SOM: slot height (#663)

* wip: slot height tracking

* add slot height metric + SlotHeight type

* implement exporter

* fix: file naming

* share naming + test cov

cmd/monitoring/main.go

@@ -76,18 +76,27 @@ func main() {
 		chainReader,
 		logger.With(log, "component", "source-node-balances"),
 	)
+	slotHeightSourceFactory := monitoring.NewSlotHeightSourceFactory(
+		chainReader,
+		logger.With(log, "component", "souce-slot-height"),
+	)
 	monitor.NetworkSourceFactories = append(monitor.NetworkSourceFactories,
 		nodeBalancesSourceFactory,
+		slotHeightSourceFactory,
 	)
 
+	// exporter names
+	promExporter := "solana-prom-exporter"
+	promMetrics := "solana-metrics"
+
 	// per-feed exporters
 	feedBalancesExporterFactory := exporter.NewFeedBalancesFactory(
-		logger.With(log, "component", "solana-prom-exporter"),
-		metrics.NewFeedBalances(logger.With(log, "component", "solana-metrics")),
+		logger.With(log, "component", promExporter),
+		metrics.NewFeedBalances(logger.With(log, "component", promMetrics)),
 	)
 	reportObservationsFactory := exporter.NewReportObservationsFactory(
 		logger.With(log, "component", "solana-prome-exporter"),
-		metrics.NewReportObservations(logger.With(log, "component", "solana-metrics")),
+		metrics.NewReportObservations(logger.With(log, "component", promMetrics)),
 	)
 	monitor.ExporterFactories = append(monitor.ExporterFactories,
 		feedBalancesExporterFactory,
@@ -96,11 +105,16 @@ func main() {
 
 	// network exporters
 	nodeBalancesExporterFactory := exporter.NewNodeBalancesFactory(
-		logger.With(log, "component", "solana-prom-exporter"),
+		logger.With(log, "component", promExporter),
 		metrics.NewNodeBalances,
 	)
+	slotHeightExporterFactory := exporter.NewSlotHeightFactory(
+		logger.With(log, "component", promExporter),
+		metrics.NewSlotHeight(logger.With(log, "component", promMetrics)),
+	)
 	monitor.NetworkExporterFactories = append(monitor.NetworkExporterFactories,
 		nodeBalancesExporterFactory,
+		slotHeightExporterFactory,
 	)
 
 	monitor.Run()

pkg/monitoring/chain_reader.go

@@ -17,6 +17,7 @@ type ChainReader interface {
 	GetBalance(ctx context.Context, account solana.PublicKey, commitment rpc.CommitmentType) (out *rpc.GetBalanceResult, err error)
 	GetSignaturesForAddressWithOpts(ctx context.Context, account solana.PublicKey, opts *rpc.GetSignaturesForAddressOpts) (out []*rpc.TransactionSignature, err error)
 	GetTransaction(ctx context.Context, txSig solana.Signature, opts *rpc.GetTransactionOpts) (out *rpc.GetTransactionResult, err error)
+	GetSlot(ctx context.Context) (slot uint64, err error)
 }
 
 func NewChainReader(client *rpc.Client) ChainReader {
@@ -50,3 +51,7 @@ func (c *chainReader) GetSignaturesForAddressWithOpts(ctx context.Context, accou
 func (c *chainReader) GetTransaction(ctx context.Context, txSig solana.Signature, opts *rpc.GetTransactionOpts) (out *rpc.GetTransactionResult, err error) {
 	return c.client.GetTransaction(ctx, txSig, opts)
 }
+
+func (c *chainReader) GetSlot(ctx context.Context) (uint64, error) {
+	return c.client.GetSlot(ctx, rpc.CommitmentProcessed) // get latest height
+}

pkg/monitoring/exporter/slotheight.go

@@ -0,0 +1,50 @@
+package exporter
+
+import (
+	"context"
+
+	commonMonitoring "github.com/smartcontractkit/chainlink-common/pkg/monitoring"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/metrics"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+func NewSlotHeightFactory(
+	_ commonMonitoring.Logger,
+	metrics metrics.SlotHeight,
+) commonMonitoring.ExporterFactory {
+	return &slotHeightFactory{
+		metrics,
+	}
+}
+
+type slotHeightFactory struct {
+	metrics metrics.SlotHeight
+}
+
+func (p *slotHeightFactory) NewExporter(
+	params commonMonitoring.ExporterParams,
+) (commonMonitoring.Exporter, error) {
+	return &slotHeight{
+		params.ChainConfig.GetNetworkName(),
+		params.ChainConfig.GetRPCEndpoint(),
+		p.metrics,
+	}, nil
+}
+
+type slotHeight struct {
+	chain, url string
+	metrics    metrics.SlotHeight
+}
+
+func (p *slotHeight) Export(ctx context.Context, data interface{}) {
+	slot, ok := data.(types.SlotHeight)
+	if !ok {
+		return // skip if input could not be parsed
+	}
+
+	p.metrics.Set(slot, p.chain, p.url)
+}
+
+func (p *slotHeight) Cleanup(_ context.Context) {
+	p.metrics.Cleanup()
+}

pkg/monitoring/exporter/slotheight_test.go

@@ -0,0 +1,36 @@
+package exporter
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/mock"
+	"github.com/stretchr/testify/require"
+
+	"github.com/smartcontractkit/chainlink-common/pkg/logger"
+	commonMonitoring "github.com/smartcontractkit/chainlink-common/pkg/monitoring"
+	"github.com/smartcontractkit/chainlink-common/pkg/utils"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/metrics/mocks"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/testutils"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+func TestSlotHeight(t *testing.T) {
+	ctx := utils.Context(t)
+	m := mocks.NewSlotHeight(t)
+	m.On("Set", mock.Anything, mock.Anything, mock.Anything).Once()
+	m.On("Cleanup").Once()
+
+	factory := NewSlotHeightFactory(logger.Test(t), m)
+
+	chainConfig := testutils.GenerateChainConfig()
+	exporter, err := factory.NewExporter(commonMonitoring.ExporterParams{ChainConfig: chainConfig})
+	require.NoError(t, err)
+
+	// happy path
+	exporter.Export(ctx, types.SlotHeight(10))
+	exporter.Cleanup(ctx)
+
+	// test passing uint64 instead of SlotHeight - should not call mock
+	// SlotHeight alias of uint64
+	exporter.Export(ctx, uint64(10))
+}

pkg/monitoring/metrics/metrics.go

@@ -64,6 +64,14 @@ func init() {
 		},
 		feedLabels,
 	)
+
+	// init gauge for slot height
+	gauges[types.SlotHeightMetric] = promauto.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: types.SlotHeightMetric,
+		},
+		[]string{"chain", "url"},
+	)
 }
 
 type FeedInput struct {

pkg/monitoring/metrics/slotheight.go

@@ -0,0 +1,37 @@
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	commonMonitoring "github.com/smartcontractkit/chainlink-common/pkg/monitoring"
+
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+//go:generate mockery --name SlotHeight --output ./mocks/
+
+type SlotHeight interface {
+	Set(slot types.SlotHeight, chain, url string)
+	Cleanup()
+}
+
+var _ SlotHeight = (*slotHeight)(nil)
+
+type slotHeight struct {
+	simpleGauge
+	labels prometheus.Labels
+}
+
+func NewSlotHeight(log commonMonitoring.Logger) *slotHeight {
+	return &slotHeight{
+		simpleGauge: newSimpleGauge(log, types.SlotHeightMetric),
+	}
+}
+
+func (sh *slotHeight) Set(slot types.SlotHeight, chain, url string) {
+	sh.labels = prometheus.Labels{"chain": chain, "url": url}
+	sh.set(float64(slot), sh.labels)
+}
+
+func (sh *slotHeight) Cleanup() {
+	sh.delete(sh.labels)
+}

pkg/monitoring/metrics/slotheight_test.go

@@ -0,0 +1,38 @@
+package metrics
+
+import (
+	"testing"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/testutil"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/smartcontractkit/chainlink-common/pkg/logger"
+
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+func TestSlotHeight(t *testing.T) {
+	lgr := logger.Test(t)
+	m := NewSlotHeight(lgr)
+
+	// fetching gauges
+	g, ok := gauges[types.SlotHeightMetric]
+	require.True(t, ok)
+
+	v := 100
+
+	// set gauge
+	assert.NotPanics(t, func() { m.Set(types.SlotHeight(v), t.Name(), t.Name()+"_url") })
+	promBal := testutil.ToFloat64(g.With(prometheus.Labels{
+		"chain": t.Name(),
+		"url":   t.Name() + "_url",
+	}))
+	assert.Equal(t, float64(v), promBal)
+
+	// cleanup gauges
+	assert.Equal(t, 1, testutil.CollectAndCount(g))
+	assert.NotPanics(t, func() { m.Cleanup() })
+	assert.Equal(t, 0, testutil.CollectAndCount(g))
+}

pkg/monitoring/source_slotheight.go

@@ -0,0 +1,44 @@
+package monitoring
+
+import (
+	"context"
+
+	commonMonitoring "github.com/smartcontractkit/chainlink-common/pkg/monitoring"
+
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+func NewSlotHeightSourceFactory(
+	client ChainReader,
+	log commonMonitoring.Logger,
+) commonMonitoring.NetworkSourceFactory {
+	return &slotHeightSourceFactory{
+		client,
+		log,
+	}
+}
+
+type slotHeightSourceFactory struct {
+	client ChainReader
+	log    commonMonitoring.Logger
+}
+
+func (s *slotHeightSourceFactory) NewSource(
+	_ commonMonitoring.ChainConfig,
+	_ []commonMonitoring.NodeConfig,
+) (commonMonitoring.Source, error) {
+	return &slotHeightSource{s.client}, nil
+}
+
+func (s *slotHeightSourceFactory) GetType() string {
+	return types.SlotHeightType
+}
+
+type slotHeightSource struct {
+	client ChainReader
+}
+
+func (t *slotHeightSource) Fetch(ctx context.Context) (interface{}, error) {
+	slot, err := t.client.GetSlot(ctx)
+	return types.SlotHeight(slot), err
+}

pkg/monitoring/source_slotheight_test.go

@@ -0,0 +1,34 @@
+package monitoring
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+	"github.com/stretchr/testify/require"
+
+	"github.com/smartcontractkit/chainlink-common/pkg/logger"
+	"github.com/smartcontractkit/chainlink-common/pkg/utils"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/mocks"
+	"github.com/smartcontractkit/chainlink-solana/pkg/monitoring/types"
+)
+
+func TestSlotHeightSource(t *testing.T) {
+	cr := mocks.NewChainReader(t)
+	lgr := logger.Test(t)
+	ctx := utils.Context(t)
+
+	factory := NewSlotHeightSourceFactory(cr, lgr)
+	assert.Equal(t, types.SlotHeightType, factory.GetType())
+
+	// generate source
+	source, err := factory.NewSource(nil, nil)
+	cr.On("GetSlot", mock.Anything, mock.Anything, mock.Anything).Return(uint64(1), nil).Once()
+
+	// happy path
+	out, err := source.Fetch(ctx)
+	require.NoError(t, err)
+	slot, ok := out.(types.SlotHeight)
+	require.True(t, ok)
+	assert.Equal(t, types.SlotHeight(1), slot)
+}