services/horizon/ingest: added 'horizon_ingest_errors_total' metric key

go.mod

@@ -49,7 +49,7 @@ require (
 	github.com/spf13/viper v1.17.0
 	github.com/stellar/go-xdr v0.0.0-20231122183749-b53fb00bcac2
 	github.com/stellar/throttled v2.2.3-0.20190823235211-89d75816f59d+incompatible
-	github.com/stretchr/testify v1.8.4
+	github.com/stretchr/testify v1.9.0
 	github.com/tyler-smith/go-bip39 v0.0.0-20180618194314-52158e4697b8
 	github.com/xdrpp/goxdr v0.1.1
 	google.golang.org/api v0.170.0
@@ -136,7 +136,7 @@ require (
 	github.com/prometheus/procfs v0.12.0 // indirect
 	github.com/sergi/go-diff v0.0.0-20161205080420-83532ca1c1ca // indirect
 	github.com/spf13/cast v1.5.1 // indirect
-	github.com/stretchr/objx v0.5.1 // indirect
+	github.com/stretchr/objx v0.5.2 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	github.com/valyala/fasthttp v1.34.0 // indirect
 	github.com/xeipuuv/gojsonpointer v0.0.0-20151027082146-e0fe6f683076 // indirect

go.sum

@@ -419,18 +419,18 @@ github.com/stellar/throttled v2.2.3-0.20190823235211-89d75816f59d+incompatible/g
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
-github.com/stretchr/objx v0.5.1 h1:4VhoImhV/Bm0ToFkXFi8hXNXwpDRZ/ynw3amt82mzq0=
-github.com/stretchr/objx v0.5.1/go.mod h1:/iHQpkQwBD6DLUmQ4pE+s1TXdob1mORJ4/UFdrifcy0=
+github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
 github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
 github.com/tyler-smith/go-bip39 v0.0.0-20180618194314-52158e4697b8 h1:g3yQGZK+G6dfF/mw/SOwsTMzUVkpT4hB8pHxpbTXkKw=

services/horizon/internal/ingest/fsm.go

@@ -46,6 +46,32 @@ const (
 	ReingestHistoryRange
 )
 
+// provide a name represention for a state
+func (state State) Name() string {
+	switch state {
+	case Start:
+		return "start"
+	case Stop:
+		return "stop"
+	case Build:
+		return "build"
+	case Resume:
+		return "resume"
+	case WaitForCheckpoint:
+		return "waitforcheckpoint"
+	case StressTest:
+		return "stresstest"
+	case VerifyRange:
+		return "verifyrange"
+	case HistoryRange:
+		return "historyrange"
+	case ReingestHistoryRange:
+		return "reingesthistoryrange"
+	default:
+		return "none"
+	}
+}
+
 type stateMachineNode interface {
 	run(*system) (transition, error)
 	String() string
@@ -405,7 +431,7 @@ func (resumeState) GetState() State {
 	return Resume
 }
 
-func (r resumeState) run(s *system) (transition, error) {
+func (r resumeState) run(s *system) (transitionResult transition, errorResult error) {
 	if r.latestSuccessfullyProcessedLedger == 0 {
 		return start(), errors.New("unexpected latestSuccessfullyProcessedLedger value")
 	}

services/horizon/internal/ingest/ingest_history_range_state_test.go

@@ -291,6 +291,7 @@ func (s *ReingestHistoryRangeStateTestSuite) SetupTest() {
 	}
 	s.historyQ.On("GetTx").Return(nil).Once()
 	s.ledgerBackend.On("PrepareRange", s.ctx, ledgerbackend.BoundedRange(100, 200)).Return(nil).Once()
+	s.system.initMetrics()
 }
 
 func (s *ReingestHistoryRangeStateTestSuite) TearDownTest() {

services/horizon/internal/ingest/main.go

@@ -173,6 +173,10 @@ type Metrics struct {
 
 	// ArchiveRequestCounter counts how many http requests are sent to history server
 	HistoryArchiveStatsCounter *prometheus.CounterVec
+
+	// IngestionErrorCounter counts the number of times the live/forward ingestion state machine
+	// encounters an error condition.
+	IngestionErrorCounter *prometheus.CounterVec
 }
 
 type System interface {
@@ -443,6 +447,16 @@ func (s *system) initMetrics() {
 		},
 		[]string{"source", "type"},
 	)
+
+	s.metrics.IngestionErrorCounter = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "horizon", Subsystem: "ingest", Name: "errors_total",
+			Help: "Counters of the number of times the live/forward ingestion state machine encountered an error. " +
+				"'current_state' label has the name of the state that error occurred. " +
+				"'next_state' label has the name of the next state requested from the current_state.",
+		},
+		[]string{"current_state", "next_state"},
+	)
 }
 
 func (s *system) GetCurrentState() State {
@@ -471,6 +485,7 @@ func (s *system) RegisterMetrics(registry *prometheus.Registry) {
 	registry.MustRegister(s.metrics.LoadersStatsSummary)
 	registry.MustRegister(s.metrics.StateVerifyLedgerEntriesCount)
 	registry.MustRegister(s.metrics.HistoryArchiveStatsCounter)
+	registry.MustRegister(s.metrics.IngestionErrorCounter)
 	s.ledgerBackend = ledgerbackend.WithMetrics(s.ledgerBackend, registry, "horizon")
 }
 
@@ -643,6 +658,11 @@ func (s *system) runStateMachine(cur stateMachineNode) error {
 				// so we log these errors using the info log level
 				logger.Info("Error in ingestion state machine")
 			} else {
+				s.Metrics().IngestionErrorCounter.
+					With(prometheus.Labels{
+						"current_state": cur.GetState().Name(),
+						"next_state":    next.node.GetState().Name(),
+					}).Inc()
 				logger.Error("Error in ingestion state machine")
 			}
 		}

services/horizon/internal/ingest/main_test.go

@@ -4,6 +4,7 @@
 	"bytes"
 	"context"
 	"database/sql"
+	"sync"
 	"testing"
 	"time"
 
@@ -113,10 +114,13 @@
 		historyQ: historyQ,
 		ctx:      context.Background(),
 	}
+	reg := setupMetrics(system)
 
 	historyQ.On("GetTx").Return(&sqlx.Tx{}).Once()
-
 	assert.PanicsWithValue(t, "unexpected transaction", func() {
+		defer func() {
+			assertErrorRestartMetrics(reg, "", "", 0, t)
+		}()
 		system.Run()
 	})
 }
@@ -127,12 +131,17 @@
 		historyQ: historyQ,
 		ctx:      context.Background(),
 	}
+	reg := setupMetrics(system)
 
 	historyQ.On("GetTx").Return(nil).Once()
 	historyQ.On("Begin", mock.Anything).Return(errors.New("my error")).Once()
 	historyQ.On("GetTx").Return(&sqlx.Tx{}).Once()
 
 	assert.PanicsWithValue(t, "unexpected transaction", func() {
+		defer func() {
+			// the test triggers error in the first start state exec, so metric is added
+			assertErrorRestartMetrics(reg, "start", "start", 1, t)
+		}()
 		system.Run()
 	})
 }
@@ -144,12 +153,14 @@
 		historyQ: historyQ,
 		ctx:      ctx,
 	}
+	reg := setupMetrics(system)
 
 	historyQ.On("GetTx").Return(nil).Once()
-	historyQ.On("Begin", mock.AnythingOfType("*context.cancelCtx")).Return(errors.New("my error")).Once()
+	historyQ.On("Begin", mock.AnythingOfType("*context.cancelCtx")).Return(context.Canceled).Once()
 
 	cancel()
 	assert.NoError(t, system.runStateMachine(startState{}))
+	assertErrorRestartMetrics(reg, "", "", 0, t)
 }
 
 // TestStateMachineRunReturnsErrorWhenNextStateIsShutdownWithError checks if the
@@ -162,12 +173,61 @@
 		ctx:      context.Background(),
 		historyQ: historyQ,
 	}
+	reg := setupMetrics(system)
 
 	historyQ.On("GetTx").Return(nil).Once()
 
 	err := system.runStateMachine(verifyRangeState{})
 	assert.Error(t, err)
 	assert.EqualError(t, err, "invalid range: [0, 0]")
+	assertErrorRestartMetrics(reg, "verifyrange", "stop", 1, t)
+}
+
+func TestStateMachineRestartEmitsMetric(t *testing.T) {
+	historyQ := &mockDBQ{}
+	ledgerBackend := &mockLedgerBackend{}
+	ctx, cancel := context.WithCancel(context.Background())
+	var wg sync.WaitGroup
+	defer func() {
+		cancel()
+		wg.Wait()
+	}()
+
+	system := &system{
+		ctx:           ctx,
+		historyQ:      historyQ,
+		ledgerBackend: ledgerBackend,
+	}
+
+	ledgerBackend.On("IsPrepared", system.ctx, ledgerbackend.UnboundedRange(101)).Return(true, nil)
+	ledgerBackend.On("GetLedger", system.ctx, uint32(101)).Return(xdr.LedgerCloseMeta{
+		V0: &xdr.LedgerCloseMetaV0{
+			LedgerHeader: xdr.LedgerHeaderHistoryEntry{
+				Header: xdr.LedgerHeader{
+					LedgerSeq:      101,
+					LedgerVersion:  xdr.Uint32(MaxSupportedProtocolVersion),
+					BucketListHash: xdr.Hash{1, 2, 3},
+				},
+			},
+		},
+	}, nil)
+
+	reg := setupMetrics(system)
+
+	historyQ.On("GetTx").Return(nil)
+	historyQ.On("Begin", system.ctx).Return(errors.New("stop state machine"))
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		system.runStateMachine(resumeState{latestSuccessfullyProcessedLedger: 100})
+	}()
+
+	assert.EventuallyWithT(t, func(c *assert.CollectT) {
+		// this checks every 50ms up to 10s total, for at least 3 fsm retries based on a db Begin error
+		// this condition should be met as the fsm retries every second.
+		assertErrorRestartMetrics(reg, "resume", "resume", 3, c)
+	}, 10*time.Second, 50*time.Millisecond, "horizon_ingest_errors_total metric was not incremented on a fsm error")
 }
 
 func TestMaybeVerifyStateGetExpStateInvalidError(t *testing.T) {
@@ -248,6 +308,7 @@
 		historyQ: historyQ,
 		ctx:      context.Background(),
 	}
+	reg := setupMetrics(s)
 
 	historyQ.On("GetTx").Return(nil)
 	historyQ.On("Begin", s.ctx).Return(nil)
@@ -280,6 +341,45 @@
 	}
 	close(getCh)
 	<-doneCh
+	assertErrorRestartMetrics(reg, "", "", 0, t)
+}
+
+func setupMetrics(system *system) *prometheus.Registry {
+	registry := prometheus.NewRegistry()
+	system.initMetrics()
+	registry.Register(system.Metrics().IngestionErrorCounter)
+	return registry
+}
+
+func assertErrorRestartMetrics(reg *prometheus.Registry, assertCurrentState string, assertNextState string, assertRestartCount float64, t assert.TestingT) {
+	assert := assert.New(t)
+	metrics, err := reg.Gather()
+	assert.NoError(err)
+
+	for _, metricFamily := range metrics {
+		if metricFamily.GetName() == "horizon_ingest_errors_total" {
+			assert.Len(metricFamily.GetMetric(), 1)
+			assert.Equal(metricFamily.GetMetric()[0].GetCounter().GetValue(), assertRestartCount)
+			var metricCurrentState = ""
+			var metricNextState = ""
+			for _, label := range metricFamily.GetMetric()[0].GetLabel() {
+				if label.GetName() == "current_state" {
+					metricCurrentState = label.GetValue()
+				}
+				if label.GetName() == "next_state" {
+					metricNextState = label.GetValue()
+				}
+			}
+
+			assert.Equal(metricCurrentState, assertCurrentState)
+			assert.Equal(metricNextState, assertNextState)
+			return
+		}
+	}
+
+	if assertRestartCount > 0.0 {
+		assert.Fail("horizon_ingest_errors_total metrics were not correct")
+	}
 }
 
 type mockDBQ struct {