ethers.js/docs/v5/api/signer/README.md
2020-07-05 00:02:47 -04:00

12 KiB

Documentation: html

Signers

Signer

signer . connect( provider ) => Signer

Sub-classes must implement this, however they may simply throw an error if changing providers is not supported.

signer . getAddress( ) => Promise< string< Address > >

Returns a Promise that resolves to the account address.

This is a Promise so that a Signer can be designed around an asynchronous source, such as hardware wallets.

Sub-classes must implement this.

Signer . isSigner( object ) => boolean

Returns true if an only if object is a Signer.

Blockchain Methods

signer . getBalance( [ blockTag = "latest" ] ) => Promise< BigNumber >

Returns the balance of this wallet at blockTag.

signer . getChainId( ) => Promise< number >

Returns the chain ID this wallet is connected to.

signer . getGasPrice( ) => Promise< BigNumber >

Returns the current gas price.

signer . getTransactionCount( [ blockTag = "latest" ] ) => Promise< number >

Returns the number of transactions this account has ever sent. This is the value required to be included in transactions as the nonce.

signer . call( transactionRequest ) => Promise< string< DataHexString > >

Returns the result of calling using the transactionRequest, with this account address being used as the from field.

signer . estimateGas( transactionRequest ) => Promise< BigNumber >

Returns the result of estimating the cost to send the transactionRequest, with this account address being used as the from field.

signer . resolveName( ensName ) => Promise< string< Address > >

Returns the address associated with the ensName.

Signing

signer . signMessage( message ) => Promise< string< RawSignature > >

This returns a Promise which resolves to the Raw Signature of message.

Sub-classes must implement this, however they may throw if signing a message is not supported, such as in a Contract-based Wallet or Meta-Transaction-based Wallet.

Note

If message is a string, it is treated as a string and converted to its representation in UTF8 bytes.

If and only if a message is a Bytes will it be treated as binary data.

For example, the string "0x1234" is 6 characters long (and in this case 6 bytes long). This is not equivalent to the array [ 0x12, 0x34 ], which is 2 bytes long.

A common case is to sign a hash. In this case, if the hash is a string, it must be converted to an array first, using the arrayify utility function.

signer . signTransaction( transactionRequest ) => Promise< string< DataHexString > >

Returns a Promise which resolves to the signed transaction of the transactionRequest. This method does not populate any missing fields.

Sub-classes must implement this, however they may throw if signing a transaction is not supported, which is common for security reasons in many clients.

signer . sendTransaction( transactionRequest ) => Promise< TransactionResponse >

This method populates the transactionRequest with missing fields, using populateTransaction and returns a Promise which resolves to the transaction.

Sub-classes must implement this, however they may throw if sending a transaction is not supported, such as the VoidSigner or if the Wallet is offline and not connected to a Provider.

Sub-Classes

signer . checkTransaction( transactionRequest ) => TransactionRequest

This is generally not required to be overridden, but may needed to provide custom behaviour in sub-classes.

This should return a copy of the transactionRequest, with any properties needed by call, estimateGas and populateTransaction (which is used by sendTransaction). It should also throw an error if any unknown key is specified.

The default implementation checks only valid TransactionRequest properties exist and adds from to the transaction if it does not exist.

If there is a from field it must be verified to be equal to the Signer's address.

signer . populateTransaction( transactionRequest ) => Promise< TransactionRequest >

This is generally not required to be overridden, but may needed to provide custom behaviour in sub-classes.

This should return a copy of transactionRequest, follow the same procedure as checkTransaction and fill in any properties required for sending a transaction. The result should have all promises resolved; if needed the resolveProperties utility function can be used for this.

The default implementation calls checkTransaction and resolves to if it is an ENS name, adds gasPrice, nonce, gasLimit and chainId based on the related operations on Signer.

Wallet

**new **ethers . Wallet( privateKey [ , provider ] )

Create a new Wallet instance for privateKey and optionally connected to the provider.

ethers . Wallet . createRandom( [ options = {} ] ) => Wallet

Returns a new Wallet with a random private key, generated from cryptographically secure entropy sources. If the current environment does not have a secure entropy source, an error is thrown.

Wallets created using this method will have a mnemonic.

ethers . Wallet . fromEncryptedJson( json , password [ , progress ] ) => Promise< Wallet >

Create an instance from an encrypted JSON wallet.

If progress is provided it will be called during decryption with a value between 0 and 1 indicating the progress towards completion.

ethers . Wallet . fromEncryptedJsonSync( json , password ) => Wallet

Create an instance from an encrypted JSON wallet.

This operation will operate synchronously which will lock up the user interface, possibly for a non-trivial duration. Most applications should use the asynchronous fromEncryptedJson instead.

ethers . Wallet . fromMnemonic( mnemonic [ , path , [ wordlist ] ] ) => Wallet

Create an instance from a mnemonic phrase.

If path is not specified, the Ethereum default path is used (i.e. m/44'/60'/0'/0/0).

If wordlist is not specified, the English Wordlist is used.

Properties

wallet . address => string< Address >

The address for the account this Wallet represents.

wallet . provider => Provider

The provider this wallet is connected to, which will ge used for any Blockchain Methods methods. This can be null.

Note

A Wallet instance is immutable, so if you wish to change the Provider, you may use the connect method to create a new instance connected to the desired provider.

wallet . publicKey => string< DataHexString< 65 > >

The uncompressed public key for this Wallet represents.

Methods

wallet . encrypt( password , [ options = {} , [ progress ] ] ) => Promise< string >

Encrypt the wallet using password returning a Promise which resolves to a JSON wallet.

If progress is provided it will be called during decryption with a value between 0 and 1 indicating the progress towards completion.

// Create a wallet instance from a mnemonic...
mnemonic = "announce room limb pattern dry unit scale effort smooth jazz weasel alcohol"
walletMnemonic = Wallet.fromMnemonic(mnemonic)

// ...or from a private key
walletPrivateKey = new Wallet(walletMnemonic.privateKey)

walletMnemonic.address === walletPrivateKey.address
// true

// The address as a Promise per the Signer API
walletMnemonic.getAddress()
// { Promise: '0x71CB05EE1b1F506fF321Da3dac38f25c0c9ce6E1' }

// A Wallet address is also available synchronously
walletMnemonic.address
// '0x71CB05EE1b1F506fF321Da3dac38f25c0c9ce6E1'

// The internal cryptographic components
walletMnemonic.privateKey
// '0x1da6847600b0ee25e9ad9a52abbd786dd2502fa4005dd5af9310b7cc7a3b25db'
walletMnemonic.publicKey
// '0x04b9e72dfd423bcf95b3801ac93f4392be5ff22143f9980eb78b3a860c4843bfd04829ae61cdba4b3b1978ac5fc64f5cc2f4350e35a108a9c9a92a81200a60cd64'

// The wallet mnemonic
walletMnemonic.mnemonic
// {
//   locale: 'en',
//   path: 'm/44\'/60\'/0\'/0/0',
//   phrase: 'announce room limb pattern dry unit scale effort smooth jazz weasel alcohol'
// }

// Note: A wallet created with a private key does not
//       have a mnemonic (the derivation prevents it)
walletPrivateKey.mnemonic
// null

// Signing a message
walletMnemonic.signMessage("Hello World")
// { Promise: '0x14280e5885a19f60e536de50097e96e3738c7acae4e9e62d67272d794b8127d31c03d9cd59781d4ee31fb4e1b893bd9b020ec67dfa65cfb51e2bdadbb1de26d91c' }

tx = {
  to: "0x8ba1f109551bD432803012645Ac136ddd64DBA72",
  value: utils.parseEther("1.0")
}

// Signing a transaction
walletMnemonic.signTransaction(tx)
// { Promise: '0xf865808080948ba1f109551bd432803012645ac136ddd64dba72880de0b6b3a7640000801ca0918e294306d177ab7bd664f5e141436563854ebe0a3e523b9690b4922bbb52b8a01181612cec9c431c4257a79b8c9f0c980a2c49bb5a0e6ac52949163eeb565dfc' }

// The connect method returns a new instance of the
// Wallet connected to a provider
wallet = walletMnemonic.connect(provider)

// Querying the network
wallet.getBalance();
// { Promise: { BigNumber: "42" } }
wallet.getTransactionCount();
// { Promise: 0 }

// Sending ether
wallet.sendTransaction(tx)

VoidSigner

**new **ethers . VoidSigner( address [ , provider ] ) => VoidSigner

Create a new instance of a VoidSigner for address.

voidSigner . address => string< Address >

The address of this VoidSigner.

address = "0x8ba1f109551bD432803012645Ac136ddd64DBA72"
signer = new ethers.VoidSigner(address, provider)

// The DAI token contract
abi = [
  "function balanceOf(address) view returns (uint)",
  "function transfer(address, uint) returns (bool)"
]
contract = new ethers.Contract("dai.tokens.ethers.eth", abi, signer)

// Get the number of tokens for this account
tokens = await contract.balanceOf(signer.getAddress())
// { BigNumber: "9709905125722568213383" }

//
// Pre-flight (check for revert) on DAI from the signer
//
// Note: We do not have the private key at this point, this
//       simply allows us to check what would happen if we
//       did. This can be useful to check before prompting
//       a request in the UI
//

// This will pass since the token balance is available
contract.callStatic.transfer("donations.ethers.eth", tokens)
// { Promise: true }

// This will fail since it is greater than the token balance
contract.callStatic.transfer("donations.ethers.eth", tokens.add(1))
// Error: call revert exception (method="transfer(address,uint256)", errorSignature="Error(string)", errorArgs=["Dai/insufficient-balance"], reason="Dai/insufficient-balance", code=CALL_EXCEPTION, version=abi/5.0.1)

ExternallyOwnedAccount

eoa . address => string< Address >

The Address of this EOA.

eoa . privateKey => string< DataHexString< 32 > >

The privateKey of this EOA

eoa . mnemonic => Mnemonic

Optional. The account HD mnemonic, if it has one and can be determined. Some sources do not encode the mnemonic, such as an HD extended keys.