Emit heartbeat and node registration events

command/agent/node_endpoint_test.go

@@ -468,7 +468,7 @@ func TestHTTP_NodeQuery(t *testing.T) {
 		if len(n.Events) < 1 {
 			t.Fatalf("Expected node registration event to be populated: %#v", n)
 		}
-		if n.Events[0].Message != "Node Registered" {
+		if n.Events[0].Message != "Node registered" {
 			t.Fatalf("Expected node registration event to be first node event: %#v", n)
 		}
 	})

nomad/fsm.go

@@ -307,7 +307,7 @@ func (n *nomadFSM) applyStatusUpdate(buf []byte, index uint64) interface{} {
 		panic(fmt.Errorf("failed to decode request: %v", err))
 	}
 
-	if err := n.state.UpdateNodeStatus(index, req.NodeID, req.Status); err != nil {
+	if err := n.state.UpdateNodeStatus(index, req.NodeID, req.Status, req.NodeEvent); err != nil {
 		n.logger.Printf("[ERR] nomad.fsm: UpdateNodeStatus failed: %v", err)
 		return err
 	}

nomad/fsm_test.go

@@ -249,6 +249,7 @@ func TestFSM_DeregisterNode(t *testing.T) {
 
 func TestFSM_UpdateNodeStatus(t *testing.T) {
 	t.Parallel()
+	require := require.New(t)
 	fsm := testFSM(t)
 	fsm.blockedEvals.SetEnabled(true)
 
@@ -257,43 +258,39 @@ func TestFSM_UpdateNodeStatus(t *testing.T) {
 		Node: node,
 	}
 	buf, err := structs.Encode(structs.NodeRegisterRequestType, req)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
+	require.NoError(err)
 
 	resp := fsm.Apply(makeLog(buf))
-	if resp != nil {
-		t.Fatalf("resp: %v", resp)
-	}
+	require.Nil(resp)
 
 	// Mark an eval as blocked.
 	eval := mock.Eval()
 	eval.ClassEligibility = map[string]bool{node.ComputedClass: true}
 	fsm.blockedEvals.Block(eval)
 
+	event := &structs.NodeEvent{
+		Message:   "Node ready foo",
+		Subsystem: structs.NodeEventSubsystemCluster,
+		Timestamp: time.Now(),
+	}
 	req2 := structs.NodeUpdateStatusRequest{
-		NodeID: node.ID,
-		Status: structs.NodeStatusReady,
+		NodeID:    node.ID,
+		Status:    structs.NodeStatusReady,
+		NodeEvent: event,
 	}
 	buf, err = structs.Encode(structs.NodeUpdateStatusRequestType, req2)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
+	require.NoError(err)
 
 	resp = fsm.Apply(makeLog(buf))
-	if resp != nil {
-		t.Fatalf("resp: %v", resp)
-	}
+	require.Nil(resp)
 
 	// Verify the status is ready.
 	ws := memdb.NewWatchSet()
 	node, err = fsm.State().NodeByID(ws, req.Node.ID)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if node.Status != structs.NodeStatusReady {
-		t.Fatalf("bad node: %#v", node)
-	}
+	require.NoError(err)
+	require.Equal(structs.NodeStatusReady, node.Status)
+	require.Len(node.Events, 2)
+	require.Equal(event.Message, node.Events[1].Message)
 
 	// Verify the eval was unblocked.
 	testutil.WaitForResult(func() (bool, error) {

nomad/heartbeat.go

@@ -14,6 +14,10 @@ const (
 	// heartbeatNotLeader is the error string returned when the heartbeat request
 	// couldn't be completed since the server is not the leader.
 	heartbeatNotLeader = "failed to reset heartbeat since server is not leader"
+
+	// NodeHeartbeatEventMissed is the event used when the Nodes heartbeat is
+	// missed.
+	NodeHeartbeatEventMissed = "Node heartbeat missed"
 )
 
 var (
@@ -123,8 +127,9 @@ func (s *Server) invalidateHeartbeat(id string) {
 
 	// Make a request to update the node status
 	req := structs.NodeUpdateStatusRequest{
-		NodeID: id,
-		Status: structs.NodeStatusDown,
+		NodeID:    id,
+		Status:    structs.NodeStatusDown,
+		NodeEvent: structs.NewNodeEvent().SetSubsystem(structs.NodeEventSubsystemCluster).SetMessage(NodeHeartbeatEventMissed),
 		WriteRequest: structs.WriteRequest{
 			Region: s.config.Region,
 		},

nomad/heartbeat_test.go

@@ -140,30 +140,26 @@ func TestHeartbeat_ResetHeartbeatTimerLocked_Renew(t *testing.T) {
 
 func TestHeartbeat_InvalidateHeartbeat(t *testing.T) {
 	t.Parallel()
+	require := require.New(t)
 	s1 := TestServer(t, nil)
 	defer s1.Shutdown()
 	testutil.WaitForLeader(t, s1.RPC)
 
 	// Create a node
 	node := mock.Node()
 	state := s1.fsm.State()
-	err := state.UpsertNode(1, node)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
+	require.NoError(state.UpsertNode(1, node))
 
 	// This should cause a status update
 	s1.invalidateHeartbeat(node.ID)
 
 	// Check it is updated
 	ws := memdb.NewWatchSet()
 	out, err := state.NodeByID(ws, node.ID)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-	if !out.TerminalStatus() {
-		t.Fatalf("should update node: %#v", out)
-	}
+	require.NoError(err)
+	require.True(out.TerminalStatus())
+	require.Len(out.Events, 2)
+	require.Equal(NodeHeartbeatEventMissed, out.Events[1].Message)
 }
 
 func TestHeartbeat_ClearHeartbeatTimer(t *testing.T) {

nomad/node_endpoint.go

@@ -40,6 +40,10 @@ const (
 	// NodeEligibilityEventIneligible is used when the nodes eligiblity is marked
 	// ineligible
 	NodeEligibilityEventIneligible = "Node marked as ineligible for scheduling"
+
+	// NodeHeartbeatEventReregistered is the message used when the node becomes
+	// reregistered by the heartbeat.
+	NodeHeartbeatEventReregistered = "Node reregistered by heartbeat"
 )
 
 // Node endpoint is used for client interactions
@@ -367,6 +371,14 @@ func (n *Node) UpdateStatus(args *structs.NodeUpdateStatusRequest, reply *struct
 	// Commit this update via Raft
 	var index uint64
 	if node.Status != args.Status {
+		// Attach an event if we are updating the node status to ready when it
+		// is down via a heartbeat
+		if node.Status == structs.NodeStatusDown && args.NodeEvent == nil {
+			args.NodeEvent = structs.NewNodeEvent().
+				SetSubsystem(structs.NodeEventSubsystemCluster).
+				SetMessage(NodeHeartbeatEventReregistered)
+		}
+
 		_, index, err = n.srv.raftApply(structs.NodeUpdateStatusRequestType, args)
 		if err != nil {
 			n.srv.logger.Printf("[ERR] nomad.client: status update failed: %v", err)

nomad/node_endpoint_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/hashicorp/nomad/acl"
 	"github.com/hashicorp/nomad/helper/uuid"
 	"github.com/hashicorp/nomad/nomad/mock"
+	"github.com/hashicorp/nomad/nomad/state"
 	"github.com/hashicorp/nomad/nomad/structs"
 	"github.com/hashicorp/nomad/testutil"
 	vapi "github.com/hashicorp/vault/api"
@@ -508,6 +509,56 @@ func TestClientEndpoint_UpdateStatus_Vault(t *testing.T) {
 	}
 }
 
+func TestClientEndpoint_UpdateStatus_HeartbeatRecovery(t *testing.T) {
+	t.Parallel()
+	require := require.New(t)
+	s1 := TestServer(t, nil)
+	defer s1.Shutdown()
+	codec := rpcClient(t, s1)
+	testutil.WaitForLeader(t, s1.RPC)
+
+	// Check that we have no client connections
+	require.Empty(s1.connectedNodes())
+
+	// Create the register request but make the node down
+	node := mock.Node()
+	node.Status = structs.NodeStatusDown
+	reg := &structs.NodeRegisterRequest{
+		Node:         node,
+		WriteRequest: structs.WriteRequest{Region: "global"},
+	}
+
+	// Fetch the response
+	var resp structs.NodeUpdateResponse
+	require.NoError(msgpackrpc.CallWithCodec(codec, "Node.Register", reg, &resp))
+
+	// Update the status
+	dereg := &structs.NodeUpdateStatusRequest{
+		NodeID:       node.ID,
+		Status:       structs.NodeStatusInit,
+		WriteRequest: structs.WriteRequest{Region: "global"},
+	}
+	var resp2 structs.NodeUpdateResponse
+	require.NoError(msgpackrpc.CallWithCodec(codec, "Node.UpdateStatus", dereg, &resp2))
+	require.NotZero(resp2.Index)
+
+	// Check for heartbeat interval
+	ttl := resp2.HeartbeatTTL
+	if ttl < s1.config.MinHeartbeatTTL || ttl > 2*s1.config.MinHeartbeatTTL {
+		t.Fatalf("bad: %#v", ttl)
+	}
+
+	// Check for the node in the FSM
+	state := s1.fsm.State()
+	ws := memdb.NewWatchSet()
+	out, err := state.NodeByID(ws, node.ID)
+	require.NoError(err)
+	require.NotNil(out)
+	require.EqualValues(resp2.Index, out.ModifyIndex)
+	require.Len(out.Events, 2)
+	require.Equal(NodeHeartbeatEventReregistered, out.Events[1].Message)
+}
+
 func TestClientEndpoint_Register_GetEvals(t *testing.T) {
 	t.Parallel()
 	s1 := TestServer(t, nil)
@@ -1222,7 +1273,7 @@ func TestClientEndpoint_GetNode(t *testing.T) {
 	if len(resp2.Node.Events) != 1 {
 		t.Fatalf("Did not set node events: %#v", resp2.Node)
 	}
-	if resp2.Node.Events[0].Message != "Node Registered" {
+	if resp2.Node.Events[0].Message != state.NodeRegisterEventRegistered {
 		t.Fatalf("Did not set node register event correctly: %#v", resp2.Node)
 	}
 
@@ -2622,7 +2673,7 @@ func TestClientEndpoint_ListNodes_Blocking(t *testing.T) {
 
 	// Node status update triggers watches
 	time.AfterFunc(100*time.Millisecond, func() {
-		errCh <- state.UpdateNodeStatus(40, node.ID, structs.NodeStatusDown)
+		errCh <- state.UpdateNodeStatus(40, node.ID, structs.NodeStatusDown, nil)
 	})
 
 	req.MinQueryIndex = 38

nomad/server_test.go

@@ -3,15 +3,13 @@ package nomad
 import (
 	"fmt"
 	"io/ioutil"
-	"log"
 	"os"
 	"path"
 	"strings"
 	"testing"
 	"time"
 
 	msgpackrpc "github.com/hashicorp/net-rpc-msgpackrpc"
-	"github.com/hashicorp/nomad/command/agent/consul"
 	"github.com/hashicorp/nomad/helper/testlog"
 	"github.com/hashicorp/nomad/helper/uuid"
 	"github.com/hashicorp/nomad/nomad/mock"
@@ -531,22 +529,22 @@ func TestServer_InvalidSchedulers(t *testing.T) {
 	t.Parallel()
 	require := require.New(t)
 
+	// Set the config to not have the core scheduler
 	config := DefaultConfig()
-	config.DevMode = true
-	config.LogOutput = testlog.NewWriter(t)
-	config.SerfConfig.MemberlistConfig.BindAddr = "127.0.0.1"
-	logger := log.New(config.LogOutput, "", log.LstdFlags)
-	catalog := consul.NewMockCatalog(logger)
+	logger := testlog.Logger(t)
+	s := &Server{
+		config: config,
+		logger: logger,
+	}
 
-	// Set the config to not have the core scheduler
 	config.EnabledSchedulers = []string{"batch"}
-	_, err := NewServer(config, catalog, logger)
+	err := s.setupWorkers()
 	require.NotNil(err)
 	require.Contains(err.Error(), "scheduler not enabled")
 
 	// Set the config to have an unknown scheduler
 	config.EnabledSchedulers = []string{"batch", structs.JobTypeCore, "foo"}
-	_, err = NewServer(config, catalog, logger)
+	err = s.setupWorkers()
 	require.NotNil(err)
 	require.Contains(err.Error(), "foo")
 }

nomad/state/state_store.go

@@ -14,6 +14,16 @@ import (
 	"github.com/hashicorp/nomad/nomad/structs"
 )
 
+const (
+	// NodeRegisterEventReregistered is the message used when the node becomes
+	// reregistered.
+	NodeRegisterEventRegistered = "Node registered"
+
+	// NodeRegisterEventReregistered is the message used when the node becomes
+	// reregistered.
+	NodeRegisterEventReregistered = "Node re-registered"
+)
+
 // IndexEntry is used with the "index" table
 // for managing the latest Raft index affecting a table.
 type IndexEntry struct {
@@ -530,17 +540,23 @@ func (s *StateStore) UpsertNode(index uint64, node *structs.Node) error {
 		// Retain node events that have already been set on the node
 		node.Events = exist.Events
 
+		// If we are transitioning from down, record the re-registration
+		if exist.Status == structs.NodeStatusDown && node.Status != structs.NodeStatusDown {
+			appendNodeEvents(index, node, []*structs.NodeEvent{
+				structs.NewNodeEvent().SetSubsystem(structs.NodeEventSubsystemCluster).
+					SetMessage(NodeRegisterEventReregistered).
+					SetTimestamp(time.Unix(node.StatusUpdatedAt, 0))})
+		}
+
 		node.Drain = exist.Drain                                 // Retain the drain mode
 		node.SchedulingEligibility = exist.SchedulingEligibility // Retain the eligibility
 		node.DrainStrategy = exist.DrainStrategy                 // Retain the drain strategy
 	} else {
 		// Because this is the first time the node is being registered, we should
 		// also create a node registration event
-		nodeEvent := &structs.NodeEvent{
-			Message:   "Node Registered",
-			Subsystem: "Cluster",
-			Timestamp: time.Unix(node.StatusUpdatedAt, 0),
-		}
+		nodeEvent := structs.NewNodeEvent().SetSubsystem(structs.NodeEventSubsystemCluster).
+			SetMessage(NodeRegisterEventRegistered).
+			SetTimestamp(time.Unix(node.StatusUpdatedAt, 0))
 		node.Events = []*structs.NodeEvent{nodeEvent}
 		node.CreateIndex = index
 		node.ModifyIndex = index
@@ -585,7 +601,7 @@ func (s *StateStore) DeleteNode(index uint64, nodeID string) error {
 }
 
 // UpdateNodeStatus is used to update the status of a node
-func (s *StateStore) UpdateNodeStatus(index uint64, nodeID, status string) error {
+func (s *StateStore) UpdateNodeStatus(index uint64, nodeID, status string, event *structs.NodeEvent) error {
 	txn := s.db.Txn(true)
 	defer txn.Abort()
 
@@ -602,6 +618,11 @@ func (s *StateStore) UpdateNodeStatus(index uint64, nodeID, status string) error
 	existingNode := existing.(*structs.Node)
 	copyNode := existingNode.Copy()
 
+	// Add the event if given
+	if event != nil {
+		appendNodeEvents(index, copyNode, []*structs.NodeEvent{event})
+	}
+
 	// Update the status in the copy
 	copyNode.Status = status
 	copyNode.ModifyIndex = index