Value Transfer

TxTypeValueTransfer is used when a user wants to send KAIA.

As kaia provides multiple transaction types to make each transaction type serve a single purpose, TxTypeValueTransfer is limited to send KAIA to an externally owned account (EOA).

Import extend from web3py_ext to extend web3 to kaia web3

Import necessary utils from eth_account, web3py_ext and cytoolz

Create a Web3 instance with the specified kairos testnet URL

Also, you can change the provider URL from kairos to quicknode

Load an account from private key

Create an empty transaction of type TxType.VALUE_TRANSFER. You can use empty_tx util to get a tx with default fields filled.

Merge the additional fields like from, to and value into the empty tx by using the merge util.

You can use the Web3.to_peb util to convert decimal

Use fill_transaction to add more params to transaction object like gas limit...

Sign the value transfer tx by user's private key

Recover the signer's address from the signature in signed tx

You can decode the RLP-encoded tx by the Account.decode_transaction util and if you want to make the output format pretty, use the to_pretty util

Send the tx to the blockchain. It will return the tx hash, which will be used to wait the receipt

The wait_for_transaction_receipt method returns the tx receipt if it is completed in the blockchain

Finally, get the result.

txTypeValueTransferTransaction.py


from web3py_ext import extend
from web3 import Web3
from eth_account import Account
from web3py_ext.transaction.transaction import (
    empty_tx,
    fill_transaction,
    TxType
)
from web3py_ext.utils.klaytn_utils import to_pretty
from cytoolz import merge
w3 = Web3(Web3.HTTPProvider(
  'https://public-en-kairos.node.kaia.io'
  ))
def web3_value_transfer_sign_recover():
    user = Account.from_key('0x0e4ca6d38096ad99324de0dde108587e5d7c600165ae4cd6c2462c597458c2b8')
    value_transfer_tx = empty_tx(TxType.VALUE_TRANSFER)
    value_transfer_tx = merge(value_transfer_tx, {
        'from' : user.address,
        'to' : user.address,
        'value' : Web3.to_peb(10, "klay"),
    })
    value_transfer_tx = fill_transaction(value_transfer_tx, w3)
    # sign the kaia specific transaction type with web3py
    signed_tx = Account.sign_transaction(value_transfer_tx, user.key)
    print("\nraw transaction of signed tx:", signed_tx.rawTransaction.hex())
    recovered_tx = Account.recover_transaction(signed_tx.rawTransaction)
    print("\nrecovered sender address", recovered_tx)
    decoded_tx = Account.decode_transaction(signed_tx.rawTransaction)
    print("\ndecoded transaction:", to_pretty(decoded_tx))
    tx_hash = w3.eth.send_raw_transaction(signed_tx.rawTransaction)
    tx_receipt = w3.eth.wait_for_transaction_receipt(tx_hash)
    print('tx hash: ', tx_hash, 'receipt: ', tx_receipt)
web3_value_transfer_sign_recover()

output


❯ node txTypeValueTransferTransaction.py
raw transaction of signed tx: 0x08f888820365850ba43b740082f61894a2a8854b1802d8cd5de631e690817c253d6a9153888ac7230489e8000094a2a8854b1802d8cd5de631e690817c253d6a9153f847f8458207f6a0fa9c7e720916e53b587bebc1b6dfdf3fa75c4390936353f4f9e9c446688be6a4a00ac3553e050f18a566541ffa15d6dd36566c077059514c90ad2570a36b29df2c
recovered sender address 0xA2a8854b1802D8Cd5De631E690817c253d6a9153
decoded transaction: {
  "type": 8,
  "to": "0xA2a8854b1802D8Cd5De631E690817c253d6a9153",
  "value": 10000000000000000000,
  "nonce": 869,
  "gasPrice": 50000000000,
  "gas": 63000,
  "from": "0xA2a8854b1802D8Cd5De631E690817c253d6a9153",
  "signatures": [
    {
      "v": 2038,
      "r": 113354712982352869976369229827103350581481011848350586238649071308501699782308,
      "s": 4868251983953391094440263137126339926417283017062042162724837386880119594796
    }
  ],
  "chainId": 1001
}
tx hash:  0xd47018a0bc908e18f980bc59ee454e6016317300e4f207341eaa77a8c841bc0f receipt:  AttributeDict({'blockHash': HexBytes('0xe873b7f3bb39ce89131fbbfc727bca00f1998a4b617e89d1db20d55fc479e32d'), 'blockNumber': 147339314, 'contractAddress': None, 'cumulativeGasUsed': 352123, 'effectiveGasPrice': 25000000000, 'from': '0xA2a8854b1802D8Cd5De631E690817c253d6a9153', 'gasUsed': 21000, 'logs': [], 'logsBloom': HexBytes('0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000'), 'status': 1, 'to': '0xA2a8854b1802D8Cd5De631E690817c253d6a9153', 'transactionHash': HexBytes('0xd47018a0bc908e18f980bc59ee454e6016317300e4f207341eaa77a8c841bc0f'), 'transactionIndex': 2, 'type': 0})