- Install the dependencies
- Initialize the SDK’s
- Deploy a new Safe
- Create a transaction
- Propose the transaction to the service
- Get the transaction from the service
- Confirm/reject the transaction
- Execute the transaction
- Interface checks
To integrate the Safe Core SDK into your Dapp or script you will need to install these dependencies:
@safe-global/types-kit
@safe-global/protocol-kit
@safe-global/api-kit
To use our kits, you need to provide an Ethereum provider and a signer. The provider is the connection to the Ethereum network, while the signer is an account that will sign the transactions (a Safe owner). When using an injected provider like MetaMask, the signer is the account selected in the wallet.
In the examples below, you can see provider
and signer
properties, which represent:
provider
: You can provide an EIP-1193 compatible provider or an HTTP/WebSocket RPC URL.signer
: This is an optional parameter. It should be the provider's address you want to use or a private key. If not set, it will try to fetch a connected account from the provider.
As stated in the introduction, the Safe API Kit consumes the Safe Transaction Service API. To start using this library, create a new instance of the SafeApiKit
class, imported from @safe-global/api-kit
and pass the URL to the constructor of the Safe Transaction Service you want to use depending on the network.
import SafeApiKit from '@safe-global/api-kit'
const apiKit = new SafeApiKit({ chainId })
Using the chainId
is enough for chains where Safe runs a Transaction Service. For those chains where Safe doesn't run a service, use the txServiceUrl
parameter to set the custom service endpoint.
const apiKit = new SafeApiKit({
chainId,
txServiceUrl: 'https://txServiceUrl.com'
})
import Safe from '@safe-global/protocol-kit'
const protocolKit = await Safe.init({ provider, signer, safeAddress })
There are two versions of the Safe contracts: Safe.sol that does not trigger events in order to save gas and SafeL2.sol that does, which is more appropriate for L2 networks.
By default Safe.sol
will be only used on Ethereum Mainnet. For the rest of the networks where the Safe contracts are already deployed, the SafeL2.sol
contract will be used unless you add the property isL1SafeSingleton
to force the use of the Safe.sol
contract.
const protocolKit = await Safe.init({ provider, signer, safeAddress, isL1SafeSingleton: true })
If the Safe contracts are not deployed to your current network, the property contractNetworks
will be required to point to the addresses of the Safe contracts previously deployed by you.
import { ContractNetworksConfig, SafeProvider } from '@safe-global/protocol-kit'
const safeProvider = new SafeProvider({ provider, signer })
const chainId = await safeProvider.getChainId()
const contractNetworks: ContractNetworksConfig = {
[chainId]: {
safeSingletonAddress: '<SINGLETON_ADDRESS>',
safeProxyFactoryAddress: '<PROXY_FACTORY_ADDRESS>',
multiSendAddress: '<MULTI_SEND_ADDRESS>',
multiSendCallOnlyAddress: '<MULTI_SEND_CALL_ONLY_ADDRESS>',
fallbackHandlerAddress: '<FALLBACK_HANDLER_ADDRESS>',
signMessageLibAddress: '<SIGN_MESSAGE_LIB_ADDRESS>',
createCallAddress: '<CREATE_CALL_ADDRESS>',
simulateTxAccessorAddress: '<SIMULATE_TX_ACCESSOR_ADDRESS>',
safeWebAuthnSignerFactoryAddress:'<SAFE_WEB_AUTHN_SIGNER_FACTORY_ADDRESS>',
safeSingletonAbi: '<SINGLETON_ABI>', // Optional. Only needed with web3.js
safeProxyFactoryAbi: '<PROXY_FACTORY_ABI>', // Optional. Only needed with web3.js
multiSendAbi: '<MULTI_SEND_ABI>', // Optional. Only needed with web3.js
multiSendCallOnlyAbi: '<MULTI_SEND_CALL_ONLY_ABI>', // Optional. Only needed with web3.js
fallbackHandlerAbi: '<FALLBACK_HANDLER_ABI>', // Optional. Only needed with web3.js
signMessageLibAbi: '<SIGN_MESSAGE_LIB_ABI>', // Optional. Only needed with web3.js
createCallAbi: '<CREATE_CALL_ABI>', // Optional. Only needed with web3.js
simulateTxAccessorAbi: '<SIMULATE_TX_ACCESSOR_ABI>' // Optional. Only needed with web3.js
safeWebAuthnSignerFactoryAbi: '<SAFE_WEB_AUTHN_SIGNER_FACTORY_ABI>' // Optional. Only needed with web3.js
}
}
const protocolKit = await Safe.init({ provider, signer, safeAddress, contractNetworks })
The Protocol Kit library now simplifies the creation of new Safes by providing the createSafeDeploymentTransaction
method. This method returns an Ethereum transaction object ready for execution, which includes the deployment of a Safe.
Here is an example of how to create a new Safe account with 3 owners and 2 required signatures:
import { SafeAccountConfig } from '@safe-global/protocol-kit'
const safeAccountConfig: SafeAccountConfig = {
owners: ['0x...', '0x...', '0x...'],
threshold: 2
// Additional optional parameters can be included here
}
const predictSafe = {
safeAccountConfig,
safeDeploymentConfig: {
saltNonce, // optional parameter
safeVersion // optional parameter
}
}
const protocolKit = await Safe.init({ provider, signer, predictSafe })
const deploymentTransaction = await protocolKit.createSafeDeploymentTransaction()
// Execute this transaction using the Ethereum client of your choice
const txHash = await client.sendTransaction({
to: deploymentTransaction.to,
value: BigInt(deploymentTransaction.value),
data: `0x${deploymentTransaction.data}`
})
Once you obtain the deploymentTransaction
object, you will have an Ethereum transaction object containing the to
, value
, and data
fields. You can execute this transaction using the Ethereum client of your choice. Check the API Reference for more details on additional configuration parameters.
After successfully executing the transaction and confirming that the Safe has been deployed, you will need to reconnect to the new Safe address. Use the connect
method to reinitialize the protocol-kit instance with the deployed Safe address:
// Execute this transaction using the Ethereum client of your choice
const txHash = await client.sendTransaction({
to: deploymentTransaction.to,
value: BigInt(deploymentTransaction.value),
data: `0x${deploymentTransaction.data}`
})
console.log('Transaction hash:', txHash)
const txReceipt = await waitForTransactionReceipt(client, { hash: txHash })
// Extract the Safe address from the deployment transaction receipt
const safeAddress = getSafeAddressFromDeploymentTx(txReceipt, safeVersion)
console.log('safeAddress:', safeAddress)
// Reinitialize the instance of protocol-kit using the obtained Safe address
protocolKit.connect({ safeAddress })
console.log('is Safe deployed:', await protocolKit.isSafeDeployed())
console.log('Safe Address:', await protocolKit.getAddress())
console.log('Safe Owners:', await protocolKit.getOwners())
console.log('Safe Threshold:', await protocolKit.getThreshold())
The Protocol Kit supports the execution of single Safe transactions but also MultiSend transactions. We can create a transaction object by calling the method createTransaction
in our Safe
instance.
This method takes an array of MetaTransactionData
objects that represent the individual transactions we want to include in our MultiSend transaction. If we want to specify some of the optional properties in our MultiSend transaction, we can pass a second argument to the method createTransaction
with the SafeTransactionOptionalProps
object.
When the array contains only one transaction, it is not wrapped in the MultiSend.
import { SafeTransactionOptionalProps } from '@safe-global/protocol-kit'
import { MetaTransactionData } from '@safe-global/types-kit'
const transactions: MetaTransactionData[] = [
{
to,
data,
value,
operation
},
{
to,
data,
value,
operation
}
// ...
]
const options: SafeTransactionOptionalProps = {
safeTxGas, // Optional
baseGas, // Optional
gasPrice, // Optional
gasToken, // Optional
refundReceiver, // Optional
nonce // Optional
}
const safeTransaction = await protocolKit.createTransaction({ transactions, options })
We can specify the nonce
of our Safe transaction as long as it is not lower than the current Safe nonce. If multiple transactions are created but not executed they will share the same nonce
if no nonce
is specified, validating the first executed transaction and invalidating all the rest. We can prevent this by calling the method getNextNonce
from the Safe API Kit instance. This method takes all queued/pending transactions into account when calculating the next nonce, creating a unique one for all different transactions.
const nonce = await apiKit.getNextNonce(safeAddress)
Once we have the Safe transaction object we can share it with the other owners of the Safe so they can sign it. To send the transaction to the Safe Transaction Service we need to call the method proposeTransaction
from the Safe API Kit instance and pass an object with the properties:
safeAddress
: The Safe address.safeTransactionData
: Thedata
object inside the Safe transaction object returned from the methodcreateTransaction
.safeTxHash
: The Safe transaction hash, calculated by calling the methodgetTransactionHash
from the Protocol Kit.senderAddress
: The Safe owner or delegate proposing the transaction.senderSignature
: The signature generated by signing thesafeTxHash
with thesenderAddress
.origin
: Optional string that allows to provide more information about the app proposing the transaction.
const safeTxHash = await protocolKit.getTransactionHash(safeTransaction)
const senderSignature = await protocolKit.signHash(safeTxHash)
await apiKit.proposeTransaction({
safeAddress,
safeTransactionData: safeTransaction.data,
safeTxHash,
senderAddress,
senderSignature: senderSignature.data,
origin
})
The transaction is then available on the Safe Transaction Service and the owners can retrieve it by finding it in the pending transaction list, or by getting its Safe transaction hash.
Get a list of pending transactions:
const pendingTxs = await apiKit.getPendingTransactions(safeAddress)
Get a specific transaction given its Safe transaction hash:
const tx = await apiKit.getTransaction(safeTxHash)
The retrieved transaction will have this type:
type SafeMultisigTransactionResponse = {
safe: string
to: string
value: string
data?: string
operation: number
gasToken: string
safeTxGas: number
baseGas: number
gasPrice: string
refundReceiver?: string
nonce: number
executionDate: string
submissionDate: string
modified: string
blockNumber?: number
transactionHash: string
safeTxHash: string
executor?: string
isExecuted: boolean
isSuccessful?: boolean
ethGasPrice?: string
gasUsed?: number
fee?: string
origin: string
dataDecoded?: string
confirmationsRequired: number
confirmations?: [
{
owner: string
submissionDate: string
transactionHash?: string
confirmationType?: string
signature: string
signatureType?: SignatureType
},
// ...
]
signatures?: string
}
The owners of the Safe can now sign the transaction obtained from the Safe Transaction Service by calling the method signHash
from the Protocol Kit to generate the signature and by calling the method confirmTransaction
from the Safe API Kit to add the signature to the service.
// transaction: SafeMultisigTransactionResponse
const hash = transaction.safeTxHash
let signature = await protocolKit.signHash(hash)
await apiKit.confirmTransaction(hash, signature.data)
Once there are enough confirmations in the service the transaction is ready to be executed. The account that will execute the transaction needs to retrieve it from the service with all the required signatures and call the method executeTransaction
from the Protocol Kit.
The method executeTransaction
accepts an instance of the class SafeTransaction
so the transaction needs to be transformed from the type SafeMultisigTransactionResponse
.
const safeTransaction = await apiKit.getTransaction(...)
const executeTxResponse = await protocolKit.executeTransaction(safeTransaction)
const receipt = executeTxResponse.transactionResponse && (await executeTxResponse.transactionResponse.wait())
Optionally, the isValidTransaction
method, that returns a boolean value, could be called right before the executeTransaction
method to check if the transaction will be executed successfully or not.
const isValidTx = await protocolKit.isValidTransaction(safeTransaction)
During the process of collecting the signatures/executing transactions, some useful checks can be made in the interface to display or hide a button to confirm or execute the transaction depending on the current number of confirmations, the address of accounts that confirmed the transaction and the Safe threshold:
Check if a Safe transaction is already signed by an owner:
const isTransactionSignedByAddress = (
signerAddress: string,
transaction: SafeMultisigTransactionResponse
) => {
const confirmation = transaction.confirmations.find(
(confirmation) => confirmation.owner === signerAddress
)
return !!confirmation
}
Check if a Safe transaction is ready to be executed:
const isTransactionExecutable = (
safeThreshold: number,
transaction: SafeMultisigTransactionResponse
) => {
return transaction.confirmations.length >= safeThreshold
}