batch headers by 100s

pkg/core/blockchain.go

@@ -10,6 +10,7 @@ type BlockChain interface {
 	ContractDataFetcher
 	GetBlockByNumber(blockNumber int64) (Block, error)
 	GetHeaderByNumber(blockNumber int64) (Header, error)
+	GetHeaderByNumbers(blockNumbers []int64) ([]Header, error)
 	GetLogs(contract Contract, startingBlockNumber *big.Int, endingBlockNumber *big.Int) ([]Log, error)
 	GetEthLogsWithCustomQuery(query ethereum.FilterQuery) ([]types.Log, error)
 	LastBlock() *big.Int

pkg/core/rpc_client.go

@@ -1,9 +1,13 @@
 package core
 
-import "context"
+import (
+	"context"
+	"github.com/ethereum/go-ethereum/rpc"
+)
 
 type RpcClient interface {
 	CallContext(ctx context.Context, result interface{}, method string, args ...interface{}) error
+	BatchCall(batch []rpc.BatchElem) error
 	IpcPath() string
 	SupportedModules() (map[string]string, error)
 }