config: Add historical-data rpc fallback

cmd/geth/main.go

@@ -155,6 +155,7 @@ var (
 		utils.MinerNotifyFullFlag,
 		utils.IgnoreLegacyReceiptsFlag,
 		utils.RollupSequencerHTTPFlag,
+		utils.RollupHistoricalRPCFlag,
 		utils.RollupDisableTxPoolGossipFlag,
 		configFileFlag,
 	}, utils.NetworkFlags, utils.DatabasePathFlags)

cmd/utils/flags.go

@@ -889,6 +889,12 @@ var (
 		Category: flags.RollupCategory,
 	}
 
+	RollupHistoricalRPCFlag = &cli.StringFlag{
+		Name:     "rollup.historicalrpc",
+		Usage:    "RPC endpoint for historical data.",
+		Category: flags.RollupCategory,
+	}
+
 	RollupDisableTxPoolGossipFlag = &cli.BoolFlag{
 		Name:     "rollup.disabletxpoolgossip",
 		Usage:    "Disable transaction pool gossip.",
@@ -1876,6 +1882,9 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *ethconfig.Config) {
 	if ctx.IsSet(RollupSequencerHTTPFlag.Name) && !ctx.IsSet(MiningEnabledFlag.Name) {
 		cfg.RollupSequencerHTTP = ctx.String(RollupSequencerHTTPFlag.Name)
 	}
+	if ctx.IsSet(RollupHistoricalRPCFlag.Name) {
+		cfg.RollupHistoricalRPC = ctx.String(RollupHistoricalRPCFlag.Name)
+	}
 	cfg.RollupDisableTxPoolGossip = ctx.Bool(RollupDisableTxPoolGossipFlag.Name)
 	// Override any default configs for hard coded networks.
 	switch {

eth/backend.go

@@ -68,13 +68,14 @@ type Ethereum struct {
 	config *ethconfig.Config
 
 	// Handlers
-	txPool             *core.TxPool
-	blockchain         *core.BlockChain
-	handler            *handler
-	ethDialCandidates  enode.Iterator
-	snapDialCandidates enode.Iterator
-	merger             *consensus.Merger
-	seqRPCService      *rpc.Client
+	txPool               *core.TxPool
+	blockchain           *core.BlockChain
+	handler              *handler
+	ethDialCandidates    enode.Iterator
+	snapDialCandidates   enode.Iterator
+	merger               *consensus.Merger
+	seqRPCService        *rpc.Client
+	historicalRPCService *rpc.Client
 
 	// DB interfaces
 	chainDb ethdb.Database // Block chain database
@@ -270,6 +271,16 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 		eth.seqRPCService = client
 	}
 
+	if config.RollupHistoricalRPC != "" {
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		client, err := rpc.DialContext(ctx, config.RollupHistoricalRPC)
+		cancel()
+		if err != nil {
+			return nil, err
+		}
+		eth.historicalRPCService = client
+	}
+
 	// Start the RPC service
 	eth.netRPCService = ethapi.NewNetAPI(eth.p2pServer, config.NetworkId)
 
@@ -564,6 +575,9 @@ func (s *Ethereum) Stop() error {
 	if s.seqRPCService != nil {
 		s.seqRPCService.Close()
 	}
+	if s.historicalRPCService != nil {
+		s.historicalRPCService.Close()
+	}
 
 	// Clean shutdown marker as the last thing before closing db
 	s.shutdownTracker.Stop()

eth/ethconfig/config.go

@@ -216,6 +216,7 @@ type Config struct {
 	OverrideTerminalTotalDifficultyPassed *bool `toml:",omitempty"`
 
 	RollupSequencerHTTP string
+	RollupHistoricalRPC string
 
 	RollupDisableTxPoolGossip bool
 }