Add searcher mode for sending UserOperations to block builders (#94)

Author: hazim-j

.air.searcher-mode.toml

@@ -0,0 +1,37 @@
+root = "."
+testdata_dir = "testdata"
+tmp_dir = "tmp"
+
+[build]
+  args_bin = []
+  bin = ";ERC4337_BUNDLER_GIN_MODE=debug ./tmp/stackup-bundler start --mode searcher"
+  cmd = "go build -o ./tmp/stackup-bundler main.go"
+  delay = 1000
+  exclude_dir = ["assets", "tmp", "vendor", "testdata"]
+  exclude_file = []
+  exclude_regex = ["_test.go"]
+  exclude_unchanged = false
+  follow_symlink = false
+  full_bin = ""
+  include_dir = []
+  include_ext = ["go", "tpl", "tmpl", "html"]
+  kill_delay = "0s"
+  log = "build-errors.log"
+  send_interrupt = false
+  stop_on_error = true
+
+[color]
+  app = ""
+  build = "yellow"
+  main = "magenta"
+  runner = "green"
+  watcher = "cyan"
+
+[log]
+  time = false
+
+[misc]
+  clean_on_exit = false
+
+[screen]
+  clear_on_rebuild = false

.github/workflows/pipeline.yml

@@ -41,3 +41,5 @@ jobs:
 
       - name: Lint
         uses: golangci/golangci-lint-action@v3
+        with:
+          version: v1.51.0

Makefile

@@ -14,5 +14,8 @@ fetch-wallet:
 dev-private-mode:
 	air -c .air.private-mode.toml
 
+dev-searcher-mode:
+	air -c .air.searcher-mode.toml
+
 dev-reset-default-data-dir:
 	rm -rf /tmp/stackup_bundler

cmd/start.go

@@ -13,10 +13,13 @@ var startCmd = &cobra.Command{
 	Short: "Starts an instance in the specified mode",
 	Long: `The start command has the following modes:
 	
-	1. private: A JSON-RPC client and bundler backed by a private mempool.`,
+	1. private: A bundler backed by a private mempool and compatible with all EVM networks.
+	2. searcher: A bundler backed by the P2P mempool and integrated with a Block Builder API.`,
 	Run: func(cmd *cobra.Command, args []string) {
 		if viper.GetString("mode") == "private" {
 			start.PrivateMode()
+		} else if viper.GetString("mode") == "searcher" {
+			start.SearcherMode()
 		} else {
 			panic(fmt.Sprintf("Fatal flag error: \"%s\" mode not supported", viper.GetString("mode")))
 		}

go.mod

@@ -12,6 +12,7 @@ require (
 	github.com/go-logr/zerologr v1.2.2
 	github.com/go-playground/validator/v10 v10.11.1
 	github.com/google/go-cmp v0.5.9
+	github.com/metachris/flashbotsrpc v0.5.0
 	github.com/mitchellh/mapstructure v1.5.0
 	github.com/rs/zerolog v1.28.0
 	github.com/spf13/cobra v1.6.0
@@ -24,6 +25,7 @@ require (
 require (
 	github.com/StackExchange/wmi v0.0.0-20180116203802-5d049714c4a6 // indirect
 	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
+	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.2 // indirect
 	github.com/cespare/xxhash v1.1.0 // indirect
 	github.com/cespare/xxhash/v2 v2.1.2 // indirect
 	github.com/deckarep/golang-set v1.8.0 // indirect

go.sum

@@ -46,7 +46,8 @@ github.com/VictoriaMetrics/fastcache v1.6.0 h1:C/3Oi3EiBCqufydp1neRZkqcwmEiuRT9c
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/btcsuite/btcd/btcec/v2 v2.2.0 h1:fzn1qaOt32TuLjFlkzYSsBC35Q3KUjT1SwPxiMSCF5k=
 github.com/btcsuite/btcd/btcec/v2 v2.2.0/go.mod h1:U7MHm051Al6XmscBQ0BoNydpOTsFAn707034b5nY8zU=
-github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 h1:q0rUy8C/TYNBQS1+CGKw68tLOFYSNEs0TFnxxnS9+4U=
+github.com/btcsuite/btcd/chaincfg/chainhash v1.0.2 h1:KdUfX2zKommPRa+PD0sWZUyXe9w277ABlgELO7H04IM=
+github.com/btcsuite/btcd/chaincfg/chainhash v1.0.2/go.mod h1:7SFka0XMvUgj3hfZtydOrQY2mwhPclbT2snogU7SQQc=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/cespare/cp v0.1.0 h1:SE+dxFebS7Iik5LK0tsi1k9ZCxEaFX4AjQmoyA+1dJk=
 github.com/cespare/xxhash v1.1.0 h1:a6HrQnmkObjyL+Gs60czilIUGqrzKutQD6XZog3p+ko=
@@ -226,6 +227,7 @@ github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANyt
 github.com/inconshreveable/mousetrap v1.0.1 h1:U3uMjPSQEBMNp1lFxmllqCPM6P5u/Xq7Pgzkat/bFNc=
 github.com/inconshreveable/mousetrap v1.0.1/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/jackpal/go-nat-pmp v1.0.2 h1:KzKSgb7qkJvOUTqYl9/Hg/me3pWgBmERKrTGD7BdWus=
+github.com/jarcoal/httpmock v1.0.8 h1:8kI16SoO6LQKgPE7PvQuV+YuD/inwHd7fOOe2zMbo4k=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
@@ -255,6 +257,8 @@ github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27k
 github.com/mattn/go-isatty v0.0.16 h1:bq3VjFmv/sOjHtdEhmkEV4x1AJtvUvOJ2PFAZ5+peKQ=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=
+github.com/metachris/flashbotsrpc v0.5.0 h1:5OLpm6+6n4kXxeh3TZBeSj0PQWDxqUsOFwy7xertXQQ=
+github.com/metachris/flashbotsrpc v0.5.0/go.mod h1:UrS249kKA1PK27sf12M6tUxo/M4ayfFrBk7IMFY1TNw=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
@@ -332,6 +336,9 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/subosito/gotenv v1.4.1 h1:jyEFiXpy21Wm81FBN71l9VoMMV8H8jG+qIK3GCpY6Qs=
 github.com/subosito/gotenv v1.4.1/go.mod h1:ayKnFf/c6rvx/2iiLrJUk1e6plDbT3edrFNGqEflhK0=
 github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7 h1:epCh84lMvA70Z7CTTCmYQn2CKbY8j86K7/FAIr141uY=
+github.com/tidwall/gjson v1.8.1 h1:8j5EE9Hrh3l9Od1OIEDAb7IpezNA20UdRngNAj5N0WU=
+github.com/tidwall/match v1.0.3 h1:FQUVvBImDutD8wJLN6c5eMzWtjgONK9MwIBCOrUJKeE=
+github.com/tidwall/pretty v1.1.0 h1:K3hMW5epkdAVwibsQEfR/7Zj0Qgt4DxtNumTq/VloO8=
 github.com/tklauser/go-sysconf v0.3.5 h1:uu3Xl4nkLzQfXNsWn15rPc/HQCJKObbt1dKJeWp3vU4=
 github.com/tklauser/go-sysconf v0.3.5/go.mod h1:MkWzOF4RMCshBAMXuhXJs64Rte09mITnppBXY/rYEFI=
 github.com/tklauser/numcpus v0.2.2 h1:oyhllyrScuYI6g+h/zUvNXNp1wy7x8qQy3t/piefldA=

internal/config/values.go

@@ -23,6 +23,10 @@ type Values struct {
 	MaxOpsForUnstakedSender int
 	Beneficiary             string
 
+	// Searcher mode variables.
+	EthBuilderUrl     string
+	BlocksInTheFuture int
+
 	// Undocumented variables.
 	DebugMode              bool
 	GinMode                string
@@ -39,6 +43,10 @@ func envArrayToAddressSlice(s string) []common.Address {
 	return slc
 }
 
+func variableNotSetOrIsNil(env string) bool {
+	return !viper.IsSet(env) || viper.GetString(env) == ""
+}
+
 // GetValues returns config for the bundler that has been read in from env vars. See
 // https://docs.stackup.sh/docs/packages/bundler/configure for details.
 func GetValues() *Values {
@@ -49,6 +57,7 @@ func GetValues() *Values {
 	viper.SetDefault("erc4337_bundler_max_verification_gas", 1500000)
 	viper.SetDefault("erc4337_bundler_max_ops_for_unstaked_sender", 4)
 	viper.SetDefault("erc4337_bundler_debug_mode", false)
+	viper.SetDefault("erc4337_bundler_blocks_in_the_future", 25)
 	viper.SetDefault("erc4337_bundler_gin_mode", gin.ReleaseMode)
 
 	// Read in from .env file if available
@@ -73,15 +82,16 @@ func GetValues() *Values {
 	_ = viper.BindEnv("erc4337_bundler_beneficiary")
 	_ = viper.BindEnv("erc4337_bundler_max_verification_gas")
 	_ = viper.BindEnv("erc4337_bundler_max_ops_for_unstaked_sender")
+	_ = viper.BindEnv("erc4337_bundler_eth_builder_url")
+	_ = viper.BindEnv("erc4337_bundler_blocks_in_the_future")
 	_ = viper.BindEnv("erc4337_bundler_gin_mode")
 
 	// Validate required variables
-	if !viper.IsSet("erc4337_bundler_eth_client_url") ||
-		viper.GetString("erc4337_bundler_eth_client_url") == "" {
+	if variableNotSetOrIsNil("erc4337_bundler_eth_client_url") {
 		panic("Fatal config error: erc4337_bundler_eth_client_url not set")
 	}
 
-	if !viper.IsSet("erc4337_bundler_private_key") || viper.GetString("erc4337_bundler_private_key") == "" {
+	if variableNotSetOrIsNil("erc4337_bundler_private_key") {
 		panic("Fatal config error: erc4337_bundler_private_key not set")
 	}
 
@@ -93,6 +103,13 @@ func GetValues() *Values {
 		viper.SetDefault("erc4337_bundler_beneficiary", s.Address.String())
 	}
 
+	switch viper.GetString("mode") {
+	case "searcher":
+		if variableNotSetOrIsNil("erc4337_bundler_eth_builder_url") {
+			panic("Fatal config error: erc4337_bundler_eth_builder_url not set")
+		}
+	}
+
 	// Load js tracer from embedded file
 	bct, err := tracer.Load()
 	if err != nil {
@@ -108,6 +125,8 @@ func GetValues() *Values {
 	beneficiary := viper.GetString("erc4337_bundler_beneficiary")
 	maxVerificationGas := big.NewInt(int64(viper.GetInt("erc4337_bundler_max_verification_gas")))
 	maxOpsForUnstakedSender := viper.GetInt("erc4337_bundler_max_ops_for_unstaked_sender")
+	ethBuilderUrl := viper.GetString("erc4337_bundler_eth_builder_url")
+	blocksInTheFuture := viper.GetInt("erc4337_bundler_blocks_in_the_future")
 	debugMode := viper.GetBool("erc4337_bundler_debug_mode")
 	ginMode := viper.GetString("erc4337_bundler_gin_mode")
 	return &Values{
@@ -119,6 +138,8 @@ func GetValues() *Values {
 		Beneficiary:             beneficiary,
 		MaxVerificationGas:      maxVerificationGas,
 		MaxOpsForUnstakedSender: maxOpsForUnstakedSender,
+		EthBuilderUrl:           ethBuilderUrl,
+		BlocksInTheFuture:       blocksInTheFuture,
 		DebugMode:               debugMode,
 		GinMode:                 ginMode,
 		BundlerCollectorTracer:  bct,

internal/start/db.go

@@ -0,0 +1,22 @@
+package start
+
+import (
+	"time"
+
+	badger "github.com/dgraph-io/badger/v3"
+)
+
+func runDBGarbageCollection(db *badger.DB) {
+	go func(db *badger.DB) {
+		ticker := time.NewTicker(5 * time.Minute)
+		defer ticker.Stop()
+
+		for range ticker.C {
+		again:
+			err := db.RunValueLogGC(0.7)
+			if err == nil {
+				goto again
+			}
+		}
+	}(db)
+}

internal/start/private.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"log"
 	"net/http"
-	"time"
 
 	badger "github.com/dgraph-io/badger/v3"
 	"github.com/ethereum/go-ethereum/common"
@@ -25,21 +24,6 @@ import (
 	"github.com/stackup-wallet/stackup-bundler/pkg/signer"
 )
 
-func runDBGarbageCollection(db *badger.DB) {
-	go func(db *badger.DB) {
-		ticker := time.NewTicker(5 * time.Minute)
-		defer ticker.Stop()
-
-		for range ticker.C {
-		again:
-			err := db.RunValueLogGC(0.7)
-			if err == nil {
-				goto again
-			}
-		}
-	}(db)
-}
-
 func PrivateMode() {
 	conf := config.GetValues()
 

internal/start/searcher.go

@@ -0,0 +1,134 @@
+package start
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+
+	badger "github.com/dgraph-io/badger/v3"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/ethclient"
+	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/gin-contrib/cors"
+	"github.com/gin-gonic/gin"
+	"github.com/metachris/flashbotsrpc"
+	"github.com/stackup-wallet/stackup-bundler/internal/config"
+	"github.com/stackup-wallet/stackup-bundler/internal/logger"
+	"github.com/stackup-wallet/stackup-bundler/pkg/bundler"
+	"github.com/stackup-wallet/stackup-bundler/pkg/client"
+	"github.com/stackup-wallet/stackup-bundler/pkg/jsonrpc"
+	"github.com/stackup-wallet/stackup-bundler/pkg/mempool"
+	"github.com/stackup-wallet/stackup-bundler/pkg/modules/builder"
+	"github.com/stackup-wallet/stackup-bundler/pkg/modules/checks"
+	"github.com/stackup-wallet/stackup-bundler/pkg/modules/paymaster"
+	"github.com/stackup-wallet/stackup-bundler/pkg/signer"
+)
+
+func SearcherMode() {
+	conf := config.GetValues()
+
+	logr := logger.NewZeroLogr().
+		WithName("stackup_bundler").
+		WithValues("bundler_mode", "searcher")
+
+	eoa, err := signer.New(conf.PrivateKey)
+	if err != nil {
+		log.Fatal(err)
+	}
+	beneficiary := common.HexToAddress(conf.Beneficiary)
+
+	db, err := badger.Open(badger.DefaultOptions(conf.DataDirectory))
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+	runDBGarbageCollection(db)
+
+	rpc, err := rpc.Dial(conf.EthClientUrl)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	eth := ethclient.NewClient(rpc)
+
+	fb := flashbotsrpc.NewFlashbotsRPC(conf.EthBuilderUrl)
+
+	chain, err := eth.ChainID(context.Background())
+	if err != nil {
+		log.Fatal(err)
+	}
+	if !builder.CompatibleChainIDs.Contains(chain.Uint64()) {
+		log.Fatalf(
+			"error: network with chainID %d is not compatible with the Block Builder API.",
+			chain.Uint64(),
+		)
+	}
+
+	mem, err := mempool.New(db)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	check := checks.New(
+		rpc,
+		conf.MaxVerificationGas,
+		conf.MaxOpsForUnstakedSender,
+		conf.BundlerCollectorTracer,
+	)
+	// TODO: Create separate go-routine for tracking transactions sent to the block builder.
+	builder := builder.New(eoa, eth, fb, beneficiary, conf.BlocksInTheFuture)
+	paymaster := paymaster.New(db)
+
+	// Init Client
+	c := client.New(mem, chain, conf.SupportedEntryPoints)
+	c.SetGetUserOpReceiptFunc(client.GetUserOpReceiptWithEthClient(eth))
+	c.SetGetSimulateValidationFunc(client.GetSimulateValidationWithRpcClient(rpc))
+	c.SetGetCallGasEstimateFunc(client.GetCallGasEstimateWithEthClient(eth))
+	c.SetGetUserOpByHashFunc(client.GetUserOpByHashWithEthClient(eth))
+	c.UseLogger(logr)
+	c.UseModules(
+		check.ValidateOpValues(),
+		paymaster.CheckStatus(),
+		check.SimulateOp(),
+		// TODO: add p2p propagation module
+		paymaster.IncOpsSeen(),
+	)
+
+	// Init Bundler
+	b := bundler.New(mem, chain, conf.SupportedEntryPoints)
+	b.UseLogger(logr)
+	b.UseModules(
+		check.PaymasterDeposit(),
+		builder.SendUserOperation(),
+		paymaster.IncOpsIncluded(),
+	)
+	if err := b.Run(); err != nil {
+		log.Fatal(err)
+	}
+
+	// init Debug
+	var d *client.Debug
+	if conf.DebugMode {
+		d = client.NewDebug(eoa, eth, mem, b, chain, conf.SupportedEntryPoints[0], beneficiary)
+	}
+
+	// Init HTTP server
+	gin.SetMode(conf.GinMode)
+	r := gin.New()
+	if err := r.SetTrustedProxies(nil); err != nil {
+		log.Fatal(err)
+	}
+	r.Use(
+		cors.Default(),
+		logger.WithLogr(logr),
+		gin.Recovery(),
+	)
+	r.GET("/ping", func(g *gin.Context) {
+		g.Status(http.StatusOK)
+	})
+	r.POST("/", jsonrpc.Controller(client.NewRpcAdapter(c, d)))
+	if err := r.Run(fmt.Sprintf(":%d", conf.Port)); err != nil {
+		log.Fatal(err)
+	}
+}