Hedera (HBAR & HTS)

Get Public Key

In order to get public key for Hedera Account, you can use getAddress() function.

If you use DcentWebConnector.coinType.HEDERA as a coinType parameter for getAddress() function, you can get public key for the private key of the BIP44 path.

For more detail about getAddress(), please see the below section.

• go to Get Address API description

Sign Transaction

Supported Transaction Types

Transaction	Supported	Group
AccountCreateTransaction	O	Accounts
AccountUpdateTransaction	O	Accounts
TransferTransaction	O	Accounts
AccountDeleteTransaction	X	Accounts
AccountAllowanceApprovalTransaction	X	Accounts
AccountAllowanceAdjustTransaction	X	Accounts
TokenCreateTransaction	O	Token
TokenUpdateTransaction	O	Token
TokenDeleteTransaction	X	Token
TokenAssociateTransaction	O	Token
TokenDissociateTransaction	O	Token
TokenMintTransaction	O	Token
TokenBurnTransaction	O	Token
TokenFreezeTransaction	O	Token
TokenFeeScheduleUpdateTransaction	X	Token
TokenUnfreezeTransaction	O	Token
TokenGrantKycTransaction	X	Token
TokenRevokeKycTransaction	X	Token
TokenPauseTransaction	O	Token
TokenUnpauseTransaction	O	Token
TokenWipeTransaction	O	Token

For your reference, all transaction types for Hedera can be found here.

• https://docs.hedera.com/guides/docs/sdks/transactions

getHederaSignedTransaction()

Supported Coin Type

• Hedera(HTS)

Parameters :

• unsignedTx: unsigned hexadecimal tx Hedera Docs
• path: key path, wallet sign with that private key with a given key path (BIP32 ex) "m/44'/3030'/0'").
• symbol: symbol, It is a symbol that the wallet displays on the screen.
• decimals: hedera or hts token's decimals.

Requirements:

• DCENT Bridge version 1.2.1 or higher is required.
• DCENT Biometric Wallet version 2.19.3. or higher is required.
• This feature is tested with Hedera JavaScript SDK v2.8.0

Usage:

const _buf2hex = (buffer) => { // buffer is an ArrayBuffer
return Array.prototype.map.call(new Uint8Array(buffer), x => ('00' + x.toString(16)).slice(-2)).join('');
}
const client = HederaSDK.Client.forMainnet()
const nodeList = client._network.getNodeAccountIdsForExecute()
const validStart = Timestamp.generate()
const fromAccountId = AccountId.fromString('accountIdString')
const txId = new TransactionId(fromAccountId, validStart)
const tx = new HederaSDK.TransferTransaction()

// when you transfer hbar
tx.addHbarTransfer(fromAccountId, HederaSDK.Hbar.fromTinybars('-' + amountTinybar))
tx.addHbarTransfer('toAccountIdString', HederaSDK.Hbar.fromTinybars(amountTinybar))

// or you can transfer token like this.
tx.addTokenTransfer(contractAddress, fromAccountId, HederaSDK.Hbar.fromTinybars('-' + amountTinybar))
tx.addTokenTransfer(contractAddress, 'toAccountIdString', HederaSDK.Hbar.fromTinybars(amountTinybar))


tx.setNodeAccountIds([nodeList[nodeList.length - 1]])
tx.setTransactionId(txId)
tx.setTransactionMemo('')
tx.setMaxTransactionFee(fee)
tx.freezeWith(client)

const bodyBytes = tx._signedTransactions[0].bodyBytes
const unsignedTx = _buf2hex(bodyBytes)

const transactionJson = {
    unsignedTx: unsignedTx,
    path: `m/44'/3030'/0'`,
    symbol: HBAR,
    decimals: 8,
}

var result
try {
    result = await DcentWebConnector.getHederaSignedTransaction(transactionJson);    
} catch (e) {
    console.log(e)
    result = e
}

Returned response object:

{
    "header": {
        "version": "1.0",
        "response_from": "hedera",
        "status": "success"
    },
    "body": {
        "command": "transaction",
        "parameter": {
            "signed_tx": "0x31aa13b5e04cb6fc6381ea0520bf7f6727ebdb6e96cd7ca8625bb3e3dd36cf0e2cee4ece13aa9f7ddc09ee10c74aa00af954201829d8016317f10f5a921dcc0d",
            "pubkey": "0x9a5c753d02038e512c06867556324b37181c9c1fc19c21c27752c520e8f0d822"
        }
    }
}