From b5dfeffc8490d01d08b65ca663e373bcacb57a0b Mon Sep 17 00:00:00 2001
From: Martin Kysel <code@martinkysel.com>
Date: Mon, 24 Feb 2025 16:36:11 -0500
Subject: [PATCH] Allow running without payer key (#547)

If you were to try to run the XMTP API/SYNC without providing the payer
key, the node will crash:
```
$ ./dev/run
2025-02-24T14:01:43.485-0500    INFO    replication     Version: v0.2.0-9-g1f8192f
2025-02-24T14:01:43.495-0500    INFO    replication     Successfully connected to DB    {"namespace": "xmtpd_c04b2306614f"}
2025-02-24T14:01:43.512-0500    FATAL   replication     initializing signer     {"error": "unable to parse private key: invalid length, need 256 bits"}
exit status 1
```

The blockchain publisher is only required for the payer. If we ever need
it for the node, it will have to use the node key.

I will break apart the XMTPD image and the payer image in the next few
days. But I need this to get the infra code moving.
---
 cmd/replication/main.go   | 20 --------------------
 pkg/server/server.go      | 28 +++++++++++++++++++++++++---
 pkg/server/server_test.go |  8 +-------
 3 files changed, 26 insertions(+), 30 deletions(-)

diff --git a/cmd/replication/main.go b/cmd/replication/main.go
index 5ab54207..c440c735 100644
--- a/cmd/replication/main.go
+++ b/cmd/replication/main.go
@@ -110,32 +110,12 @@ func main() {
 			logger.Fatal("starting smart contract registry", zap.Error(err))
 		}
 
-		signer, err := blockchain.NewPrivateKeySigner(
-			options.Payer.PrivateKey,
-			options.Contracts.ChainID,
-		)
-		if err != nil {
-			logger.Fatal("initializing signer", zap.Error(err))
-		}
-
-		blockchainPublisher, err := blockchain.NewBlockchainPublisher(
-			ctx,
-			logger,
-			ethclient,
-			signer,
-			options.Contracts,
-		)
-		if err != nil {
-			logger.Fatal("initializing message publisher", zap.Error(err))
-		}
-
 		s, err := server.NewReplicationServer(
 			ctx,
 			logger,
 			options,
 			chainRegistry,
 			dbInstance,
-			blockchainPublisher,
 			fmt.Sprintf("0.0.0.0:%d", options.API.Port),
 			version,
 		)
diff --git a/pkg/server/server.go b/pkg/server/server.go
index fba43689..3022b540 100644
--- a/pkg/server/server.go
+++ b/pkg/server/server.go
@@ -57,7 +57,6 @@ func NewReplicationServer(
 	options config.ServerOptions,
 	nodeRegistry registry.NodeRegistry,
 	writerDB *sql.DB,
-	blockchainPublisher blockchain.IBlockchainPublisher,
 	listenAddress string,
 	serverVersion *semver.Version,
 ) (*ReplicationServer, error) {
@@ -135,7 +134,6 @@ func NewReplicationServer(
 			options,
 			s,
 			writerDB,
-			blockchainPublisher,
 			listenAddress,
 			serverVersion,
 		)
@@ -170,7 +168,6 @@ func startAPIServer(
 	options config.ServerOptions,
 	s *ReplicationServer,
 	writerDB *sql.DB,
-	blockchainPublisher blockchain.IBlockchainPublisher,
 	listenAddress string,
 	serverVersion *semver.Version,
 ) error {
@@ -223,6 +220,31 @@ func startAPIServer(
 			if err != nil {
 				return err
 			}
+
+			signer, err := blockchain.NewPrivateKeySigner(
+				options.Payer.PrivateKey,
+				options.Contracts.ChainID,
+			)
+			if err != nil {
+				log.Fatal("initializing signer", zap.Error(err))
+			}
+
+			ethclient, err := blockchain.NewClient(ctx, options.Contracts.RpcUrl)
+			if err != nil {
+				log.Fatal("initializing blockchain client", zap.Error(err))
+			}
+
+			blockchainPublisher, err := blockchain.NewBlockchainPublisher(
+				ctx,
+				log,
+				ethclient,
+				signer,
+				options.Contracts,
+			)
+			if err != nil {
+				log.Fatal("initializing message publisher", zap.Error(err))
+			}
+
 			payerService, err := payer.NewPayerApiService(
 				ctx,
 				log,
diff --git a/pkg/server/server_test.go b/pkg/server/server_test.go
index 26a1b778..41aab841 100644
--- a/pkg/server/server_test.go
+++ b/pkg/server/server_test.go
@@ -13,7 +13,6 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/stretchr/testify/require"
 	"github.com/xmtp/xmtpd/pkg/config"
-	"github.com/xmtp/xmtpd/pkg/mocks/blockchain"
 	mocks "github.com/xmtp/xmtpd/pkg/mocks/registry"
 	"github.com/xmtp/xmtpd/pkg/proto/xmtpv4/envelopes"
 	"github.com/xmtp/xmtpd/pkg/proto/xmtpv4/message_api"
@@ -49,7 +48,6 @@ func NewTestServer(
 	privateKey *ecdsa.PrivateKey,
 ) *s.ReplicationServer {
 	log := testutils.NewLog(t)
-	messagePublisher := blockchain.NewMockIBlockchainPublisher(t)
 
 	server, err := s.NewReplicationServer(context.Background(), log, config.ServerOptions{
 		Contracts: config.ContractsOptions{
@@ -71,11 +69,7 @@ func NewTestServer(
 		Replication: config.ReplicationOptions{
 			Enable: true,
 		},
-		Payer: config.PayerOptions{
-			Enable:     true,
-			PrivateKey: hex.EncodeToString(crypto.FromECDSA(privateKey)),
-		},
-	}, registry, db, messagePublisher, fmt.Sprintf("localhost:%d", port), testutils.GetLatestVersion(t))
+	}, registry, db, fmt.Sprintf("localhost:%d", port), testutils.GetLatestVersion(t))
 	require.NoError(t, err)
 
 	return server