Besu API objects

The following objects are parameters for or returned by Besu API methods.

info

This reference contains API objects that apply to both public and private networks. For private-network-specific API objects, see the private network API object reference.

Block object

Returned by eth_getBlockByHash and eth_getBlockByNumber.

Key	Type	Value
number	Quantity, Integer	Block number. null when block is pending.
hash	Data, 32 bytes	Hash of the block. null when block is pending.
parentHash	Data, 32 bytes	Hash of the parent block.
nonce	Data, 8 bytes	Hash of the generated proof of work. null when block is pending.
sha3Uncles	Data, 32 bytes	SHA3 of the uncle's data in the block.
logsBloom	Data, 256 bytes	Bloom filter for the block logs. null when block is pending.
transactionsRoot	Data, 32 bytes	Root of the transaction trie for the block.
stateRoot	Data, 32 bytes	Root of the final state trie for the block.
receiptsRoot	Data, 32 bytes	Root of the receipts trie for the block.
miner	Data, 20 bytes	Address to pay mining rewards to.
difficulty	Quantity, Integer	Difficulty for this block.
totalDifficulty	Quantity, Integer	Total difficulty of the chain until this block. This value will always be 0 for an uncle block.
extraData	Data	Extra data field for this block. The first 32 bytes is vanity data you can set using the --miner-extra-data command line option. Stores extra data when used with Clique and IBFT.
size	Quantity, Integer	Size of block in bytes.
gasLimit	Quantity	Maximum gas allowed in this block.
gasUsed	Quantity	Total gas used by all transactions in this block.
timestamp	Quantity	Unix timestamp (milliseconds) for block assembly.
transactions	Array	Array of transaction objects, or 32 byte transaction hashes depending on the specified boolean parameter.
uncles	Array	Array of uncle hashes.
baseFeePerGas	Quantity	The block's base fee per gas. This field is empty for blocks created before EIP-1559.

Fee history results object

Returned by eth_feeHistory for the requested block range. If blocks in the specified block range are not available, then only the fee history for available blocks is returned.

Key	Type	Value
oldestBlock	Quantity, Integer	Lowest number block of the returned range.
baseFeePerGas	Array	Array of block base fees per gas, including an extra block value. The extra value is the next block after the newest block in the returned range. Returns zeroes for blocks created before EIP-1559.
gasUsedRatio	Array	Array of block gas used ratios. These are calculated as the ratio of gasUsed and gasLimit.
reward	Array	Array of effective priority fee per gas data points from a single block. All zeroes are returned if the block is empty.

Filter options object

Parameter for eth_newFilter, eth_getLogs, and priv_getLogs. Used to filter logs.

Key	Type	Required/Optional	Value
fromBlock	Quantity | Tag	Optional	Integer block number or latest, pending, earliest. See block parameter. Default is latest.
toBlock	Quantity | Tag	Optional	Integer block number or latest, pending, earliest. See block parameter. Default is latest.
address	Data | Array	Optional	Contract address or array of addresses from which logs originate.
topics	Array of Data, 32 bytes each	Optional	Array of topics by which to filter logs.

eth_getLogs and priv_getLogs have an extra key.

Key	Type	Required/Optional	Value
blockHash	Data, 32 bytes	Optional.	Hash of block for which to return logs. If you specify blockHash, you cannot specify fromBlock and toBlock.

Log object

Returned by eth_getFilterChanges and priv_getLogs. Transaction receipt objects can contain an array of log objects.

Key	Type	Value
removed	Tag	true if log removed because of a chain reorganization. false if a valid log.
logIndex	Quantity, Integer	Log index position in the block. null when log is pending.
transactionIndex	Quantity, Integer	Index position of the starting transaction for the log. null when log is pending.
transactionHash	Data, 32 bytes	Hash of the starting transaction for the log. null when log is pending.
blockHash	Data, 32 bytes	Hash of the block that includes the log. null when log is pending.
blockNumber	Quantity	Number of block that includes the log. null when log is pending.
address	Data, 20 bytes	Address the log originated from.
data	Data	Non-indexed arguments of the log.
topics	Array of Data, 32 bytes each	Event signature hash and 0 to 3 indexed log arguments.

Miner data object

Returned by eth_getMinerDataByBlockHash and eth_getMinerDataByBlockNumber.

Key	Type	Value
netBlockReward	Quantity, Integer	The net block reward, in Wei, is staticBlockReward + transactionFee + uncleInclusionReward.
staticBlockReward	Quantity, Integer	The static block reward, in Wei, is preset on a hard fork.
transactionFee	Quantity, Integer	The transaction fee, in Wei, is sum of upfront cost - refund amount for all transactions.
uncleInclusionReward	Quantity, Integer	The uncle inclusion reward, in Wei, is static block reward * number of ommers/32.
uncleRewards	Map	Map of uncle block hashes and uncle miner coinbase addresses.
coinbase	Data, 20 bytes	Coinbase address.
extraData	Data	Extra data field for this block. The first 32 bytes is vanity data you can set using the --miner-extra-data command line option.
difficulty	Quantity, Integer	Difficulty of this block.
totalDifficulty	Quantity, Integer	Total difficulty of the chain until this block.

Pending transaction object

Returned by txpool_besuPendingTransactions.

Key	Type	Value
accessList	Array	(Optional) List of addresses and storage keys the transaction plans to access. Used in ACCESS_LIST transactions and may be used in EIP1559 transactions.
from	Data, 20 bytes	Address of the sender.
gas	Quantity	Gas provided by the sender.
gasPrice	Quantity	(Optional) Gas price, in Wei, provided by the sender. Not used only in EIP1559 transactions.
maxPriorityFeePerGas	Quantity, Integer	(Optional) Maximum fee, in Wei, the sender is willing to pay per gas above the base fee. Used only in EIP1559 transactions.
maxFeePerGas	Quantity, Integer	(Optional) Maximum total fee (base fee + priority fee), in Wei, the sender is willing to pay per gas. Used only in EIP1559 transactions.
hash	Data, 32 bytes	Hash of the transaction.
input	Data	Data sent with the transaction to create or invoke a contract.
nonce	Quantity	Number of transactions made by the sender before this one.
to	Data, 20 bytes	Address of the receiver. null if a contract creation transaction.
transactionType	String	Transaction type.
value	Quantity	Value transferred, in Wei.
v	Quantity	ECDSA Recovery ID.
r	Data, 32 bytes	ECDSA signature r.
s	Data, 32 bytes	ECDSA signature s.

Range object

Returned by debug_storageRangeAt.

Key	Type	Value
storage	Object	Key hash and value. Pre-image key is null if it falls outside the cache.
nextKey	Hash	Hash of next key if further storage in range. Otherwise, not included.

Structured log object

Log information returned as part of the Trace object.

Key	Type	Value
pc	Integer	Current program counter.
op	String	Current OpCode.
gas	Integer	Gas remaining.
gasCost	Integer	Cost in wei of each gas unit.
depth	Integer	Execution depth.
exceptionalHaltReasons	Array	One or more strings representing an error condition causing the EVM execution to terminate. These strings suggest that EVM execution terminated for reasons such as running out of gas or attempting to execute an unknown instruction. Generally a single exceptional halt reason returns but it's possible for more than one to occur at once.
stack	Array of 32 byte arrays	EVM execution stack before executing current operation.
memory	Array of 32 byte arrays	Memory space of the contract before executing current operation.
storage	Object	Storage entries changed by the current transaction.

Trace object

Returned by debug_traceBlock, debug_traceBlockByHash, debug_traceBlockByNumber, and debug_traceTransaction.

Key	Type	Value
gas	Integer	Gas used by the transaction.
failed	Boolean	True if transaction failed, otherwise, false.
returnValue	String	Bytes returned from transaction execution (without a 0x prefix).
structLogs	Array	Array of structured log objects.

Trace filter options object

Parameter for trace_filter. All parameters are optional.

Key	Type	Value
fromBLock	String | Tag	Trace starts at this block.
toBlock	String | Tag	Trace stops at this block.
fromAddress	String	Include only traces sent from this address.
toAddress	String	Include only traces with this destination address.
after	Quantity	The offset trace number.
count	Integer	Number of traces to display in a batch.

Transaction object

Returned by eth_getTransactionByHash, eth_getTransactionByBlockHashAndIndex, and eth_getTransactionByBlockNumberAndIndex.

Key	Type	Value
accessList	Array	(Optional) List of addresses and storage keys the transaction plans to access. Used in ACCESS_LIST transactions and may be used in EIP1559 transactions.
blockHash	Data, 32 bytes	Hash of the block containing this transaction. null when transaction is pending.
blockNumber	Quantity	Block number of the block containing this transaction. null when transaction is pending.
chainId	Quantity	Chain ID.
from	Data, 20 bytes	Address of the sender.
gas	Quantity	Gas provided by the sender.
gasPrice	Quantity	(Optional) Gas price, in Wei, provided by the sender. Used only in non-EIP1559 transactions.
maxPriorityFeePerGas	Quantity, Integer	(Optional) Maximum fee, in Wei, the sender is willing to pay per gas above the base fee. Used only in EIP1559 transactions.
maxFeePerGas	Quantity, Integer	(Optional) Maximum total fee (base fee + priority fee), in Wei, the sender is willing to pay per gas. Used only in EIP1559 transactions.
hash	Data, 32 bytes	Hash of the transaction.
input	Data	Data sent with the transaction to create or invoke a contract. For private transactions, it's a pointer to the transaction location in Tessera.
nonce	Quantity	Number of transactions made by the sender before this one.
to	Data, 20 bytes	Address of the receiver. null if a contract creation transaction.
transactionIndex	Quantity, Integer	Index position of the transaction in the block. null when transaction is pending.
transactionType	String	Transaction type.
value	Quantity	Value transferred, in Wei.
v	Quantity	ECDSA Recovery ID.
r	Data, 32 bytes	ECDSA signature r.
s	Data, 32 bytes	ECDSA signature s.

Transaction call object

Parameter for eth_call, eth_createAccessList, and eth_estimateGas.

All transaction call object parameters are optional.

Key	Type	Value
from	Data, 20 bytes	Address of the sender.
to	Data, 20 bytes	Address of the action receiver.
gas	Quantity, Integer	Gas provided by the sender. eth_call consumes zero gas, but other executions might need this parameter. eth_estimateGas ignores this value.
gasPrice	Quantity, Integer	Gas price, in Wei, provided by the sender. The default is 0. Used only in non-EIP1559 transactions.
maxPriorityFeePerGas	Quantity, Integer	Maximum fee, in Wei, the sender is willing to pay per gas above the base fee. Can be used only in EIP1559 transactions. If used, must specify maxFeePerGas.
maxFeePerGas	Quantity, Integer	Maximum total fee (base fee + priority fee), in Wei, the sender is willing to pay per gas. Can be used only in EIP1559 transactions. If used, must specify maxPriorityFeePerGas.
value	Quantity, Integer	Value transferred, in Wei.
data or input	Data	Hash of the method signature and encoded parameters. For details, see Ethereum Contract ABI.
accessList	Array	List of addresses and storage keys that the transaction plans to access. Used only in non-FRONTIER transactions.
strict	Tag	If true, checks that the from account’s ether balance is sufficient to cover the transaction and gas fee. If false, the gasPrice and baseFee are set to zero, in order to simulate a transaction without enforcing a balance check. The default is false.

Transaction receipt object

Returned by eth_getTransactionReceipt.

Key	Type	Value
blockHash	Data, 32 bytes	Hash of block containing this transaction.
blockNumber	Quantity	Block number of block containing this transaction.
contractAddress	Data, 20 bytes	Contract address created, if contract creation transaction, otherwise, null. A failed contract creation transaction still produces a contract address value.
cumulativeGasUsed	Quantity	Total amount of gas used by previous transactions in the block and this transaction.
effectiveGasPrice	Quantity	The actual value per gas deducted from the sender's account.
from	Data, 20 bytes	Address of the sender.
gasUsed	Quantity	Amount of gas used by this specific transaction.
logs	Array	Array of log objects generated by this transaction.
logsBloom	Data, 256 bytes	Bloom filter for light clients to quickly retrieve related logs.
status	Quantity	Either 0x0 (failure), 0x1 (success), or 0x2 (invalid).
to	Data, 20 bytes	Address of the receiver, if sending ether, otherwise, null.
transactionHash	Data, 32 bytes	Hash of the transaction.
transactionIndex	Quantity, Integer	Index position of transaction in the block.
transactionType	String	Transaction type.
revertReason	String	ABI-encoded string that displays the reason for reverting the transaction. Only available if revert reason is enabled.
type	Quantity	Transaction type, 0x00 for legacy transactions, 0x01 for access list types, 0x02 for dynamic fees.

note

For pre-Byzantium transactions, the transaction receipt object includes the following instead of status:

Key	Type	Value
root	Data, 32 bytes	Post-transaction state root

Transaction trace object

Returned by trace_replayBlockTransactions.

Key	Type	Value
output	Boolean	Transaction result. 1 for success and 0 for failure.
stateDiff	Object	State changes in the requested block.
trace	Array	Ordered list of calls to other contracts.
vmTrace	Object	Ordered list of EVM actions.
transactionHash	Data, 32 bytes	Hash of the replayed transaction.