Block

defaultBlock

caver.klay.defaultBlock

The default block is used for certain methods. You can override it by passing in the defaultBlock as the last parameter. The default value is "latest".

• caver.klay.getBalance()

• caver.klay.getCode()

• caver.klay.getTransactionCount()

• caver.klay.getStorageAt()

• caver.klay.call()

• new caver.klay.Contract() -> myContract.methods.myMethod().call()

Property

Default block parameters can be one of the following:

• Number: A block number

• "genesis" - String: The genesis block

• "latest" - String: The latest block (current head of the blockchain)

Default is "latest".

Example

> caver.klay.defaultBlock;
"latest"

// set the default block
> caver.klay.defaultBlock = 1000;

getBlockNumber

caver.klay.getBlockNumber([callback])

Returns the current block number.

Parameters

Name	Type	Description
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Number - The number of the most recent block.

Example

> caver.klay.getBlockNumber().then(console.log);
2744

getBlock

caver.klay.getBlock(blockHashOrBlockNumber [, returnTransactionObjects] [, callback])

Returns a block matching the block hash or block number.

Parameters

Name	Type	Description
blockHashOrBlockNumber	String | Number	The block hash or block number. Or the string "genesis", or "latest".
returnTransactionObjects	Boolean	(optional, default false) If true, the returned block will contain all transactions as objects, if false it will only contains the transaction hashes.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Object - The block object:

Name	Type	Description
blockScore	QUANTITY	Former difficulty. Always 1 in the BFT consensus engine
extraData	String	The "extra data" field of this block.
gasUsed	Number	The total used gas by all transactions in this block.
governanceData	DATA	RLP encoded governance configuration
hash	32-byte String	Hash of the block. null when it is a pending block.
logsBloom	256-byte String	The bloom filter for the logs of the block. null when it is a pending block.
number	Number	The block number. null when it is a pending block.
parentHash	32-byte String	Hash of the parent block.
receiptsRoot	32-byte DATA	The root of the receipts trie of the block.
reward	20-byte DATA	The address of the beneficiary to whom the block rewards were given.
size	Number	Integer the size of this block in bytes.
stateRoot	32-byte String	The root of the final state trie of the block.
timestamp	Number	The unix timestamp for when the block was collated.
timestampFoS	QUANTITY	The fraction of a second of the timestamp for when the block was collated.
totalBlockScore	QUANTITY	Integer of the total blockScore of the chain until this block.
transactions	Array	Array of transaction objects, or 32-byte transaction hashes depending on the returnTransactionObjects parameter.
transactionsRoot	32-byte String	The root of the transaction trie of the block.
voteData	DATA	RLP encoded governance vote of the proposer

Example

> caver.klay.getBlock(19097).then(console.log);
{ 
    blockscore: '0x1',
    extraData: '0xd7820a01846b6c617988676f312e31312e32856c696e75780000000000000000f8b3ea94715dd3ce7a285f21111715a2ba5537414d40506b9471959675eeb7c7ec1e0c74f206a9c488d7f178d4b8418e55cfb464eed804671bbee503f2dcacae9349f23aa3c42fc43349f96ef08bb07c1039541a3b768af32384c8e29ec7e673356a6b0ea4c6d88604ae8abae4303201f843b841386a3fbd09cd3a7c82c0b8fdc9ae8c3e624be5f12553dde42bed456093e40c113aa36fb7015b578611e2cd2ee979e6017b15be7d3cc645f455b32e8607c85d7100',
    gasUsed: '0x5208',
    governanceData: '0x',
    hash: '0x6ccef34eb59fab927705d344f080f449b576c0626e4aa3e20f569feb8df6e283',
    logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
    number: '0x4a99',
    parentHash: '0x3b56b598828368d86b175a78ba21845125372851154840c6b1b318da910849c2',
    receiptsRoot: '0xe38e5532717f12f769b07ea016014bd39b74fb72def4de8442114cc2728609f2',
    reward: '0x59e6931f46b091f4ecbc39e8626fc0be7d3fcdeb',
    size: '0x314',
    stateRoot: '0xc65b3e3f1c32c33c095507d6d37e2a8a5589b178b5b03a1365295908ac92c40c',
    timestamp: '0x5d11f951',
    timestampFoS: '0x0',
    totalBlockScore: '0x4a9a',
    transactions: [ '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca' ],
    transactionsRoot: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
    voteData: '0x' 
}

getBlockReceipts

caver.klay.getBlockReceipts(blockHash [, callback])

Returns a list of transaction receipts included in a block identified by the given block hash.

Parameters

Name	Type	Description
blockHash	String	Hash of a block.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Array - Receipts included in a block. If the target block contains no transaction, an empty array [] is returned.

Example

> caver.klay.getBlockReceipts('0x6ccef34eb59fab927705d344f080f449b576c0626e4aa3e20f569feb8df6e283').then(console.log);
[ 
    { 
        blockHash: '0x6ccef34eb59fab927705d344f080f449b576c0626e4aa3e20f569feb8df6e283',
        blockNumber: '0x4a99',
        contractAddress: null,
        from: '0x71959675eeb7c7ec1e0c74f206a9c488d7f178d4',
        gas: '0x493e0',
        gasPrice: '0x5d21dba00',
        gasUsed: '0x5208',
        logs: [],
        logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
        nonce: '0x2',
        senderTxHash: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
        signatures: [ 
            { 
                V: '0x4e43',
                R: '0xa857ef0676d7e65697cadeaf1654b2facd71d0b9f942d695f3972a1f7c34c25c',
                S: '0x43fba9e5c2c16511f951e27957f1279ea3c1f913b27f9fbb2a8dcb5884e37e3d'
            } 
        ],
        status: '0x1',
        to: '0xef5cd886c7f8d85fbe8023291761341acbb4da01',
        transactionHash: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
        transactionIndex: '0x0',
        type: 'TxTypeValueTransfer',
        typeInt: 8,
        value: '0xde0b6b3a7640000' 
    } 
]

> caver.klay.getBlockReceipts('0x6275712cd6ec769603f1560819ad226ea29216881c495c778ca68f0c1cd6e550').then(console.log);
[]

getBlockTransactionCount

caver.klay.getBlockTransactionCount(blockHashOrBlockNumber [, callback])

Returns the number of transaction in a given block.

Parameters

Name	Type	Description
blockHashOrBlockNumber	String | Number	The block number or hash. Or the string "genesis", or "latest".
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Number - The number of transactions in the given block.

Example

> caver.klay.getBlockTransactionCount("0x407d73d8a49eeb85d32cf465507dd71d507100c1").then(console.log);
1

getBlockWithConsensusInfo

caver.klay.getBlockWithConsensusInfo(blockHashOrBlockNumber [, callback])

Returns a block with consensus information matched by the given block hash or block number.

Parameters

Name	Type	Description
blockHashOrBlockNumber	String | Number	The block hash or block number. Or the string "genesis" or "latest".
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Object - A block object with consensus information (a proposer and a list of committee members) The block object contains:

Name	Type	Description
blockScore	QUANTITY	Former difficulty. Always 1 in the BFT consensus engine
committee	Array	Array of addresses of committee members of this block. The committee is a subset of validators participated in the consensus protocol for this block.
extraData	String	The "extra data" field of this block.
gasUsed	QUANTITY	The total used gas by all transactions in this block.
governanceData	DATA	RLP encoded governance configuration
hash	32-byte DATA	Hash of the block. null when it is a pending block.
logsBloom	256-byte String	The bloom filter for the logs of the block. null when it is a pending block.
number	QUANTITY	The block number. null when it is a pending block.
parentHash	32-byte DATA	Hash of the parent block.
proposer	20-byte DATA	The address of the block proposer.
receiptsRoot	32-byte DATA	The root of the receipts trie of the block.
reward	20-byte DATA	The address of the beneficiary to whom the block rewards were given.
size	QUANTITY	Integer the size of this block in bytes.
stateRoot	32-byte DATA	The root of the final state trie of the block.
timestamp	QUANTITY	The unix timestamp for when the block was collated.
timestampFoS	QUANTITY	The fraction of a second of the timestamp for when the block was collated.
totalBlockScore	QUANTITY	Integer of the total blockScore of the chain until this block.
transactions	Array	Array of transaction objects.
transactionsRoot	32-byte DATA	The root of the transaction trie of the block.
voteData	DATA	RLP encoded governance vote of the proposer

Examples

> caver.klay.getBlockWithConsensusInfo(19097).then(console.log);
{ 
    blockscore: '0x1',
    committee: [ 
        '0x715dd3ce7a285f21111715a2ba5537414d40506b',
        '0x71959675eeb7c7ec1e0c74f206a9c488d7f178d4' 
    ],
    extraData: '0xd7820a01846b6c617988676f312e31312e32856c696e75780000000000000000f8b3ea94715dd3ce7a285f21111715a2ba5537414d40506b9471959675eeb7c7ec1e0c74f206a9c488d7f178d4b8418e55cfb464eed804671bbee503f2dcacae9349f23aa3c42fc43349f96ef08bb07c1039541a3b768af32384c8e29ec7e673356a6b0ea4c6d88604ae8abae4303201f843b841386a3fbd09cd3a7c82c0b8fdc9ae8c3e624be5f12553dde42bed456093e40c113aa36fb7015b578611e2cd2ee979e6017b15be7d3cc645f455b32e8607c85d7100',
    gasUsed: '0x5208',
    governanceData: '0x',
    hash: '0x6ccef34eb59fab927705d344f080f449b576c0626e4aa3e20f569feb8df6e283',
    logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
    number: '0x4a99',
    parentHash: '0x3b56b598828368d86b175a78ba21845125372851154840c6b1b318da910849c2',
    proposer: '0x715dd3ce7a285f21111715a2ba5537414d40506b',
    receiptsRoot: '0xe38e5532717f12f769b07ea016014bd39b74fb72def4de8442114cc2728609f2',
    reward: '0x59e6931f46b091f4ecbc39e8626fc0be7d3fcdeb',
    size: '0x314',
    stateRoot: '0xc65b3e3f1c32c33c095507d6d37e2a8a5589b178b5b03a1365295908ac92c40c',
    timestamp: '0x5d11f951',
    timestampFoS: '0x0',
    totalBlockScore: '0x4a9a',
    transactions: [ 
        { 
            blockHash: '0x6ccef34eb59fab927705d344f080f449b576c0626e4aa3e20f569feb8df6e283',
            blockNumber: '0x4a99',
            contractAddress: null,
            from: '0x71959675eeb7c7ec1e0c74f206a9c488d7f178d4',
            gas: '0x493e0',
            gasPrice: '0x5d21dba00',
            gasUsed: '0x5208',
            logs: [],
            logsBloom: '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
            nonce: '0x2',
            senderTxHash: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
            signatures: [ 
                { 
                    V: '0x4e43',
                    R: '0xa857ef0676d7e65697cadeaf1654b2facd71d0b9f942d695f3972a1f7c34c25c',
                    S: '0x43fba9e5c2c16511f951e27957f1279ea3c1f913b27f9fbb2a8dcb5884e37e3d' 
                } 
            ],
            status: '0x1',
            to: '0xef5cd886c7f8d85fbe8023291761341acbb4da01',
            transactionHash: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
            transactionIndex: '0x0',
            type: 'TxTypeValueTransfer',
            typeInt: 8,
            value: '0xde0b6b3a7640000' 
        } 
    ],
    transactionsRoot: '0xac418c96f7386a3343d149eeb29e48e28905525dda2e5afe55b0661f9ab01aca',
    voteData: '0x' 
}

getCommittee

caver.klay.getCommittee([defaultBlock] [, callback])

Returns a list of all validators in the committee at the specified block. If the parameter is not set, returns a list of all validators in the committee at the latest block.

Parameters

Name	Type	Description
defaultBlock	Number | String	(optional) If you pass this parameter, it will not use the default block set with caver.klay.defaultBlock.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Array - Addresses of all validators in the committee.

Example

> caver.klay.getCommittee().then(console.log);
[
    "0x207e38864b45a538733741dc1ff92eff9d1a6159",
    "0x6d64bc82b93368a7f963d6c34483ca3893f405f6",
    "0xbc9c19f91878369776812039e4ebcdfa3c646716",
    "0xe3ed6fa287752b992f936b42360770c59731d9eb"
]

getCommitteeSize

caver.klay.getCommitteeSize([defaultBlock] [, callback])

Returns the size of the committee at the specified block. If the parameter is not set, returns the size of the committee at the latest block.

Parameters

Name	Type	Description
defaultBlock	Number | String	(optional) If you pass this parameter, it will not use the default block set with caver.klay.defaultBlock.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Number - The size of the committee.

Example

> caver.klay.getCommitteeSize().then(console.log);
4

getCouncil

NOTE: getValidators is replaced with this method and is not supported anymore.

caver.klay.getCouncil([defaultBlock] [, callback])

Returns a list of all validators of the council at the specified block. If the parameter is not set, returns a list of all validators of the council at the latest block.

Parameters

Name	Type	Description
defaultBlock	Number | String	(optional) If you pass this parameter, it will not use the default block set with caver.klay.defaultBlock.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Array - Addresses of all validators of the council.

Example

> caver.klay.getCouncil().then(console.log);
[
    "0x207e38864b45a538733741dc1ff92eff9d1a6159",
    "0x6d64bc82b93368a7f963d6c34483ca3893f405f6",
    "0xbc9c19f91878369776812039e4ebcdfa3c646716",
    "0xe3ed6fa287752b992f936b42360770c59731d9eb"
]

getCouncilSize

caver.klay.getCouncilSize([defaultBlock] [, callback])

Returns the size of the council at the specified block. If the parameter is not set, returns the size of the council at the latest block.

Parameters

Name	Type	Description
defaultBlock	Number | String	(optional) If you pass this parameter, it will not use the default block set with caver.klay.defaultBlock.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Number - The size of the council.

Example

> caver.klay.getCouncilSize().then(console.log);
4

getStorageAt

caver.klay.getStorageAt(address, position [, defaultBlock] [, callback])

Gets the storage at a specific position of an address.

Parameters

Name	Type	Description
address	String	The address to get the storage from.
position	Number	The index position of the storage.
defaultBlock	Number | String	(optional) If you pass this parameter, it will not use the default block set with caver.klay.defaultBlock.
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns String - The value in storage at the given position.

Example

> caver.klay.getStorageAt("0x407d73d8a49eeb85d32cf465507dd71d507100c1", 0).then(console.log);
"0x033456732123ffff2342342dd12342434324234234fd234fd23fd4f23d4234"

isMining

caver.klay.isMining([callback])

Returns true if client is actively mining new blocks.

Parameters

Name	Type	Description
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Boolean - true if the client is mining, otherwise false.

Example

> caver.klay.isMining().then(console.log);
true

isSyncing

caver.klay.isSyncing([callback])

Checks if the node is currently syncing and returns either a syncing object or false.

Parameters

Name	Type	Description
callback	Function	(optional) Optional callback, returns an error object as the first parameter and the result as the second.

Return Value

Promise returns Object|Boolean - A sync object when the node is currently syncing or false:

Name	Type	Description
startingBlock	Number	The block number where the sync started.
currentBlock	Number	The block number where at which block the node currently synced to already.
highestBlock	Number	The estimated block number to sync to.
knownStates	Number	The estimated states to download.
pulledStates	Number	The already downloaded states.

Example

> caver.klay.isSyncing().then(console.log);
{
    startingBlock: 100,
    currentBlock: 312,
    highestBlock: 512,
    knownStates: 234566,
    pulledStates: 123455
}