Export client expiration metric to prometheus (#1235)

* export client expiration metric

* finalize

* add path name

* snake case

* change label to `chain`

* trusting period as string

Author: boojamya

relayer/processor/message_processor.go

@@ -141,8 +141,14 @@ func (mp *messageProcessor) shouldUpdateClientNow(ctx context.Context, src, dst
 
 	shouldUpdateClientNow := enoughBlocksPassed && (pastTwoThirdsTrustingPeriod || pastConfiguredClientUpdateThreshold)
 
+	if mp.metrics != nil {
+		timeToExpiration := dst.clientState.TrustingPeriod - time.Since(consensusHeightTime)
+		mp.metrics.SetClientExpiration(src.info.PathName, dst.info.ChainID, dst.clientState.ClientID, fmt.Sprint(dst.clientState.TrustingPeriod.String()), timeToExpiration)
+	}
+
 	if shouldUpdateClientNow {
 		mp.log.Info("Client update threshold condition met",
+			zap.String("path_name", src.info.PathName),
 			zap.String("chain_id", dst.info.ChainID),
 			zap.String("client_id", dst.info.ClientID),
 			zap.Int64("trusting_period", dst.clientState.TrustingPeriod.Milliseconds()),
@@ -249,6 +255,7 @@ func (mp *messageProcessor) assembleMsgUpdateClient(ctx context.Context, src, ds
 				clientConsensusHeight.RevisionHeight+1, src.info.ChainID, err)
 		}
 		mp.log.Debug("Had to query for client trusted IBC header",
+			zap.String("path_name", src.info.PathName),
 			zap.String("chain_id", src.info.ChainID),
 			zap.String("counterparty_chain_id", dst.info.ChainID),
 			zap.String("counterparty_client_id", clientID),

relayer/processor/metrics.go

@@ -1,6 +1,8 @@
 package processor
 
 import (
+	"time"
+
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 )
@@ -12,6 +14,7 @@ type PrometheusMetrics struct {
 	LatestHeightGauge     *prometheus.GaugeVec
 	WalletBalance         *prometheus.GaugeVec
 	FeesSpent             *prometheus.GaugeVec
+	ClientExpiration      *prometheus.GaugeVec
 }
 
 func (m *PrometheusMetrics) AddPacketsObserved(path, chain, channel, port, eventType string, count int) {
@@ -34,10 +37,15 @@ func (m *PrometheusMetrics) SetFeesSpent(chain, key, address, denom string, amou
 	m.FeesSpent.WithLabelValues(chain, key, address, denom).Set(amount)
 }
 
+func (m *PrometheusMetrics) SetClientExpiration(pathName, chain, clientID, trustingPeriod string, timeToExpiration time.Duration) {
+	m.ClientExpiration.WithLabelValues(pathName, chain, clientID, trustingPeriod).Set(timeToExpiration.Seconds())
+}
+
 func NewPrometheusMetrics() *PrometheusMetrics {
 	packetLabels := []string{"path", "chain", "channel", "port", "type"}
 	heightLabels := []string{"chain"}
 	walletLabels := []string{"chain", "key", "address", "denom"}
+	clientExpirationLables := []string{"path_name", "chain", "client_id", "trusting_period"}
 	registry := prometheus.NewRegistry()
 	registerer := promauto.With(registry)
 	return &PrometheusMetrics{
@@ -62,5 +70,9 @@ func NewPrometheusMetrics() *PrometheusMetrics {
 			Name: "cosmos_relayer_fees_spent",
 			Help: "The amount of fees spent from the relayer's wallet",
 		}, walletLabels),
+		ClientExpiration: registerer.NewGaugeVec(prometheus.GaugeOpts{
+			Name: "cosmos_relayer_client_expiration_seconds",
+			Help: "Seconds until the client expires",
+		}, clientExpirationLables),
 	}
 }