From 2cdce538f45244c29dc409e4bac56f42dde10921 Mon Sep 17 00:00:00 2001
From: Lee Bousfield <ljbousfield@gmail.com>
Date: Wed, 18 Sep 2024 14:02:39 -0500
Subject: [PATCH] Improve stability of getNodeCreationBlock for L3s

---
 staker/rollup_watcher.go | 33 +++++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/staker/rollup_watcher.go b/staker/rollup_watcher.go
index 5ef28a49dc..cd7e5d059d 100644
--- a/staker/rollup_watcher.go
+++ b/staker/rollup_watcher.go
@@ -4,16 +4,19 @@
 package staker
 
 import (
+	"bytes"
 	"context"
 	"encoding/binary"
 	"errors"
 	"fmt"
 	"math/big"
+	"strings"
 	"sync/atomic"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/offchainlabs/nitro/arbutil"
 	"github.com/offchainlabs/nitro/solgen/go/rollupgen"
 	"github.com/offchainlabs/nitro/util/headerreader"
@@ -51,6 +54,7 @@ type RollupWatcher struct {
 	client              arbutil.L1Interface
 	baseCallOpts        bind.CallOpts
 	unSupportedL3Method atomic.Bool
+	supportedL3Method   atomic.Bool
 }
 
 func NewRollupWatcher(address common.Address, client arbutil.L1Interface, callOpts bind.CallOpts) (*RollupWatcher, error) {
@@ -73,15 +77,40 @@ func (r *RollupWatcher) getCallOpts(ctx context.Context) *bind.CallOpts {
 	return &opts
 }
 
+const noNodeErr string = "NO_NODE"
+
+func looksLikeNoNodeError(err error) bool {
+	if err == nil {
+		return false
+	}
+	if strings.Contains(err.Error(), noNodeErr) {
+		return true
+	}
+	errWithData, ok := err.(rpc.DataError)
+	if !ok {
+		return false
+	}
+	dataString, ok := errWithData.ErrorData().(string)
+	if !ok {
+		return false
+	}
+	data := common.FromHex(dataString)
+	return bytes.Contains(data, []byte(noNodeErr))
+}
+
 func (r *RollupWatcher) getNodeCreationBlock(ctx context.Context, nodeNum uint64) (*big.Int, error) {
 	callOpts := r.getCallOpts(ctx)
 	if !r.unSupportedL3Method.Load() {
 		createdAtBlock, err := r.GetNodeCreationBlockForLogLookup(callOpts, nodeNum)
 		if err == nil {
+			r.supportedL3Method.Store(true)
 			return createdAtBlock, nil
 		}
-		log.Trace("failed to call getNodeCreationBlockForLogLookup, falling back on node CreatedAtBlock field", "err", err)
-		if headerreader.ExecutionRevertedRegexp.MatchString(err.Error()) {
+		if headerreader.ExecutionRevertedRegexp.MatchString(err.Error()) && !looksLikeNoNodeError(err) {
+			if r.supportedL3Method.Load() {
+				return nil, fmt.Errorf("getNodeCreationBlockForLogLookup failed despite previously succeeding: %w", err)
+			}
+			log.Trace("failed to call getNodeCreationBlockForLogLookup, falling back on node CreatedAtBlock field", "err", err)
 			r.unSupportedL3Method.Store(true)
 		} else {
 			return nil, err