// VulcanizeDB // Copyright © 2019 Vulcanize // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Affero General Public License for more details. // You should have received a copy of the GNU Affero General Public License // along with this program. If not, see . package eth import ( "fmt" "github.com/ethereum/go-ethereum/statediff/trie_helpers" sdtypes "github.com/ethereum/go-ethereum/statediff/types" "github.com/jmoiron/sqlx" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/rlp" "github.com/lib/pq" ) const ( // node type removed value. // https://github.com/vulcanize/go-ethereum/blob/271f4d01e7e2767ffd8e0cd469bf545be96f2a84/statediff/indexer/helpers.go#L34 removedNode = 3 RetrieveHeadersByHashesPgStr = `SELECT cid, data FROM eth.header_cids INNER JOIN public.blocks ON ( header_cids.mh_key = blocks.key AND header_cids.block_number = blocks.block_number ) WHERE block_hash = ANY($1::VARCHAR(66)[])` RetrieveHeadersByBlockNumberPgStr = `SELECT cid, data FROM eth.header_cids INNER JOIN public.blocks ON ( header_cids.mh_key = blocks.key AND header_cids.block_number = blocks.block_number ) WHERE block_number = $1` RetrieveHeaderByHashPgStr = `SELECT cid, data FROM eth.header_cids INNER JOIN public.blocks ON ( header_cids.mh_key = blocks.key AND header_cids.block_number = blocks.block_number ) WHERE block_hash = $1` RetrieveUnclesByHashesPgStr = `SELECT cid, data FROM eth.uncle_cids INNER JOIN public.blocks ON ( uncle_cids.mh_key = blocks.key AND uncle_cids.block_number = blocks.block_number ) WHERE block_hash = ANY($1::VARCHAR(66)[])` RetrieveUnclesByBlockHashPgStr = `SELECT uncle_cids.cid, data FROM eth.uncle_cids INNER JOIN eth.header_cids ON ( uncle_cids.header_id = header_cids.block_hash AND uncle_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( uncle_cids.mh_key = blocks.key AND uncle_cids.block_number = blocks.block_number ) WHERE block_hash = $1` RetrieveUnclesByBlockNumberPgStr = `SELECT uncle_cids.cid, data FROM eth.uncle_cids INNER JOIN eth.header_cids ON ( uncle_cids.header_id = header_cids.block_hash AND uncle_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( uncle_cids.mh_key = blocks.key AND uncle_cids.block_number = blocks.block_number ) WHERE block_number = $1` RetrieveUncleByHashPgStr = `SELECT cid, data FROM eth.uncle_cids INNER JOIN public.blocks ON ( uncle_cids.mh_key = blocks.key AND uncle_cids.block_number = blocks.block_number ) WHERE block_hash = $1` RetrieveTransactionsByHashesPgStr = `SELECT cid, data FROM eth.transaction_cids INNER JOIN public.blocks ON ( transaction_cids.mh_key = blocks.key AND transaction_cids.block_number = blocks.block_number ) WHERE tx_hash = ANY($1::VARCHAR(66)[])` RetrieveTransactionsByBlockHashPgStr = `SELECT transaction_cids.cid, data FROM eth.transaction_cids INNER JOIN eth.header_cids ON ( transaction_cids.header_id = header_cids.block_hash AND transaction_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( transaction_cids.mh_key = blocks.key AND transaction_cids.block_number = blocks.block_number ) WHERE block_hash = $1 ORDER BY eth.transaction_cids.index ASC` RetrieveTransactionsByBlockNumberPgStr = `SELECT transaction_cids.cid, data FROM eth.transaction_cids INNER JOIN eth.header_cids ON ( transaction_cids.header_id = header_cids.block_hash AND transaction_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( transaction_cids.mh_key = blocks.key AND transaction_cids.block_number = blocks.block_number ) WHERE block_number = $1 ORDER BY eth.transaction_cids.index ASC` RetrieveTransactionByHashPgStr = `SELECT cid, data FROM eth.transaction_cids INNER JOIN public.blocks ON ( transaction_cids.mh_key = blocks.key AND transaction_cids.block_number = blocks.block_number ) WHERE tx_hash = $1` RetrieveReceiptsByTxHashesPgStr = `SELECT receipt_cids.leaf_cid, data FROM eth.receipt_cids INNER JOIN eth.transaction_cids ON ( receipt_cids.tx_id = transaction_cids.tx_hash AND receipt_cids.block_number = transaction_cids.block_number ) INNER JOIN public.blocks ON ( receipt_cids.leaf_mh_key = blocks.key AND receipt_cids.block_number = blocks.block_number ) WHERE tx_hash = ANY($1::VARCHAR(66)[])` RetrieveReceiptsByBlockHashPgStr = `SELECT receipt_cids.leaf_cid, data, eth.transaction_cids.tx_hash FROM eth.receipt_cids INNER JOIN eth.transaction_cids ON ( receipt_cids.tx_id = transaction_cids.tx_hash AND receipt_cids.block_number = transaction_cids.block_number ) INNER JOIN eth.header_cids ON ( transaction_cids.header_id = header_cids.block_hash AND transaction_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( receipt_cids.leaf_mh_key = blocks.key AND receipt_cids.block_number = blocks.block_number ) WHERE block_hash = $1 ORDER BY eth.transaction_cids.index ASC` RetrieveReceiptsByBlockNumberPgStr = `SELECT receipt_cids.leaf_cid, data FROM eth.receipt_cids INNER JOIN eth.transaction_cids ON ( receipt_cids.tx_id = transaction_cids.tx_hash AND receipt_cids.block_number = transaction_cids.block_number ) INNER JOIN eth.header_cids ON ( transaction_cids.header_id = header_cids.block_hash AND transaction_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( receipt_cids.leaf_mh_key = blocks.key AND receipt_cids.block_number = blocks.block_number ) WHERE block_number = $1 ORDER BY eth.transaction_cids.index ASC` RetrieveReceiptByTxHashPgStr = `SELECT receipt_cids.leaf_cid, data FROM eth.receipt_cids INNER JOIN eth.transaction_cids ON ( receipt_cids.tx_id = transaction_cids.tx_hash AND receipt_cids.block_number = transaction_cids.block_number ) INNER JOIN public.blocks ON ( receipt_cids.leaf_mh_key = blocks.key AND receipt_cids.block_number = blocks.block_number ) WHERE tx_hash = $1` RetrieveAccountByLeafKeyAndBlockHashPgStr = `SELECT state_cids.cid, data, state_cids.node_type FROM eth.state_cids INNER JOIN eth.header_cids ON ( state_cids.header_id = header_cids.block_hash AND state_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( state_cids.mh_key = blocks.key AND state_cids.block_number = blocks.block_number ) WHERE state_leaf_key = $1 AND block_number <= (SELECT block_number FROM eth.header_cids WHERE block_hash = $2) AND header_cids.block_hash = (SELECT canonical_header_hash(block_number)) ORDER BY block_number DESC LIMIT 1` RetrieveAccountByLeafKeyAndBlockNumberPgStr = `SELECT state_cids.cid, data, state_cids.node_type FROM eth.state_cids INNER JOIN eth.header_cids ON ( state_cids.header_id = header_cids.block_hash AND state_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( state_cids.mh_key = blocks.key AND state_cids.block_number = blocks.block_number ) WHERE state_leaf_key = $1 AND block_number <= $2 ORDER BY block_number DESC LIMIT 1` RetrieveStorageLeafByAddressHashAndLeafKeyAndBlockNumberPgStr = `SELECT storage_cids.cid, data, storage_cids.node_type, was_state_leaf_removed($1, $3) AS state_leaf_removed FROM eth.storage_cids INNER JOIN eth.state_cids ON ( storage_cids.header_id = state_cids.header_id AND storage_cids.state_path = state_cids.state_path AND storage_cids.block_number = state_cids.block_number ) INNER JOIN eth.header_cids ON ( state_cids.header_id = header_cids.block_hash AND state_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( storage_cids.mh_key = blocks.key AND storage_cids.block_number = blocks.block_number ) WHERE state_leaf_key = $1 AND storage_leaf_key = $2 AND block_number <= $3 ORDER BY block_number DESC LIMIT 1` RetrieveStorageLeafByAddressHashAndLeafKeyAndBlockHashPgStr = `SELECT storage_cids.cid, data, storage_cids.node_type, was_state_leaf_removed($1, $3) AS state_leaf_removed FROM eth.storage_cids INNER JOIN eth.state_cids ON ( storage_cids.header_id = state_cids.header_id AND storage_cids.state_path = state_cids.state_path AND storage_cids.block_number = state_cids.block_number ) INNER JOIN eth.header_cids ON ( state_cids.header_id = header_cids.block_hash AND state_cids.block_number = header_cids.block_number ) INNER JOIN public.blocks ON ( storage_cids.mh_key = blocks.key AND storage_cids.block_number = blocks.block_number ) WHERE state_leaf_key = $1 AND storage_leaf_key = $2 AND block_number <= (SELECT block_number FROM eth.header_cids WHERE block_hash = $3) AND header_cids.block_hash = (SELECT canonical_header_hash(block_number)) ORDER BY block_number DESC LIMIT 1` ) var EmptyNodeValue = make([]byte, common.HashLength) type rctIpldResult struct { LeafCID string `db:"leaf_cid"` Data []byte `db:"data"` TxHash string `db:"tx_hash"` } type ipldResult struct { CID string `db:"cid"` Data []byte `db:"data"` TxHash string `db:"tx_hash"` } type IPLDRetriever struct { db *sqlx.DB } func NewIPLDRetriever(db *sqlx.DB) *IPLDRetriever { return &IPLDRetriever{ db: db, } } // RetrieveHeadersByHashes returns the cids and rlp bytes for the headers corresponding to the provided block hashes func (r *IPLDRetriever) RetrieveHeadersByHashes(hashes []common.Hash) ([]string, [][]byte, error) { headerResults := make([]ipldResult, 0) hashStrs := make([]string, len(hashes)) for i, hash := range hashes { hashStrs[i] = hash.Hex() } if err := r.db.Select(&headerResults, RetrieveHeadersByHashesPgStr, pq.Array(hashStrs)); err != nil { return nil, nil, err } cids := make([]string, len(headerResults)) headers := make([][]byte, len(headerResults)) for i, res := range headerResults { cids[i] = res.CID headers[i] = res.Data } return cids, headers, nil } // RetrieveHeadersByBlockNumber returns the cids and rlp bytes for the headers corresponding to the provided block number // This can return more than one result since there can be more than one header (non-canonical headers) func (r *IPLDRetriever) RetrieveHeadersByBlockNumber(number uint64) ([]string, [][]byte, error) { headerResults := make([]ipldResult, 0) if err := r.db.Select(&headerResults, RetrieveHeadersByBlockNumberPgStr, number); err != nil { return nil, nil, err } cids := make([]string, len(headerResults)) headers := make([][]byte, len(headerResults)) for i, res := range headerResults { cids[i] = res.CID headers[i] = res.Data } return cids, headers, nil } // RetrieveHeaderByHash returns the cid and rlp bytes for the header corresponding to the provided block hash func (r *IPLDRetriever) RetrieveHeaderByHash(hash common.Hash) (string, []byte, error) { headerResult := new(ipldResult) return headerResult.CID, headerResult.Data, r.db.Get(headerResult, RetrieveHeaderByHashPgStr, hash.Hex()) } // RetrieveUnclesByHashes returns the cids and rlp bytes for the uncles corresponding to the provided uncle hashes func (r *IPLDRetriever) RetrieveUnclesByHashes(hashes []common.Hash) ([]string, [][]byte, error) { uncleResults := make([]ipldResult, 0) hashStrs := make([]string, len(hashes)) for i, hash := range hashes { hashStrs[i] = hash.Hex() } if err := r.db.Select(&uncleResults, RetrieveUnclesByHashesPgStr, pq.Array(hashStrs)); err != nil { return nil, nil, err } cids := make([]string, len(uncleResults)) uncles := make([][]byte, len(uncleResults)) for i, res := range uncleResults { cids[i] = res.CID uncles[i] = res.Data } return cids, uncles, nil } // RetrieveUnclesByBlockHash returns the cids and rlp bytes for the uncles corresponding to the provided block hash (of non-omner root block) func (r *IPLDRetriever) RetrieveUnclesByBlockHash(hash common.Hash) ([]string, [][]byte, error) { uncleResults := make([]ipldResult, 0) if err := r.db.Select(&uncleResults, RetrieveUnclesByBlockHashPgStr, hash.Hex()); err != nil { return nil, nil, err } cids := make([]string, len(uncleResults)) uncles := make([][]byte, len(uncleResults)) for i, res := range uncleResults { cids[i] = res.CID uncles[i] = res.Data } return cids, uncles, nil } // RetrieveUnclesByBlockNumber returns the cids and rlp bytes for the uncles corresponding to the provided block number (of non-omner root block) func (r *IPLDRetriever) RetrieveUnclesByBlockNumber(number uint64) ([]string, [][]byte, error) { uncleResults := make([]ipldResult, 0) if err := r.db.Select(&uncleResults, RetrieveUnclesByBlockNumberPgStr, number); err != nil { return nil, nil, err } cids := make([]string, len(uncleResults)) uncles := make([][]byte, len(uncleResults)) for i, res := range uncleResults { cids[i] = res.CID uncles[i] = res.Data } return cids, uncles, nil } // RetrieveUncleByHash returns the cid and rlp bytes for the uncle corresponding to the provided uncle hash func (r *IPLDRetriever) RetrieveUncleByHash(hash common.Hash) (string, []byte, error) { uncleResult := new(ipldResult) return uncleResult.CID, uncleResult.Data, r.db.Get(uncleResult, RetrieveUncleByHashPgStr, hash.Hex()) } // RetrieveTransactionsByHashes returns the cids and rlp bytes for the transactions corresponding to the provided tx hashes func (r *IPLDRetriever) RetrieveTransactionsByHashes(hashes []common.Hash) ([]string, [][]byte, error) { txResults := make([]ipldResult, 0) hashStrs := make([]string, len(hashes)) for i, hash := range hashes { hashStrs[i] = hash.Hex() } if err := r.db.Select(&txResults, RetrieveTransactionsByHashesPgStr, pq.Array(hashStrs)); err != nil { return nil, nil, err } cids := make([]string, len(txResults)) txs := make([][]byte, len(txResults)) for i, res := range txResults { cids[i] = res.CID txs[i] = res.Data } return cids, txs, nil } // RetrieveTransactionsByBlockHash returns the cids and rlp bytes for the transactions corresponding to the provided block hash func (r *IPLDRetriever) RetrieveTransactionsByBlockHash(hash common.Hash) ([]string, [][]byte, error) { txResults := make([]ipldResult, 0) if err := r.db.Select(&txResults, RetrieveTransactionsByBlockHashPgStr, hash.Hex()); err != nil { return nil, nil, err } cids := make([]string, len(txResults)) txs := make([][]byte, len(txResults)) for i, res := range txResults { cids[i] = res.CID txs[i] = res.Data } return cids, txs, nil } // RetrieveTransactionsByBlockNumber returns the cids and rlp bytes for the transactions corresponding to the provided block number func (r *IPLDRetriever) RetrieveTransactionsByBlockNumber(number uint64) ([]string, [][]byte, error) { txResults := make([]ipldResult, 0) if err := r.db.Select(&txResults, RetrieveTransactionsByBlockNumberPgStr, number); err != nil { return nil, nil, err } cids := make([]string, len(txResults)) txs := make([][]byte, len(txResults)) for i, res := range txResults { cids[i] = res.CID txs[i] = res.Data } return cids, txs, nil } // RetrieveTransactionByTxHash returns the cid and rlp bytes for the transaction corresponding to the provided tx hash func (r *IPLDRetriever) RetrieveTransactionByTxHash(hash common.Hash) (string, []byte, error) { txResult := new(ipldResult) return txResult.CID, txResult.Data, r.db.Get(txResult, RetrieveTransactionByHashPgStr, hash.Hex()) } // DecodeLeafNode decodes the leaf node data func DecodeLeafNode(node []byte) ([]byte, error) { var nodeElements []interface{} if err := rlp.DecodeBytes(node, &nodeElements); err != nil { return nil, err } ty, err := trie_helpers.CheckKeyType(nodeElements) if err != nil { return nil, err } if ty != sdtypes.Leaf { return nil, fmt.Errorf("expected leaf node but found %s", ty) } return nodeElements[1].([]byte), nil } // RetrieveReceiptsByTxHashes returns the cids and rlp bytes for the receipts corresponding to the provided tx hashes func (r *IPLDRetriever) RetrieveReceiptsByTxHashes(hashes []common.Hash) ([]string, [][]byte, error) { rctResults := make([]rctIpldResult, 0) hashStrs := make([]string, len(hashes)) for i, hash := range hashes { hashStrs[i] = hash.Hex() } if err := r.db.Select(&rctResults, RetrieveReceiptsByTxHashesPgStr, pq.Array(hashStrs)); err != nil { return nil, nil, err } cids := make([]string, len(rctResults)) rcts := make([][]byte, len(rctResults)) for i, res := range rctResults { cids[i] = res.LeafCID nodeVal, err := DecodeLeafNode(res.Data) if err != nil { return nil, nil, err } rcts[i] = nodeVal } return cids, rcts, nil } // RetrieveReceiptsByBlockHash returns the cids and rlp bytes for the receipts corresponding to the provided block hash. // cid returned corresponds to the leaf node data which contains the receipt. func (r *IPLDRetriever) RetrieveReceiptsByBlockHash(hash common.Hash) ([]string, [][]byte, []common.Hash, error) { rctResults := make([]rctIpldResult, 0) if err := r.db.Select(&rctResults, RetrieveReceiptsByBlockHashPgStr, hash.Hex()); err != nil { return nil, nil, nil, err } cids := make([]string, len(rctResults)) rcts := make([][]byte, len(rctResults)) txs := make([]common.Hash, len(rctResults)) for i, res := range rctResults { cids[i] = res.LeafCID nodeVal, err := DecodeLeafNode(res.Data) if err != nil { return nil, nil, nil, err } rcts[i] = nodeVal txs[i] = common.HexToHash(res.TxHash) } return cids, rcts, txs, nil } // RetrieveReceiptsByBlockNumber returns the cids and rlp bytes for the receipts corresponding to the provided block hash. // cid returned corresponds to the leaf node data which contains the receipt. func (r *IPLDRetriever) RetrieveReceiptsByBlockNumber(number uint64) ([]string, [][]byte, error) { rctResults := make([]rctIpldResult, 0) if err := r.db.Select(&rctResults, RetrieveReceiptsByBlockNumberPgStr, number); err != nil { return nil, nil, err } cids := make([]string, len(rctResults)) rcts := make([][]byte, len(rctResults)) for i, res := range rctResults { cids[i] = res.LeafCID nodeVal, err := DecodeLeafNode(res.Data) if err != nil { return nil, nil, err } rcts[i] = nodeVal } return cids, rcts, nil } // RetrieveReceiptByHash returns the cid and rlp bytes for the receipt corresponding to the provided tx hash. // cid returned corresponds to the leaf node data which contains the receipt. func (r *IPLDRetriever) RetrieveReceiptByHash(hash common.Hash) (string, []byte, error) { rctResult := new(rctIpldResult) if err := r.db.Select(&rctResult, RetrieveReceiptByTxHashPgStr, hash.Hex()); err != nil { return "", nil, err } nodeVal, err := DecodeLeafNode(rctResult.Data) if err != nil { return "", nil, err } return rctResult.LeafCID, nodeVal, nil } type nodeInfo struct { CID string `db:"cid"` Data []byte `db:"data"` NodeType int `db:"node_type"` StateLeafRemoved bool `db:"state_leaf_removed"` } // RetrieveAccountByAddressAndBlockHash returns the cid and rlp bytes for the account corresponding to the provided address and block hash // TODO: ensure this handles deleted accounts appropriately func (r *IPLDRetriever) RetrieveAccountByAddressAndBlockHash(address common.Address, hash common.Hash) (string, []byte, error) { accountResult := new(nodeInfo) leafKey := crypto.Keccak256Hash(address.Bytes()) if err := r.db.Get(accountResult, RetrieveAccountByLeafKeyAndBlockHashPgStr, leafKey.Hex(), hash.Hex()); err != nil { return "", nil, err } if accountResult.NodeType == removedNode { return "", EmptyNodeValue, nil } var i []interface{} if err := rlp.DecodeBytes(accountResult.Data, &i); err != nil { return "", nil, fmt.Errorf("error decoding state leaf node rlp: %s", err.Error()) } if len(i) != 2 { return "", nil, fmt.Errorf("eth IPLDRetriever expected state leaf node rlp to decode into two elements") } return accountResult.CID, i[1].([]byte), nil } // RetrieveAccountByAddressAndBlockNumber returns the cid and rlp bytes for the account corresponding to the provided address and block number // This can return a non-canonical account func (r *IPLDRetriever) RetrieveAccountByAddressAndBlockNumber(address common.Address, number uint64) (string, []byte, error) { accountResult := new(nodeInfo) leafKey := crypto.Keccak256Hash(address.Bytes()) if err := r.db.Get(accountResult, RetrieveAccountByLeafKeyAndBlockNumberPgStr, leafKey.Hex(), number); err != nil { return "", nil, err } if accountResult.NodeType == removedNode { return "", EmptyNodeValue, nil } var i []interface{} if err := rlp.DecodeBytes(accountResult.Data, &i); err != nil { return "", nil, fmt.Errorf("error decoding state leaf node rlp: %s", err.Error()) } if len(i) != 2 { return "", nil, fmt.Errorf("eth IPLDRetriever expected state leaf node rlp to decode into two elements") } return accountResult.CID, i[1].([]byte), nil } // RetrieveStorageAtByAddressAndStorageSlotAndBlockHash returns the cid and rlp bytes for the storage value corresponding to the provided address, storage slot, and block hash func (r *IPLDRetriever) RetrieveStorageAtByAddressAndStorageSlotAndBlockHash(address common.Address, key, hash common.Hash) (string, []byte, []byte, error) { storageResult := new(nodeInfo) stateLeafKey := crypto.Keccak256Hash(address.Bytes()) storageHash := crypto.Keccak256Hash(key.Bytes()) if err := r.db.Get(storageResult, RetrieveStorageLeafByAddressHashAndLeafKeyAndBlockHashPgStr, stateLeafKey.Hex(), storageHash.Hex(), hash.Hex()); err != nil { return "", nil, nil, err } if storageResult.StateLeafRemoved || storageResult.NodeType == removedNode { return "", EmptyNodeValue, EmptyNodeValue, nil } var i []interface{} if err := rlp.DecodeBytes(storageResult.Data, &i); err != nil { err = fmt.Errorf("error decoding storage leaf node rlp: %s", err.Error()) return "", nil, nil, err } if len(i) != 2 { return "", nil, nil, fmt.Errorf("eth IPLDRetriever expected storage leaf node rlp to decode into two elements") } return storageResult.CID, storageResult.Data, i[1].([]byte), nil } // RetrieveStorageAtByAddressAndStorageKeyAndBlockNumber returns the cid and rlp bytes for the storage value corresponding to the provided address, storage key, and block number // This can retrun a non-canonical value func (r *IPLDRetriever) RetrieveStorageAtByAddressAndStorageKeyAndBlockNumber(address common.Address, storageLeafKey common.Hash, number uint64) (string, []byte, error) { storageResult := new(nodeInfo) stateLeafKey := crypto.Keccak256Hash(address.Bytes()) if err := r.db.Get(storageResult, RetrieveStorageLeafByAddressHashAndLeafKeyAndBlockNumberPgStr, stateLeafKey.Hex(), storageLeafKey.Hex(), number); err != nil { return "", nil, err } if storageResult.StateLeafRemoved || storageResult.NodeType == removedNode { return "", EmptyNodeValue, nil } var i []interface{} if err := rlp.DecodeBytes(storageResult.Data, &i); err != nil { return "", nil, fmt.Errorf("error decoding storage leaf node rlp: %s", err.Error()) } if len(i) != 2 { return "", nil, fmt.Errorf("eth IPLDRetriever expected storage leaf node rlp to decode into two elements") } return storageResult.CID, i[1].([]byte), nil }