https://www.consul.io/docs/guides/autopilot.html
 type Autopilot struct {
-	logger          *log.Logger
+	logger   *log.Logger
-	delegate        Delegate
+	delegate Delegate
-	validServerFunc func(serf.Member) bool
 
 	interval       time.Duration
 	healthInterval time.Duration
@@ -43,18 +43,25 @@ type Autopilot struct {
 	waitGroup    sync.WaitGroup
 }
 
-func NewAutopilot(logger *log.Logger, delegate Delegate, serverFunc func(serf.Member) bool, interval, healthInterval time.Duration) *Autopilot {
+type ServerInfo struct {
+	Name   string
+	ID     string
+	Addr   net.Addr
+	Build  version.Version
+	Status serf.MemberStatus
+}
+
+func NewAutopilot(logger *log.Logger, delegate Delegate, interval, healthInterval time.Duration) *Autopilot {
 	return &Autopilot{
-		logger:          logger,
+		logger:         logger,
-		delegate:        delegate,
+		delegate:       delegate,
-		validServerFunc: serverFunc,
+		interval:       interval,
-		interval:        interval,
+		healthInterval: healthInterval,
-		healthInterval:  healthInterval,
+		removeDeadCh:   make(chan struct{}),
 	}
 }
 
 func (a *Autopilot) Start() {
-	a.removeDeadCh = make(chan struct{})
 	a.shutdownCh = make(chan struct{})
 	a.waitGroup = sync.WaitGroup{}
 	a.waitGroup.Add(1)
@@ -67,7 +74,7 @@ func (a *Autopilot) Stop() {
 	a.waitGroup.Wait()
 }
 
-// autopilotLoop periodically looks for nonvoting servers to promote and dead servers to remove.
+// run periodically looks for nonvoting servers to promote and dead servers to remove.
 func (a *Autopilot) run() {
 	defer a.waitGroup.Done()
 
@@ -80,8 +87,8 @@ func (a *Autopilot) run() {
 		case <-a.shutdownCh:
 			return
 		case <-ticker.C:
-			autopilotConfig, ok := a.delegate.GetOrCreateAutopilotConfig()
+			autopilotConfig := a.delegate.AutopilotConfig()
-			if !ok {
+			if autopilotConfig == nil {
 				continue
 			}
 
@@ -101,16 +108,16 @@ func (a *Autopilot) run() {
 				}
 			}
 
-			if err := a.pruneDeadServers(autopilotConfig); err != nil {
+			if err := a.pruneDeadServers(); err != nil {
 				a.logger.Printf("[ERR] autopilot: Error checking for dead servers to remove: %s", err)
 			}
 		case <-a.removeDeadCh:
-			autopilotConfig, ok := a.delegate.GetOrCreateAutopilotConfig()
+			autopilotConfig := a.delegate.AutopilotConfig()
-			if !ok {
+			if autopilotConfig == nil {
 				continue
 			}
 
-			if err := a.pruneDeadServers(autopilotConfig); err != nil {
+			if err := a.pruneDeadServers(); err != nil {
 				a.logger.Printf("[ERR] autopilot: Error checking for dead servers to remove: %s", err)
 			}
 		}
@@ -122,12 +129,19 @@ func fmtServer(server raft.Server) string {
 	return fmt.Sprintf("Server (ID: %q Address: %q)", server.ID, server.Address)
 }
 
-// pruneDeadServers removes up to numPeers/2 failed servers
+// NumPeers counts the number of voting peers in the given raft config.
-func (a *Autopilot) pruneDeadServers(conf *Config) error {
+func NumPeers(raftConfig raft.Configuration) int {
-	if !conf.CleanupDeadServers {
+	var numPeers int
-		return nil
+	for _, server := range raftConfig.Servers {
+		if isVoter(server.Suffrage) {
+			numPeers++
+		}
 	}
+	return numPeers
+}
 
+// pruneDeadServers removes up to numPeers/2 failed servers
+func (a *Autopilot) pruneDeadServers() error {
 	// Failed servers are known to Serf and marked failed, and stale servers
 	// are known to Raft but not Serf.
 	var failed []string
@@ -137,13 +151,17 @@ func (a *Autopilot) pruneDeadServers(conf *Config) error {
 	if err := future.Error(); err != nil {
 		return err
 	}
-	for _, server := range future.Configuration().Servers {
+
+	raftConfig := future.Configuration()
+	for _, server := range raftConfig.Servers {
 		staleRaftServers[string(server.Address)] = server
 	}
+
 	serfLAN := a.delegate.Serf()
 	for _, member := range serfLAN.Members() {
-		valid, parts := metadata.IsConsulServer(member)
+		valid, parts := a.delegate.IsServer(member)
 		if valid {
+			// todo(kyhavlov): change this to index by UUID
 			if _, ok := staleRaftServers[parts.Addr.String()]; ok {
 				delete(staleRaftServers, parts.Addr.String())
 			}
@@ -161,10 +179,7 @@ func (a *Autopilot) pruneDeadServers(conf *Config) error {
 	}
 
 	// Only do removals if a minority of servers will be affected.
-	peers, err := a.delegate.NumPeers()
+	peers := NumPeers(raftConfig)
-	if err != nil {
-		return err
-	}
 	if removalCount < peers/2 {
 		for _, node := range failed {
 			a.logger.Printf("[INFO] autopilot: Attempting removal of failed server node %q", node)
@@ -203,7 +218,7 @@ func (a *Autopilot) MinRaftProtocol() (int, error) {
 			continue
 		}
 
-		if !a.validServerFunc(m) {
+		if ok, _ := a.delegate.IsServer(m); !ok {
 			continue
 		}
 
@@ -287,25 +302,24 @@ func (a *Autopilot) updateClusterHealth() error {
 		return nil
 	}
 
-	autopilotConf, ok := a.delegate.GetOrCreateAutopilotConfig()
+	autopilotConf := a.delegate.AutopilotConfig()
-	if !ok {
-		return nil
-	}
 	// Bail early if autopilot config hasn't been initialized yet
 	if autopilotConf == nil {
 		return nil
 	}
 
 	// Get the the serf members which are Consul servers
-	serverMap := make(map[string]*metadata.Server)
+	var serverMembers []serf.Member
+	serverMap := make(map[string]*ServerInfo)
 	for _, member := range a.delegate.Serf().Members() {
 		if member.Status == serf.StatusLeft {
 			continue
 		}
 
-		valid, parts := metadata.IsConsulServer(member)
+		valid, parts := a.delegate.IsServer(member)
 		if valid {
 			serverMap[parts.ID] = parts
+			serverMembers = append(serverMembers, member)
 		}
 	}
 
@@ -320,7 +334,7 @@ func (a *Autopilot) updateClusterHealth() error {
 	// consistent of a sample as possible. We capture the leader's index
 	// here as well so it roughly lines up with the same point in time.
 	targetLastIndex := raftNode.LastIndex()
-	var fetchList []*metadata.Server
+	var fetchList []*ServerInfo
 	for _, server := range servers {
 		if parts, ok := serverMap[string(server.ID)]; ok {
 			fetchList = append(fetchList, parts)
@@ -329,7 +343,7 @@ func (a *Autopilot) updateClusterHealth() error {
 	d := time.Now().Add(a.healthInterval / 2)
 	ctx, cancel := context.WithDeadline(context.Background(), d)
 	defer cancel()
-	fetchedStats := a.delegate.FetchStats(ctx, fetchList)
+	fetchedStats := a.delegate.FetchStats(ctx, serverMembers)
 
 	// Build a current list of server healths
 	leader := raftNode.Leader()
@@ -380,18 +394,7 @@ func (a *Autopilot) updateClusterHealth() error {
 		clusterHealth.FailureTolerance = healthyVoterCount - requiredQuorum
 	}
 
-	// Heartbeat a metric for monitoring if we're the leader
+	a.delegate.NotifyHealth(clusterHealth)
-	if raftNode.State() == raft.Leader {
-		metrics.SetGauge([]string{"consul", "autopilot", "failure_tolerance"}, float32(clusterHealth.FailureTolerance))
-		metrics.SetGauge([]string{"autopilot", "failure_tolerance"}, float32(clusterHealth.FailureTolerance))
-		if clusterHealth.Healthy {
-			metrics.SetGauge([]string{"consul", "autopilot", "healthy"}, 1)
-			metrics.SetGauge([]string{"autopilot", "healthy"}, 1)
-		} else {
-			metrics.SetGauge([]string{"consul", "autopilot", "healthy"}, 0)
-			metrics.SetGauge([]string{"autopilot", "healthy"}, 0)
-		}
-	}
 
 	a.clusterHealthLock.Lock()
 	a.clusterHealth = clusterHealth
@@ -403,7 +406,7 @@ func (a *Autopilot) updateClusterHealth() error {
 // updateServerHealth computes the resulting health of the server based on its
 // fetched stats and the state of the leader.
 func (a *Autopilot) updateServerHealth(health *ServerHealth,
-	server *metadata.Server, stats *ServerStats,
+	server *ServerInfo, stats *ServerStats,
 	autopilotConf *Config, targetLastIndex uint64) error {
 
 	health.LastTerm = stats.LastTerm

agent/consul/leader.go

@@ -329,30 +329,30 @@ func (s *Server) initializeACL() error {
 }
 
 // getOrCreateAutopilotConfig is used to get the autopilot config, initializing it if necessary
-func (s *Server) getOrCreateAutopilotConfig() (*autopilot.Config, bool) {
+func (s *Server) getOrCreateAutopilotConfig() *autopilot.Config {
 	state := s.fsm.State()
 	_, config, err := state.AutopilotConfig()
 	if err != nil {
 		s.logger.Printf("[ERR] autopilot: failed to get config: %v", err)
-		return nil, false
+		return nil
 	}
 	if config != nil {
-		return config, true
+		return config
 	}
 
 	if !ServersMeetMinimumVersion(s.LANMembers(), minAutopilotVersion) {
 		s.logger.Printf("[WARN] autopilot: can't initialize until all servers are >= %s", minAutopilotVersion.String())
-		return nil, false
+		return nil
 	}
 
 	config = s.config.AutopilotConfig
 	req := structs.AutopilotSetConfigRequest{Config: *config}
 	if _, err = s.raftApply(structs.AutopilotRequestType, req); err != nil {
 		s.logger.Printf("[ERR] autopilot: failed to initialize config: %v", err)
-		return nil, false
+		return nil
 	}
 
-	return config, true
+	return config
 }
 
 // reconcileReaped is used to reconcile nodes that have failed and been reaped

agent/consul/server.go

@@ -304,10 +304,7 @@ func NewServerLogger(config *Config, logger *log.Logger, tokens *token.Store) (*
 
 	// Set up autopilot
 	apDelegate := &AutopilotDelegate{s}
-	serverFunc := func(m serf.Member) bool {
+	s.autopilot = autopilot.NewAutopilot(logger, apDelegate, config.AutopilotInterval, config.ServerHealthInterval)
-		return m.Tags["role"] == "consul"
-	}
-	s.autopilot = autopilot.NewAutopilot(logger, apDelegate, serverFunc, config.AutopilotInterval, config.ServerHealthInterval)
 
 	// Initialize the stats fetcher that autopilot will use.
 	s.statsFetcher = NewStatsFetcher(logger, s.connPool, s.config.Datacenter)
@@ -832,13 +829,7 @@ func (s *Server) numPeers() (int, error) {
 		return 0, err
 	}
 
-	var numPeers int
+	return autopilot.NumPeers(future.Configuration()), nil
-	for _, server := range future.Configuration().Servers {
-		if server.Suffrage == raft.Voter {
-			numPeers++
-		}
-	}
-	return numPeers, nil
 }
 
 // JoinLAN is used to have Consul join the inner-DC pool

agent/consul/stats_fetcher.go

@@ -8,6 +8,7 @@ import (
 	"github.com/hashicorp/consul/agent/consul/autopilot"
 	"github.com/hashicorp/consul/agent/metadata"
 	"github.com/hashicorp/consul/agent/pool"
+	"github.com/hashicorp/serf/serf"
 )
 
 // StatsFetcher has two functions for autopilot. First, lets us fetch all the
@@ -56,14 +57,20 @@ func (f *StatsFetcher) fetch(server *metadata.Server, replyCh chan *autopilot.Se
 }
 
 // Fetch will attempt to query all the servers in parallel.
-func (f *StatsFetcher) Fetch(ctx context.Context, servers []*metadata.Server) map[string]*autopilot.ServerStats {
+func (f *StatsFetcher) Fetch(ctx context.Context, members []serf.Member) map[string]*autopilot.ServerStats {
 	type workItem struct {
 		server  *metadata.Server
 		replyCh chan *autopilot.ServerStats
 	}
-	var work []*workItem
+	var servers []*metadata.Server
+	for _, s := range members {
+		if ok, parts := metadata.IsConsulServer(s); ok {
+			servers = append(servers, parts)
+		}
+	}
 
 	// Skip any servers that have inflight requests.
+	var work []*workItem
 	f.inflightLock.Lock()
 	for _, server := range servers {
 		if _, ok := f.inflight[server.ID]; ok {

agent/consul/stats_fetcher_test.go

@@ -47,7 +47,7 @@ func TestStatsFetcher(t *testing.T) {
 	func() {
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 		defer cancel()
-		stats := s1.statsFetcher.Fetch(ctx, servers)
+		stats := s1.statsFetcher.Fetch(ctx, s1.LANMembers())
 		if len(stats) != 3 {
 			t.Fatalf("bad: %#v", stats)
 		}
@@ -73,7 +73,7 @@ func TestStatsFetcher(t *testing.T) {
 
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 		defer cancel()
-		stats := s1.statsFetcher.Fetch(ctx, servers)
+		stats := s1.statsFetcher.Fetch(ctx, s1.LANMembers())
 		if len(stats) != 2 {
 			t.Fatalf("bad: %#v", stats)
 		}