Transaction Module

This module provides functionalities to send transactions on BandChain which requires <Msg> to be included.

Exceptions

Type	Description
ValueError	Invalid value
NotIntegerError	The value is not an integer
EmptyMsgError	No messages given to the transaction
UndefinedError	The value should not be undefined

withMessages(msgs)

Add one or multiple messages as a list of Google Protobuf's Any to Transaction. There are predefined message classes that can be used to convert to Any instance using toAny() method, but for the other type of message can be converted to Any instance using Any.pack() as shown in the code below.

import { MsgCreateDataSource } from '@bandprotocol/bandchain.js/proto/oracle/v1/tx_pb'
import { Any } from 'google-protobuf/google/protobuf/any_pb'
import { Transaction } from '@bandprotocol/bandchain.js'

const msg = new MsgCreateDataSource()
msg.setName('dsName')
msg.setDescription('dsDescription')
// msg.set...() for every fields

const anyMsg = new Any()
const typeUrl = 'oracle.v1.MsgCreateDataSource'
anyMsg.pack(msg.serializeBinary(), typeUrl, '/')

const tx = new Transaction()
tx.withMessages(anyMsg)

Parameter

• *msgs Any Messages converted to Any to be included in the transaction

Return

• Transaction - This transaction instance for function chaining

withSender(client, sender)

Set account number and sequence number to Transaction from querying the account via Client's getAccount.

Parameter

• client Client - An instance of Client module
• sender string - A bech32-encoded with account prefix

Return

• Promise<Transaction> - This transaction instance for function chaining

Exceptions

Type	Description
EmptyMsgError	Message is empty, please use withMessages at least 1 message
NotFoundError	Account doesn't exist.

withAccountNum(accountNum)

Set account number to Transaction.

Parameter

• accountNum number - An integer of account number, which can be gathered from querying the account via Client's getAccount.

Return

• Transaction - This transaction instance for function chaining

Exceptions

Type	Description
NotIntegerError	accountNum is not an integer

withSequence(sequence)

Set sequence number to Transaction.

Parameter

• sequence Number - An integer of account's sequence number, which can be gathered from querying the account via Client's getAccount.

Return

• Transaction - This transaction instance for function chaining

Exceptions

Type	Description
NotIntegerError	sequence is not an integer

withChainId(chainId)

Set chain id to Transaction.

Parameter

• chainId string - a string of chain ID, which can be gathered from Client's getChainId.

Return

• Transaction - This transaction instance for function chaining

withFee(fee)

Set fee to Transaction.

Parameter

• fee - Set fee limit spent for gas price of the transaction.

Return

• Transaction - This transaction instance for function chaining

Exceptions

Type	Description
NotIntegerError	fee is not an integer

withMemo(memo)

Set memo to Transaction.

Parameter

• memo string - an arbitrary string to remember the transaction. Memo length is limited to 256.

Exceptions

Type	Description
ValueTooLargeError	memo is too large.

Return

• Transaction - This transaction instance for function chaining

getSignDoc()

Get serialized data of transaction's content to be signed from Transaction by using SIGNMODE_DIRECT. See more about signing mode.

Return

• Uint8Array - A byte array of serialized transaction content data, ready for signing.

Exceptions

Type	Description
EmptyMsgError	message is empty
UndefinedError	accountNum should be defined
UndefinedError	sequence should be defined
UndefinedError	chainID should be defined

getSignMessage()

Get serialized data of transaction's content to be signed from Transaction by using SIGN_MODE_LEGACY_AMINO_JSON. See more about signing mode. When using the Ledger to sign message, you need to use this method.

Return

• Uint8Array - A byte array of serialized transaction content data, ready for signing.

getTxData(signature, publicKey, signMode)

Get transaction data from Transaction.

Parameter

• signature Uint8Array - signature for the transaction
• pubkey PublicKey - an instance of public key to be included in the transaction
• signMode SignMode - a signing mode with its own security guarantees representation. (Default: SIGN_MODE_DIRECT)

Return

• Uint8Array - Serialized data of signed transaction, ready to be broadcasted to BandChain.

Exceptions

Type	Description
UndefinedError	accountNum should be defined
UndefinedError	sequence should be defined

Example

import { Client, Wallet, Transaction, Message, Coin, Fee } from '@bandprotocol/bandchain.js'

const { PrivateKey } = Wallet
const client = new Client('https://laozi-testnet6.bandchain.org/grpc-web')

// Step 2.1 import private key based on given mnemonic string
const privkey = PrivateKey.fromMnemonic(
  'subject economy equal whisper turn boil guard giraffe stick retreat wealth card only buddy joy leave genuine resemble submit ghost top polar adjust avoid'
)
// Step 2.2 prepare public key and its address
const pubkey = privkey.toPubkey()
const sender = pubkey.toAddress().toAccBech32()

const sendCoin = async () => {
  // Step 3.1 constructs MsgSend message
  const { MsgSend } = Message

  // Here we use different message type, which is MsgSend
  const receiver = 'band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f'
  const sendAmount = new Coin()
  sendAmount.setDenom('uband')
  sendAmount.setAmount('10')
  const msg = new MsgSend(sender, receiver, [sendAmount])
  // Step 3.2 constructs a transaction
  const account = await client.getAccount(sender)
  const chainId = 'band-laozi-testnet6'

  let feeCoin = new Coin()
  feeCoin.setDenom('uband')
  feeCoin.setAmount('1000')

  const fee = new Fee()
  fee.setAmountList([feeCoin])
  fee.setGasLimit(1000000)
  const tx = new Transaction()
    .withMessages(msg)
    .withAccountNum(account.accountNumber)
    .withSequence(account.sequence)
    .withChainId(chainId)
    .withFee(fee)

  // Step 4 sign the transaction
  const txSignData = tx.getSignDoc(pubkey)
  const signature = privkey.sign(txSignData)
  const signedTx = tx.getTxData(signature, pubkey)

  // Step 5 send the transaction
  const response = await client.sendTxBlockMode(signedTx)
  console.log(JSON.stringify(response))
}

;(async () => {
  await sendCoin()
})()

Result

{
  "height": 144075,
  "txhash": "FB0C1B122116EC1C94EE3BC05FC86B41EC580AC5A6CC7F5A3954F61E0505C648",
  "codespace": "",
  "code": 0,
  "data": "0A1E0A1C2F636F736D6F732E62616E6B2E763162657461312E4D736753656E64",
  "rawLog": "[{\"events\":[{\"type\":\"coin_received\",\"attributes\":[{\"key\":\"receiver\",\"value\":\"band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f\"},{\"key\":\"amount\",\"value\":\"10uband\"}]},{\"type\":\"coin_spent\",\"attributes\":[{\"key\":\"spender\",\"value\":\"band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph\"},{\"key\":\"amount\",\"value\":\"10uband\"}]},{\"type\":\"message\",\"attributes\":[{\"key\":\"action\",\"value\":\"/cosmos.bank.v1beta1.MsgSend\"},{\"key\":\"sender\",\"value\":\"band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph\"},{\"key\":\"module\",\"value\":\"bank\"}]},{\"type\":\"transfer\",\"attributes\":[{\"key\":\"recipient\",\"value\":\"band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f\"},{\"key\":\"sender\",\"value\":\"band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph\"},{\"key\":\"amount\",\"value\":\"10uband\"}]}]}]",
  "logsList": [
    {
      "msgIndex": 0,
      "log": "",
      "eventsList": [
        {
          "type": "coin_received",
          "attributesList": [
            {
              "key": "receiver",
              "value": "band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f"
            },
            { "key": "amount", "value": "10uband" }
          ]
        },
        {
          "type": "coin_spent",
          "attributesList": [
            {
              "key": "spender",
              "value": "band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph"
            },
            { "key": "amount", "value": "10uband" }
          ]
        },
        {
          "type": "message",
          "attributesList": [
            { "key": "action", "value": "/cosmos.bank.v1beta1.MsgSend" },
            {
              "key": "sender",
              "value": "band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph"
            },
            { "key": "module", "value": "bank" }
          ]
        },
        {
          "type": "transfer",
          "attributesList": [
            {
              "key": "recipient",
              "value": "band1p46uhvdk8vr829v747v85hst3mur2dzlmlac7f"
            },
            {
              "key": "sender",
              "value": "band18p27yl962l8283ct7srr5l3g7ydazj07dqrwph"
            },
            { "key": "amount", "value": "10uband" }
          ]
        }
      ]
    }
  ],
  "info": "",
  "gasWanted": 200000,
  "gasUsed": 66907,
  "timestamp": ""
}