metrics, instrumented clients, already known nonce handling and retry

op-ufm/go.mod

@@ -4,31 +4,61 @@ go 1.20
 
 require (
 	github.com/BurntSushi/toml v1.3.2
+	github.com/ethereum-optimism/optimism/op-service v0.10.14-0.20230209153120-0338ea88dff7
 	github.com/ethereum-optimism/optimism/op-signer v0.1.1
 	github.com/ethereum/go-ethereum v1.12.0
 	github.com/gorilla/mux v1.8.0
 	github.com/pkg/errors v0.9.1
+	github.com/prometheus/client_golang v1.14.0
 	github.com/rs/cors v1.8.2
 )
 
 require (
+	github.com/DataDog/zstd v1.5.2 // indirect
+	github.com/VictoriaMetrics/fastcache v1.10.0 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/cockroachdb/errors v1.9.1 // indirect
+	github.com/cockroachdb/logtags v0.0.0-20230118201751-21c54148d20b // indirect
+	github.com/cockroachdb/pebble v0.0.0-20230209160836-829675f94811 // indirect
+	github.com/cockroachdb/redact v1.1.3 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
 	github.com/deckarep/golang-set/v2 v2.1.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0 // indirect
-	github.com/ethereum-optimism/optimism/op-service v0.10.14-0.20230209153120-0338ea88dff7 // indirect
 	github.com/fsnotify/fsnotify v1.6.0 // indirect
+	github.com/getsentry/sentry-go v0.18.0 // indirect
 	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/go-stack/stack v1.8.1 // indirect
+	github.com/gofrs/flock v0.8.1 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/snappy v0.0.5-0.20220116011046-fa5810519dcb // indirect
 	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/holiman/bloomfilter/v2 v2.0.3 // indirect
 	github.com/holiman/uint256 v1.2.2-0.20230321075855-87b91420868c // indirect
+	github.com/klauspost/compress v1.15.15 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/mattn/go-runewidth v0.0.13 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/olekukonko/tablewriter v0.0.5 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.39.0 // indirect
+	github.com/prometheus/procfs v0.9.0 // indirect
+	github.com/rivo/uniseg v0.3.4 // indirect
+	github.com/rogpeppe/go-internal v1.9.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/shirou/gopsutil v3.21.11+incompatible // indirect
+	github.com/syndtr/goleveldb v1.0.1-0.20220614013038-64ee5596c38a // indirect
 	github.com/tklauser/go-sysconf v0.3.10 // indirect
 	github.com/tklauser/numcpus v0.5.0 // indirect
 	github.com/urfave/cli v1.22.9 // indirect
 	github.com/yusufpapurcu/wmi v1.2.2 // indirect
 	golang.org/x/crypto v0.1.0 // indirect
+	golang.org/x/exp v0.0.0-20230206171751-46f607a40771 // indirect
 	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/text v0.8.0 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
 	gopkg.in/natefinch/npipe.v2 v2.0.0-20160621034901-c1b8fa8bdcce // indirect
 )

op-ufm/pkg/config/config.go

@@ -57,12 +57,17 @@ type ProviderConfig struct {
 	Disabled bool   `toml:"disabled"`
 	Network  string `toml:"network"`
 	URL      string `toml:"url"`
+
 	ReadOnly     bool         `toml:"read_only"`
 	ReadInterval TOMLDuration `toml:"read_interval"`
+
 	SendInterval                 TOMLDuration `toml:"send_interval"`
-	Wallet                   string       `toml:"wallet"`
+	SendTransactionRetryInterval TOMLDuration `toml:"send_transaction_retry_interval"`
+	SendTransactionRetryTimeout  TOMLDuration `toml:"send_transaction_retry_timeout"`
 	ReceiptRetrievalInterval     TOMLDuration `toml:"receipt_retrieval_interval"`
 	ReceiptRetrievalTimeout      TOMLDuration `toml:"receipt_retrieval_timeout"`
+
+	Wallet string `toml:"wallet"`
 }
 
 func New(file string) (*Config, error) {
@@ -143,8 +148,11 @@ func (c *Config) Validate() error {
 		if provider.SendInterval == 0 {
 			return errors.Errorf("provider [%s] send_interval is missing", name)
 		}
-		if provider.Wallet == "" {
-			return errors.Errorf("provider [%s] wallet is missing", name)
+		if provider.SendTransactionRetryInterval == 0 {
+			return errors.Errorf("provider [%s] send_transaction_retry_interval is missing", name)
+		}
+		if provider.SendTransactionRetryTimeout == 0 {
+			return errors.Errorf("provider [%s] send_transaction_retry_timeout is missing", name)
 		}
 		if provider.ReceiptRetrievalInterval == 0 {
 			return errors.Errorf("provider [%s] receipt_retrieval_interval is missing", name)
@@ -152,6 +160,9 @@ func (c *Config) Validate() error {
 		if provider.ReceiptRetrievalTimeout == 0 {
 			return errors.Errorf("provider [%s] receipt_retrieval_timeout is missing", name)
 		}
+		if provider.Wallet == "" {
+			return errors.Errorf("provider [%s] wallet is missing", name)
+		}
 		if _, ok := c.Wallets[provider.Wallet]; !ok {
 			return errors.Errorf("provider [%s] has an invalid wallet [%s]", name, provider.Wallet)
 		}

op-ufm/pkg/metrics/clients/eth.go

+package clients
+
+import (
+	"context"
+	"op-ufm/pkg/metrics"
+	"time"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/txpool"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethclient"
+)
+
+type InstrumentedEthClient struct {
+	c            *ethclient.Client
+	providerName string
+}
+
+func Dial(providerName string, url string) (*InstrumentedEthClient, error) {
+	start := time.Now()
+	c, err := ethclient.Dial(url)
+	if err != nil {
+		metrics.RecordError(providerName, "ethclient.Dial")
+		return nil, err
+	}
+	metrics.RecordRPCLatency(providerName, "ethclient", "Dial", time.Since(start))
+	return &InstrumentedEthClient{c: c, providerName: providerName}, nil
+}
+
+func (i *InstrumentedEthClient) TransactionByHash(ctx context.Context, hash common.Hash) (*types.Transaction, bool, error) {
+	start := time.Now()
+	tx, isPending, err := i.c.TransactionByHash(ctx, hash)
+	if err != nil {
+		if !i.IgnorableErrors(err) {
+			metrics.RecordError(i.providerName, "ethclient.TransactionByHash")
+		}
+		return nil, false, err
+	}
+	metrics.RecordRPCLatency(i.providerName, "ethclient", "TransactionByHash", time.Since(start))
+	return tx, isPending, err
+}
+
+func (i *InstrumentedEthClient) PendingNonceAt(ctx context.Context, address string) (uint64, error) {
+	start := time.Now()
+	nonce, err := i.c.PendingNonceAt(ctx, common.HexToAddress(address))
+	if err != nil {
+		metrics.RecordError(i.providerName, "ethclient.PendingNonceAt")
+		return 0, err
+	}
+	metrics.RecordRPCLatency(i.providerName, "ethclient", "PendingNonceAt", time.Since(start))
+	return nonce, err
+}
+
+func (i *InstrumentedEthClient) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) {
+	start := time.Now()
+	receipt, err := i.c.TransactionReceipt(ctx, txHash)
+	if err != nil {
+		if !i.IgnorableErrors(err) {
+			metrics.RecordError(i.providerName, "ethclient.TransactionReceipt")
+		}
+		return nil, err
+	}
+	metrics.RecordRPCLatency(i.providerName, "ethclient", "TransactionReceipt", time.Since(start))
+	return receipt, err
+}
+
+func (i *InstrumentedEthClient) SendTransaction(ctx context.Context, tx *types.Transaction) error {
+	start := time.Now()
+	err := i.c.SendTransaction(ctx, tx)
+	if err != nil {
+		if !i.IgnorableErrors(err) {
+			metrics.RecordError(i.providerName, "ethclient.SendTransaction")
+		}
+		return err
+	}
+	metrics.RecordRPCLatency(i.providerName, "ethclient", "SendTransaction", time.Since(start))
+	return err
+}
+
+func (i *InstrumentedEthClient) IgnorableErrors(err error) bool {
+	msg := err.Error()
+	// we dont use errors.Is because eth client actually uses errors.New,
+	// therefore creating an incomparable instance :(
+	return msg == ethereum.NotFound.Error() ||
+		msg == txpool.ErrAlreadyKnown.Error() ||
+		msg == core.ErrNonceTooLow.Error()
+}

op-ufm/pkg/metrics/clients/signer.go

+package clients
+
+import (
+	"context"
+	"math/big"
+	"op-ufm/pkg/metrics"
+	"time"
+
+	optls "github.com/ethereum-optimism/optimism/op-service/tls"
+	signer "github.com/ethereum-optimism/optimism/op-signer/client"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/log"
+)
+
+type InstrumentedSignerClient struct {
+	c            *signer.SignerClient
+	providerName string
+}
+
+func NewSignerClient(providerName string, logger log.Logger, endpoint string, tlsConfig optls.CLIConfig) (*InstrumentedSignerClient, error) {
+	start := time.Now()
+	c, err := signer.NewSignerClient(logger, endpoint, tlsConfig)
+	if err != nil {
+		metrics.RecordError(providerName, "signer.NewSignerClient")
+		return nil, err
+	}
+	metrics.RecordRPCLatency(providerName, "signer", "NewSignerClient", time.Since(start))
+	return &InstrumentedSignerClient{c: c, providerName: providerName}, nil
+}
+
+func (i *InstrumentedSignerClient) SignTransaction(ctx context.Context, chainId *big.Int, tx *types.Transaction) (*types.Transaction, error) {
+	start := time.Now()
+	tx, err := i.c.SignTransaction(ctx, chainId, tx)
+	if err != nil {
+		metrics.RecordError(i.providerName, "signer.SignTransaction")
+		return nil, err
+	}
+	metrics.RecordRPCLatency(i.providerName, "signer", "SignTransaction", time.Since(start))
+	return tx, err
+}

op-ufm/pkg/metrics/metrics.go

+package metrics
+
+import (
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+const (
+	MetricsNamespace = "ufm"
+)
+
+var (
+	errorsTotal = promauto.NewCounterVec(prometheus.CounterOpts{
+		Namespace: MetricsNamespace,
+		Name:      "errors_total",
+		Help:      "Count of errors.",
+	}, []string{
+		"provider",
+		"error",
+	})
+
+	rpcLatency = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "rpc_latency",
+		Help:      "RPC latency per provider, client and method (ms)",
+	}, []string{
+		"provider",
+		"client",
+		"method",
+	})
+
+	roundTripLatency = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "roundtrip_latency",
+		Help:      "Round trip latency per provider (ms)",
+	}, []string{
+		"provider",
+	})
+
+	gasUsed = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "gas_used",
+		Help:      "Gas used per provider",
+	}, []string{
+		"provider",
+	})
+
+	firstSeenLatency = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "first_seen_latency",
+		Help:      "First seen latency latency per provider (ms)",
+	}, []string{
+		"provider_source",
+		"provider_seen",
+	})
+
+	providerToProviderLatency = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "provider_to_provider_latency",
+		Help:      "Provider to provider latency (ms)",
+	}, []string{
+		"provider_source",
+		"provider_seen",
+	})
+
+	networkTransactionsInFlight = promauto.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: MetricsNamespace,
+		Name:      "transactions_inflight",
+		Help:      "Transactions in flight, per network",
+	}, []string{
+		"network",
+	})
+)
+
+func RecordError(provider string, errorLabel string) {
+	errorsTotal.WithLabelValues(provider, errorLabel).Inc()
+}
+
+func RecordRPCLatency(provider string, client string, method string, latency time.Duration) {
+	rpcLatency.WithLabelValues(provider, client, method).Set(float64(latency.Milliseconds()))
+}
+
+func RecordRoundTripLatency(provider string, latency time.Duration) {
+	roundTripLatency.WithLabelValues(provider).Set(float64(latency.Milliseconds()))
+}
+
+func RecordGasUsed(provider string, val uint64) {
+	gasUsed.WithLabelValues(provider).Set(float64(val))
+}
+
+func RecordFirstSeenLatency(provider_source string, provider_seen string, latency time.Duration) {
+	firstSeenLatency.WithLabelValues(provider_source, provider_seen).Set(float64(latency.Milliseconds()))
+}
+
+func RecordProviderToProviderLatency(provider_source string, provider_seen string, latency time.Duration) {
+	firstSeenLatency.WithLabelValues(provider_source, provider_seen).Set(float64(latency.Milliseconds()))
+}
+
+func RecordTransactionsInFlight(network string, count int) {
+	networkTransactionsInFlight.WithLabelValues(network).Set(float64(count))
+}

op-ufm/pkg/provider/common.go

-package provider
-
-import (
-	"context"
-
-	"github.com/ethereum/go-ethereum/ethclient"
-)
-
-func (p *Provider) dial(ctx context.Context) (*ethclient.Client, error) {
-	return ethclient.Dial(p.config.URL)
-}

op-ufm/pkg/provider/heartbeat.go

@@ -2,6 +2,8 @@ package provider
 
 import (
 	"context"
+	"op-ufm/pkg/metrics"
+	"op-ufm/pkg/metrics/clients"
 	"time"
 
 	"github.com/ethereum/go-ethereum"
@@ -11,43 +13,69 @@ import (
 
 // Heartbeat polls for expected in-flight transactions
 func (p *Provider) Heartbeat(ctx context.Context) {
-	log.Debug("heartbeat", "provider", p.name)
+	log.Debug("heartbeat", "provider", p.name, "inflight", len(p.txPool.Transactions))
 
-	if len(p.txPool.Transactions) == 0 {
-		log.Debug("no in-flight txs", "provider", p.name)
+	metrics.RecordTransactionsInFlight(p.config.Network, len(p.txPool.Transactions))
+
+	// let's exclude transactions already seen by this provider, or originated by it
+	expectedTransactions := make([]*TransactionState, 0, len(p.txPool.Transactions))
+	alreadySeen := 0
+	for _, st := range p.txPool.Transactions {
+		if st.ProviderSentTo == p.name {
+			continue
+		}
+		if _, exist := st.SeenBy[p.name]; exist {
+			alreadySeen++
+			continue
+		}
+		expectedTransactions = append(expectedTransactions, st)
+	}
+
+	if len(expectedTransactions) == 0 {
+		log.Debug("no expected txs", "count", len(p.txPool.Transactions), "provider", p.name, "alreadySeen", alreadySeen)
 		return
 	}
 
-	ethClient, err := p.dial(ctx)
+	client, err := clients.Dial(p.name, p.config.URL)
 	if err != nil {
 		log.Error("cant dial to provider", "provider", p.name, "url", p.config.URL, "err", err)
 	}
 
-	log.Debug("checking in-flight tx", "count", len(p.txPool.Transactions), "provider", p.name)
-	for hash, st := range p.txPool.Transactions {
-		log.Debug(hash, "st", st)
+	log.Debug("checking in-flight tx", "count", len(p.txPool.Transactions), "provider", p.name, "alreadySeen", alreadySeen)
+	for _, st := range expectedTransactions {
+		hash := st.Hash.Hex()
 
-		_, isPending, err := ethClient.TransactionByHash(ctx, st.Hash)
+		_, isPending, err := client.TransactionByHash(ctx, st.Hash)
 		if err != nil && !errors.Is(err, ethereum.NotFound) {
-			log.Error("cant check transaction", "provider", p.name, "url", p.config.URL, "err", err)
+			log.Error("cant check transaction", "provider", p.name, "hash", hash, "url", p.config.URL, "err", err)
 			continue
 		}
 
 		log.Debug("got transaction", "provider", p.name, "hash", hash, "isPending", isPending)
+
+		// mark transaction as seen by this provider
 		st.M.Lock()
 		if st.FirstSeen.IsZero() {
 			st.FirstSeen = time.Now()
+			firstSeenLatency := time.Since(st.SentAt)
+			metrics.RecordFirstSeenLatency(st.ProviderSentTo, p.name, time.Since(st.SentAt))
+			log.Info("transaction first seen",
+				"hash", hash,
+				"firstSeenLatency", firstSeenLatency,
+				"provider_source", st.ProviderSentTo,
+				"provider_seen", p.name)
 		}
 		if _, exist := st.SeenBy[p.name]; !exist {
 			st.SeenBy[p.name] = time.Now()
+			metrics.RecordProviderToProviderLatency(st.ProviderSentTo, p.name, time.Since(st.SentAt))
 		}
 		st.M.Unlock()
 
+		// check if transaction have been seen by all providers
 		p.txPool.M.Lock()
-		// every provider has seen this transaction
 		if len(st.SeenBy) == p.txPool.Expected {
-			log.Debug("transaction seen by all", "hash", hash)
-			delete(p.txPool.Transactions, hash)
+			log.Debug("transaction seen by all", "hash", hash, "expected", p.txPool.Expected, "seenBy", len(st.SeenBy))
+			delete(p.txPool.Transactions, st.Hash.Hex())
 		}
 		p.txPool.M.Unlock()
 	}

op-ufm/pkg/provider/provider.go

@@ -39,7 +39,7 @@ func (p *Provider) Start(ctx context.Context) {
 	p.cancelFunc = cancelFunc
 	schedule(providerCtx, time.Duration(p.config.ReadInterval), p.Heartbeat)
 	if !p.config.ReadOnly {
-		schedule(providerCtx, time.Duration(p.config.SendInterval), p.Roundtrip)
+		schedule(providerCtx, time.Duration(p.config.SendInterval), p.RoundTrip)
 	}
 }
 
@@ -49,6 +49,14 @@ func (p *Provider) Shutdown() {
 	}
 }
 
+func (p *Provider) Name() string {
+	return p.name
+}
+
+func (p *Provider) URL() string {
+	return p.config.URL
+}
+
 func schedule(ctx context.Context, interval time.Duration, handler func(ctx context.Context)) {
 	go func() {
 		for {

op-ufm/pkg/provider/roundtrip.go

@@ -2,80 +2,116 @@ package provider
 
 import (
 	"context"
+	"op-ufm/pkg/metrics"
+	iclients "op-ufm/pkg/metrics/clients"
 	"time"
 
 	"github.com/ethereum-optimism/optimism/op-service/tls"
-	signer "github.com/ethereum-optimism/optimism/op-signer/client"
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/txpool"
 	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/ethereum/go-ethereum/ethclient"
 	"github.com/pkg/errors"
 
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 )
 
-// Roundtrip send a new transaction to measure round trip latency
-func (p *Provider) Roundtrip(ctx context.Context) {
+// RoundTrip send a new transaction to measure round trip latency
+func (p *Provider) RoundTrip(ctx context.Context) {
 	log.Debug("roundtrip", "provider", p.name)
 
-	ethClient, err := p.dial(ctx)
+	client, err := iclients.Dial(p.name, p.config.URL)
 	if err != nil {
 		log.Error("cant dial to provider", "provider", p.name, "url", p.config.URL, "err", err)
+		return
 	}
 
-	nonce, err := p.nonce(ctx, ethClient)
+	nonce, err := client.PendingNonceAt(ctx, p.walletConfig.Address)
 	if err != nil {
 		log.Error("cant get nounce", "provider", p.name, "err", err)
+		return
 	}
 
+	txHash := common.Hash{}
+	attempt := 0
+	startedAt := time.Now()
+	for {
 		tx := p.createTx(nonce)
+		txHash = tx.Hash()
 
 		signedTx, err := p.sign(ctx, tx)
 		if err != nil {
-		log.Error("cant sign tx", "tx", tx, "err", err)
+			log.Error("cant sign tx", "provider", p.name, "tx", tx, "err", err)
+			return
 		}
 
-	err = ethClient.SendTransaction(ctx, signedTx)
+		txHash = signedTx.Hash()
+
+		err = client.SendTransaction(ctx, signedTx)
 		if err != nil {
+			if err.Error() == txpool.ErrAlreadyKnown.Error() || err.Error() == core.ErrNonceTooLow.Error() {
+				if time.Since(startedAt) >= time.Duration(p.config.SendTransactionRetryTimeout) {
+					log.Error("send transaction timed out (known already)", "provider", p.name, "hash", txHash.Hex(), "elapsed", time.Since(startedAt), "attempt", attempt, "nonce", nonce)
+					metrics.RecordError(p.name, "ethclient.SendTransaction.nonce")
+					return
+				}
+				log.Warn("tx already known, incrementing nonce and trying again", "provider", p.name, "nonce", nonce)
+				time.Sleep(time.Duration(p.config.SendTransactionRetryInterval))
+				nonce++
+				attempt++
+				if attempt%10 == 0 {
+					log.Debug("retrying send transaction...", "provider", p.name, "attempt", attempt, "nonce", nonce, "elapsed", time.Since(startedAt))
+				}
+			} else {
 				log.Error("cant send transaction", "provider", p.name, "err", err)
+				return
+			}
+		} else {
+			break
+		}
 	}
-	txHash := signedTx.Hash()
-	log.Info("transaction sent", "hash", txHash.Hex())
+
+	log.Info("transaction sent", "provider", p.name, "hash", txHash.Hex(), "nonce", nonce)
 
 	// add to pool
 	sentAt := time.Now()
 	p.txPool.M.Lock()
 	p.txPool.Transactions[txHash.Hex()] = &TransactionState{
 		Hash:           txHash,
+		ProviderSentTo: p.name,
 		SentAt:         sentAt,
 		SeenBy:         make(map[string]time.Time),
 	}
 	p.txPool.M.Unlock()
 
 	var receipt *types.Receipt
-	attempt := 0
+	attempt = 0
 	for receipt == nil {
 		if time.Since(sentAt) >= time.Duration(p.config.ReceiptRetrievalTimeout) {
 			log.Error("receipt retrieval timed out", "provider", p.name, "hash", "elapsed", time.Since(sentAt))
-			break
+			return
 		}
 		time.Sleep(time.Duration(p.config.ReceiptRetrievalInterval))
 		if attempt%10 == 0 {
-			log.Debug("checking for receipt...", "attempt", attempt, "elapsed", time.Since(sentAt))
+			log.Debug("checking for receipt...", "provider", p.name, "attempt", attempt, "elapsed", time.Since(sentAt))
 		}
-		receipt, err = ethClient.TransactionReceipt(ctx, txHash)
+		receipt, err = client.TransactionReceipt(ctx, txHash)
 		if err != nil && !errors.Is(err, ethereum.NotFound) {
 			log.Error("cant get receipt for transaction", "provider", p.name, "hash", txHash.Hex(), "err", err)
-			break
+			return
 		}
 		attempt++
 	}
 	roundtrip := time.Since(sentAt)
+	metrics.RecordRoundTripLatency(p.name, roundtrip)
+
+	metrics.RecordGasUsed(p.name, receipt.GasUsed)
 
 	log.Info("got transaction receipt", "hash", txHash.Hex(),
 		"roundtrip", roundtrip,
+		"provider", p.name,
 		"blockNumber", receipt.BlockNumber,
 		"blockHash", receipt.BlockHash,
 		"gasUsed", receipt.GasUsed)
@@ -94,7 +130,6 @@ func (p *Provider) createTx(nonce uint64) *types.Transaction {
 		Value:     &p.walletConfig.TxValue,
 		Data:      data,
 	})
-	// log.Debug("tx", "tx", tx)
 	return tx
 }
 
@@ -112,7 +147,7 @@ func (p *Provider) sign(ctx context.Context, tx *types.Transaction) (*types.Tran
 			TLSCert:   p.signerConfig.TLSCert,
 			TLSKey:    p.signerConfig.TLSKey,
 		}
-		client, err := signer.NewSignerClient(log.Root(), p.signerConfig.URL, tlsConfig)
+		client, err := iclients.NewSignerClient(p.name, log.Root(), p.signerConfig.URL, tlsConfig)
 		log.Debug("signerclient", "client", client, "err", err)
 		if err != nil {
 			return nil, err
@@ -132,8 +167,3 @@ func (p *Provider) sign(ctx context.Context, tx *types.Transaction) (*types.Tran
 		return nil, errors.New("invalid signer method")
 	}
 }
-
-func (p *Provider) nonce(ctx context.Context, client *ethclient.Client) (uint64, error) {
-	fromAddress := common.HexToAddress(p.walletConfig.Address)
-	return client.PendingNonceAt(ctx, fromAddress)
-}

op-ufm/pkg/provider/tx_pool.go

@@ -25,6 +25,7 @@ type TransactionState struct {
 	M sync.Mutex
 
 	SentAt         time.Time
+	ProviderSentTo string
 
 	FirstSeen time.Time
 

op-ufm/pkg/service/healthz.go

@@ -5,9 +5,6 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/ethereum/go-ethereum/log"
-	"github.com/pkg/errors"
-
 	"github.com/gorilla/mux"
 	"github.com/rs/cors"
 )
@@ -17,8 +14,7 @@ type Healthz struct {
 	server *http.Server
 }
 
-func (h *Healthz) Start(ctx context.Context, host string, port int) {
-	go func() {
+func (h *Healthz) Start(ctx context.Context, host string, port int) error {
 	hdlr := mux.NewRouter()
 	hdlr.HandleFunc("/healthz", h.Handle).Methods("GET")
 	addr := fmt.Sprintf("%s:%d", host, port)
@@ -31,11 +27,7 @@ func (h *Healthz) Start(ctx context.Context, host string, port int) {
 	}
 	h.server = server
 	h.ctx = ctx
-		err := h.server.ListenAndServe()
-		if err != nil && !errors.Is(err, http.ErrServerClosed) {
-			log.Crit("error starting healthz server", "err", err)
-		}
-	}()
+	return h.server.ListenAndServe()
 }
 
 func (h *Healthz) Shutdown() error {

op-ufm/pkg/service/service.go

@@ -2,10 +2,13 @@ package service
 
 import (
 	"context"
+	"fmt"
+	"net/http"
 	"op-ufm/pkg/config"
 	"op-ufm/pkg/provider"
 
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 type Service struct {
@@ -26,8 +29,23 @@ func New(cfg *config.Config) *Service {
 func (s *Service) Start(ctx context.Context) {
 	log.Info("service starting")
 	if s.Config.Healthz.Enabled {
-		s.Healthz.Start(ctx, s.Config.Healthz.Host, s.Config.Healthz.Port)
-		log.Info("healthz started")
+		addr := fmt.Sprintf("%s:%d", s.Config.Healthz.Host, s.Config.Healthz.Port)
+		log.Info("starting healthz server", "addr", addr)
+		go func() {
+			if err := s.Healthz.Start(ctx, s.Config.Healthz.Host, s.Config.Healthz.Port); err != nil {
+				log.Error("error starting healthz server", "err", err)
+			}
+		}()
+	}
+
+	if s.Config.Metrics.Enabled {
+		addr := fmt.Sprintf("%s:%d", s.Config.Metrics.Host, s.Config.Metrics.Port)
+		log.Info("starting metrics server", "addr", addr)
+		go func() {
+			if err := http.ListenAndServe(addr, promhttp.Handler()); err != nil {
+				log.Error("error starting metrics server", "err", err)
+			}
+		}()
 	}
 
 	// map networks to its providers
@@ -46,7 +64,9 @@ func (s *Service) Start(ctx context.Context) {
 		}
 		(*txpool)[name] = &provider.NetworkTransactionPool{}
 		(*txpool)[name].Transactions = make(map[string]*provider.TransactionState)
-		(*txpool)[name].Expected = len(providers)
+		// set expected number of providers for this network
+		// -1 since we don't wait for acking from the same provider
+		(*txpool)[name].Expected = len(providers) - 1
 	}
 
 	for name, providerConfig := range s.Config.Providers {
@@ -62,6 +82,7 @@ func (s *Service) Start(ctx context.Context) {
 		s.Providers[name].Start(ctx)
 		log.Info("provider started", "provider", name)
 	}
+
 	log.Info("service started")
 }