JSON-RPC API

This page introduces how to call JSON-RPC API that Klaytn Endpoint Node offered.

Before Getting Started

• The x-chain-id value for calling the API is 8217 (Cypress) or 1001 (Baobab).

• Essential parameters for calling APIs are described in individual examples.

Values that a user needs to enter for calling APIs will be represented with one pair of braces ({}). A user must enter the following values.

Item	Description	Note
chain-id	8217 or 1001	Cypress(Klaytn mainnet) or Baobab(Klaytn testnet
access-key-id	Auth ID	accessKeyId obtained from KAS Console - Security - Credential
secret-access-key	Auth Password	secretAccessKey obtained from KAS Console - Security - Credential
krn	(optional) ID of Account Pool	Unnecessary when using Default Account Pool

A KAS API Authentication Key (API Auth Key) provides access to all KAS services and all the rights to a Klaytn account which was created by calling Wallet API via this API Auth Key. The rights here include accessing and transferring all the assets (KLAY, etc.) of or sending a transaction from a Klaytn account. If you shared your API Auth Key with any unauthorized personnel, your Klaytn account could be compromised and might cause unwanted transaction execution.

DO NOT share your API Auth Key (Secret AccessKey or Authorization) with any unauthorized personnel. DO PUT efforts necessary to keep your API Auth Key safe for the security of your KAS/Klaytn account.

For details about KAS SDK (caver-js/caver-java extensions) installation and execution, please visit KAS SDK. To check Klaytn account information through Klaytn Node, create an Account Pool and select an account to use. For more details on creating an Account Pool, account, and selecting an account, refer to Getting Started.

Get Klaytn account Information on Klaytn Node

Check the Block Number of the Most Recent Block

The block number of the latest block on Klaytn is required for checking the account balance, key type, and other recent information on the account using Node API. To this end, a user must send the JSON-RPC request { "method": "klay_blockNumber", "id": 1 } for the latest block number.

For more details about Node API, please visit here.

API Request

curl

curl --location --request POST "https://node-api.klaytnapi.com/v2/klaytn" \
    -u {accessKeyId}:{secretAccessKey} \
    --header "x-chain-id: {chain-id}" \
    --header "Content-Type: application/json" \
    --data-raw "{"jsonrpc":"2.0","method":"klay_blockNumber","params":[],"id":1}"

javascript

const accessKeyId = "{accessKeyId}"
const secretAccessKey = "{secretAccessKey}"
const chainId = 1001

const caver = new CaverExtKAS()
caver.initKASAPI(chainId, accessKeyId, secretAccessKey)
const blockNumber = await caver.rpc.klay.getBlockNumber()

java

String accessKey = "your accessKey";
String secretAccessKey = "your secret accessKey";

CaverExtKAS caver = new CaverExtKAS();
caver.initKASAPI(1001, accessKey, secretAccessKey);

Quantity response = caver.rpc.klay.getBlockNumber().send();
System.out.println(response.getValue());

• “id” is a random value.

• “params” and “jsonrpc” can be omitted.

For more details about API Request, please visit here.

Node API calls different Klaytn endpoint nodes each time, and the result value may be unexpected if “pending” is entered as the block number.

API Response

The following response will be received if the API is successfully executed.

curl

{
    "jsonrpc": "2.0",
    "id": 1,
    "result": "0x5d39"
}

javascript

0x5d39

java

0x5d39

• “result” is a block number value represented in hexadecimal.

For details about Klaytn JSON-RPC API, please visit here. For details about this API, please visit here. For inquires about this document or KAS, please visit KAS Developer forum.

Get Klaytn account Information by EOA

API Request

Enter the block number and Klaytn EOA, and then, execute the JSON-RPC function, klay_getAccount, to search for account information. klay_getAccount then receives the address (required) and block number/tag (required or optional) parameters. The block number and tag parameters are needed if RPC is directly called through curl or other HTTP methods.

curl

curl --location --request POST "https://node-api.klaytnapi.com/v2/klaytn" \
    -u {accessKeyId}:{secretAccessKey} \
    --header "x-chain-id: 8217" \
    --header "Content-Type: application/json" \
    --data-raw "{"jsonrpc":"2.0","method":"klay_getAccount","params":["0x3111a0577f322e8fb54f78d9982a26ae7ca0f722", "0x5d39"],"id":1}"

javascript

const accessKeyId = "{accessKeyId}"
const secretAccessKey = "{secretAccessKey}"
const chainId = 1001
const caver = new CaverExtKAS()

caver.initKASAPI(chainId, accessKeyId, secretAccessKey)
const account = await caver.rpc.klay.getAccount()

java

String accessKey = "your accessKey";
String secretAccessKey = "your secret accessKey";

CaverExtKAS caver = new CaverExtKAS();
caver.initKASAPI(1001, accessKey, secretAccessKey);

Account res = caver.rpc.klay.getAccount("0x3111a0577f322e8fb54f78d9982a26ae7ca0f722").send();

• “id” is a random value.

• “jsonrpc” can be omitted.

• This is an example of Klaytn account address value: 0x3111a0577f322e8fb54f78d9982a26ae7ca0f722.

• According to the implementation of SDK (caver-js, caver-java), the block number/tag can be omitted. Here, the “latest” tag is used.

For more details about API Request, please visit here.

Node API calls different Klaytn endpoint nodes each time, and the result value may be unexpected if “pending” is entered as the block number.

API Response

Once the API is successfully executed, the user will receive a response regarding the information of the Klaytn account that entered the EOA.

curl

{
    "jsonrpc": "2.0",
    "id": 1,
    "result": {
        "accType": 1,
        "account": {
            "nonce": 4,
            "balance": "0x8d286271f52600",
            "humanReadable": false,
            "key": {
                "keyType": 1,
                "key": {}
            }
        }
    }
}

javascript

{
    accType: 1,
    account: {
        nonce: 4,
        balance: "0x8d286271f52600",
        humanReadable: false,
        key: { keyType: 1, key: {} }
    }
}

java

/* skipped */

For details about Klaytn JSON-RPC API, please visit here. For details about this API, please visit here. For inquires about this document or KAS, please visit KAS Developer forum.

List of Node API KAS Currently Supports

Other JSON-RPC APIs of Klaytn can be called through KAS using the same process. However, KAS only supports a few Node APIs currently. Here is a list of Node APIs supported by KAS.

Category	Module	Method	Support
Platform	Account	klay_isContractAccount	O
Platform	Account	klay_getTransactionCount	O
Platform	Account	klay_getCode	O
Platform	Account	klay_getBalance	O
Platform	Account	klay_getAccountKey	O
Platform	Account	klay_getAccount	O
Platform	Account	klay_accountCreated	O
Platform	Account	klay_encodeAccountKey	O
Platform	Account	klay_decodeAccountKey	O
Platform	Block	klay_syncing	O
Platform	Block	klay_getStorageAt	O
Platform	Block	klay_getCouncilSize	O
Platform	Block	klay_getCouncil	O
Platform	Block	klay_getCommitteeSize	O
Platform	Block	klay_getCommittee	O
Platform	Block	klay_getBlockWithConsensusInfoByNumber	O
Platform	Block	klay_getBlockWithConsensusInfoByHash	O
Platform	Block	klay_getBlockTransactionCountByNumber	O
Platform	Block	klay_getBlockTransactionCountByHash	O
Platform	Block	klay_getBlockReceipts	O
Platform	Block	klay_getBlockByNumber	O
Platform	Block	klay_getBlockByHash	O
Platform	Block	klay_blockNumber	O
Platform	Configuration	klay_protocolVersion	O
Platform	Configuration	klay_gasPriceAt	O
Platform	Configuration	klay_gasPrice	O
Platform	Configuration	klay_clientVersion	O
Platform	Configuration	klay_chainID	O
Platform	Filter	klay_getLogs	O
Platform	Miscellaneous	klay_sha3	O
Platform	Transaction	klay_sendRawTransaction	O
Platform	Transaction	klay_getTransactionReceipt	O
Platform	Transaction	klay_getTransactionByHash	O
Platform	Transaction	klay_getTransactionByBlockNumberAndIndex	O
Platform	Transaction	klay_getTransactionByBlockHashAndIndex	O
Platform	Transaction	klay_estimateGas	O
Platform	Transaction	klay_estimateComputationCost	O
Platform	Transaction	klay_call	O
Network	net	net_peerCountByType	O
Network	net	net_peerCount	O
Network	net	net_networkID	O
Network	net	net_listening	O
Platform	Account	klay_sign	X
Platform	Account	klay_accounts	X
Platform	Block	klay_mining	X
Platform	Filter	klay_uninstallFilter	X
Platform	Filter	klay_newPendingTransactionFilter	X
Platform	Filter	klay_newFilter	X
Platform	Filter	klay_newBlockFilter	X
Platform	Filter	klay_getFilterLogs	X
Platform	Filter	klay_getFilterChanges	X
Debug	Blockchain Inspection	debug_setHead	X
Debug	Blockchain Inspection	debug_printBlock	X
Debug	Blockchain Inspection	debug_preimage	X
Debug	Blockchain Inspection	debug_getModifiedAccountsByNumber	X
Debug	Blockchain Inspection	debug_getModifiedAccountsByHash	X
Debug	Blockchain Inspection	debug_getBlockRlp	X
Debug	Blockchain Inspection	debug_dumpBlock	X
Platform	Configuration	klay_writeThroughCaching	X
Platform	Configuration	klay_rewardbase	X
Platform	Configuration	klay_isSenderTxHashIndexingEnabled	X
Platform	Configuration	klay_isParallelDBWrite	X
Governance	Governance	governance_vote	X
Governance	Governance	governance_totalVotingPower	X
Governance	Governance	governance_showTally	X
Governance	Governance	governance_nodeAddress	X
Governance	Governance	governance_myVotingPower	X
Governance	Governance	governance_myVotes	X
Governance	Governance	governance_itemsAt	X
Governance	Governance	governance_chainConfig	X
Debug	Logging	debug_vmodule	X
Debug	Logging	debug_verbosity	X
Debug	Logging	debug_setVMLogTarget	X
Debug	Logging	debug_backtraceAt	X
service chain	Main-bridge	convertServiceChainBlockHashToMainChainTxHash	X
Debug	Profiling	debug_writeMemProfile	X
Debug	Profiling	debug_writeBlockProfile	X
Debug	Profiling	debug_stopPProf	X
Debug	Profiling	debug_stopCPUProfile	X
Debug	Profiling	debug_startPProf	X
Debug	Profiling	debug_startCPUProfile	X
Debug	Profiling	debug_setBlockProfileRate	X
Debug	Profiling	debug_isPProfRunning	X
Debug	Profiling	debug_cpuProfile	X
Debug	Profiling	debug_blockProfile	X
Debug	Runtime Debugging	debug_stacks	X
Debug	Runtime Debugging	debug_setGCPercent	X
Debug	Runtime Debugging	debug_metrics	X
Debug	Runtime Debugging	debug_memStats	X
Debug	Runtime Debugging	debug_gcStats	X
Debug	Runtime Debugging	debug_freeOSMemory	X
Debug	Runtime Tracing	debug_stopGoTrace	X
Debug	Runtime Tracing	debug_startGoTrace	X
Debug	Runtime Tracing	debug_goTrace	X
service chain	Sub-bridge	sendChainTxslimit	X
service chain	Sub-bridge	latestAnchoredBlockNumber	X
service chain	Sub-bridge	anchoring	X
Platform	Transaction	klay_signTransaction	X
Platform	Transaction	klay_sendTransaction	X
Platform	Transaction	klay_getTransactionReceiptBySenderTxHash	X
Platform	Transaction	klay_getTransactionBySenderTxHash	X
Debug	VM Standard Tracing	debug_standardTraceBlockToFile	X
Debug	VM Standard Tracing	debug_standardTraceBadBlockToFile	X
Debug	VM Tracing	debug_traceTransaction	X
Debug	VM Tracing	debug_traceBlockFromFile	X
Debug	VM Tracing	debug_traceBlockByNumber	X
Debug	VM Tracing	debug_traceBlockByHash	X
Debug	VM Tracing	debug_traceBlock	X
Debug	VM Tracing	debug_traceBadBlock	X
Management	admin	admin_stopWS	X
Management	admin	admin_stopRPC	X
Management	admin	admin_startWS	X
Management	admin	admin_startRPC	X
Management	admin	admin_removePeer	X
Management	admin	admin_peers	X
Management	admin	admin_nodeInfo	X
Management	admin	admin_importChain	X
Management	admin	admin_exportChain	X
Management	admin	admin_datadir	X
Management	admin	admin_addPeer	X
service chain	service chain	removePeer	X
service chain	service chain	nodeInfo	X
service chain	service chain	addPeer	X
Management	personal	personal_unlockAccount	X
Management	personal	personal_sign	X
Management	personal	personal_sendValueTransfer	X
Management	personal	personal_sendTransaction	X
Management	personal	personal_sendAccountUpdate	X
Management	personal	personal_replaceRawKey	X
Management	personal	personal_newAccount	X
Management	personal	personal_lockAccount	X
Management	personal	personal_listAccounts	X
Management	personal	personal_importRawKey	X
Management	personal	personal_ecRecover	X
Management	txpool	txpool_status	X
Management	txpool	txpool_inspect	X
Management	txpool	txpool_content	X

For inquires about this document or KAS, please visit KAS Developer forum.