EVM: Broadcast Transaction

EVM chains like Ethereum, Polygon, BSC, Arbitrum, etc support the use of templates to broadcast transactions. Select the following based on the template kind:

• Evm: Use this template if you don't want to worry about gas parameters.

• Eip1559: Use this template to interact with chains that support the new EIP-1559 gas standard (most chains do now).

• Transaction: Use this template to just pass in the fully serialized EVM transaction (formatted and encoded using eg Ethersjs library)

EVM Template

Request fields	Required - Type	Description
kind*	Required - String	Evm
to*	Required - String	Blockchain address of target contract or payee.
value	(Optional. Required only if making a payment) - String (representing a integer eg "1000000")	Amount of the native currency to transfer denominated in WEI.
data	(Optional) String	Encoded hex string indicating which function in the smart contract to call with which parameters. Can also be an entire encoded contract in the case of contract deployment.
nonce	(Optional) Integer	The transaction number to guarantee idempotency. If omitted, it will be provided automatically. Note the same nonce can be submitted multiple times with a higher maxFeePerGas to "overwrite" existing transactions in the mempool.
externalId	(Optional) String	A unique ID from your system. It can be leveraged to be used as an idempotency key (read more here)

Sample request body

{
    "kind": "Evm",
    "to": "0x00fb58432ef9d418bf6688bcf0a226d2fcaa18e2",
    "data": "0x40d097c3000000000000000000000000d2f77f85a50cdd650ca562f3a180284e1d5b4934",
}

200 response example

{
  "id": "tx-hpq5n-4p9s9-xxxxxxxxxxxxxxxx",
  "walletId": "wa-1f04s-lqc9q-xxxxxxxxxxxxxxxx",
  "network": "EthereumSepolia",
  "requester": {
    "userId": "us-3v1ag-v6b36-xxxxxxxxxxxxxxxx",
    "tokenId": "to-7mkkj-c831n-xxxxxxxxxxxxxxxx",
    "appId": "ap-24vva-92s32-xxxxxxxxxxxxxxxx"
  },
  "requestBody": {
    "kind": "Evm",
    "to": "0x00fb58432ef9d418bf6688bcf0a226d2fcaa18e2",
    "data": "0x40d097c3000000000000000000000000d2f77f85a50cdd650ca562f3a180284e1d5b4934"
  },
  "status": "Broadcasted",
  "txHash": "0x86b092a7fde26cca7fa49350d6d9244fb1f772d30c15aed48decea11fa68531f",
  "dateRequested": "2023-05-08T19:27:04.680Z",
  "dateBroadcasted": "2024-01-10T21:19:58.225Z"
}

EIP-1559 Template

Use this template to adjust the maxFeePerGas and maxPriorityFeePerGas of an EIP-1559 type-2 transaction. Keep in mind that not all EVM compatible chains support this standard.

Property	Required - Type	Description
kind*	String	Eip1559
to*	String	Blockchain address of target contract or payee.
value	(Optional - Required if making a payment) - String (representing an integer eg "1000000")	Amount of the native currency to transfer denominated in WEI.
data	(Optional) String	Encoded hex string indicating which function in the smart contract to call with which parameters. Can also be an entire encoded contract in the case of contract deployment.
nonce	(Optional) Integer	The transaction number to guarantee idempotency. If omitted, it will be provided automatically. Note the same nonce can be submitted multiple times with a higher maxFeePerGas to "overwrite" existing transactions in the mempool.
gasLimit	(Optional) String (representing an Integer)	The maximum amount of gas that can be spent for executing the transaction. If omitted, it will be calculated automatically.
maxPriorityFeePerGas	(Optional) String (representing an Integer)	The maximum amount of gas to be included as a tip to the validator. If omitted, it will be calculated automatically.
maxFeePerGas	(Optional) String (representing an Integer)	The maximum amount for gas willing to be paid for the transaction. If omitted, it will be calculated automatically.
externalId	(Optional) String	A unique ID from your system. It can be leveraged to be used as an idempotency key (read more here)

Sample request body

{
    "kind": "Eip1559",
    "to": "0x00fb58432ef9d418bf6688bcf0a226d2fcaa18e2",
    "data": "0x40d097c3000000000000000000000000d2f77f85a50cdd650ca562f3a180284e1d5b4934",
    "maxFeePerGas": "1626000000000",
    "maxPriorityFeePerGas": "1332000000000"
}

200 response example

{
  "id": "tx-hpq5n-4p9s9-xxxxxxxxxxxxxxxx",
  "walletId": "wa-1f04s-lqc9q-xxxxxxxxxxxxxxxx",
  "network": "EthereumSepolia",
  "requester": {
    "userId": "us-3v1ag-v6b36-xxxxxxxxxxxxxxxx",
    "tokenId": "to-7mkkj-c831n-xxxxxxxxxxxxxxxx",
    "appId": "ap-24vva-92s32-xxxxxxxxxxxxxxxx"
  },
  "requestBody": {
    "kind": "Eip1559",
    "to": "0x00fb58432ef9d418bf6688bcf0a226d2fcaa18e2",
    "data": "0x40d097c3000000000000000000000000d2f77f85a50cdd650ca562f3a180284e1d5b4934",
    "maxFeePerGas": "1626000000000",
    "maxPriorityFeePerGas": "1332000000000"
  },
  "status": "Broadcasted",
  "txHash": "0x86b092a7fde26cca7fa49350d6d9244fb1f772d30c15aed48decea11fa68531f",
  "dateRequested": "2023-05-08T19:27:04.680Z",
  "dateBroadcasted": "2024-01-10T21:19:58.225Z"
}

Raw Transaction

You can also format the transaction using Ethers JS and the Dfns SDK:

Property	Type	Description
kind*	String	Transaction
transaction*	Hex String	The unsigned hex encoded transaction as shown below
externalId	(Optional) String	A unique ID from your system. It can be leveraged to be used as an idempotency key (read more here)

Sample request body

{
  "kind": "Transaction",
  "transaction": "0x02e783aa36a71503850d40e49def82520894e5a2ebc128e262ab1e3bd02bffbe16911adfbffb0180c0"
}

200 Response Example

{
  "id": "tx-3p6n9-tdrn2-xxxxxxxxxxxxxxxx",
  "walletId": "wa-19lns-o74qn-xxxxxxxxxxxxxxxx",
  "network": "EthereumSepolia",
  "requester": {
    "userId": "us-3v1ag-v6b36-xxxxxxxxxxxxxxxx",
    "tokenId": "to-7mkkj-c831n-xxxxxxxxxxxxxxxx",
    "appId": "ap-24vva-92s32-xxxxxxxxxxxxxxxx"
  },
  "requestBody": {
    "kind": "Transaction",
    "transaction": "0x02e783aa36a71503850d40e49def82520894e5a2ebc128e262ab1e3bd02bffbe16911adfbffb0180c0"
  },
  "status": "Broadcasted",
  "txHash": "0x86b092a7fde26cca7fa49350d6d9244fb1f772d30c15aed48decea11fa68531f",
  "dateRequested": "2024-01-10T19:02:11.615Z",
  "dateBroadcasted": "2024-01-10T19:02:12.873Z"
}

Typescript Example with Ethers

First install the Ethers JS. You can find the full documentation here: https://docs.ethers.org/v6/

Here a code sample to broadcast a transaction via the Dfns TypeScript SDK:

import { parseUnits, Transaction } from 'ethers'

const walletId = 'wa-6lbfv-9esgj-xxxxxxxxxxxxxxxx'

const transaction = Transaction.from({
  to: '0xa238b6008Bc2FBd9E386A5d4784511980cE504Cd',
  value: '1',
  gasLimit: '21000',
  maxPriorityFeePerGas: parseUnits('5', 'gwei'),
  maxFeePerGas: parseUnits('20', 'gwei'),
  nonce: 3,
  type: 2,
  chainId: 11155111,
})

const res = await dfnsClient.wallets.broadcastTransaction({
  walletId,
  body: { kind: 'Transaction', transaction: transaction.unsignedSerialized },
})