Utils

Many utility and convenience functions are defined in utils.ts

The utility functions can roughly be split into 3 categories:

• Type Constructors
• Hash Utilities
• EIP-712 Utilities
• Miscellaneous

Type Constructors

There are a number of Types that are necessary to interact with a Zora instance. The type constructors accept input, perform basic validation on the input, and return the properly formatted Zora Type.

constructMediaData

• Accepts the arguments for constructing MediaData type.
• Validates that the URIs begins with https://.
• Validates that the hashes are exactly 32 bytes in length.

import { constructMediaData, sha256FromBuffer } from '@zoralabs/zdk'

const contentHash = await sha256FromBuffer(Buffer.from('some content'))
const metadataHash = await sha256FromBuffer(Buffer.from('some metadata'))

const mediaData = constructMediaData(
  'https://token.com',
  'https://metadata.com',
  contentHash,
  metadataHash
)

constructAsk

• Parses and Validates the currency address to ensure its a valid Ethereum Address

import { constructAsk, Decimal } from '@zoralabs/zdk'

const dai = '0x6B175474E89094C44Da98b954EedeAC495271d0F'
const decimal100 = Decimal.new(100)
const ask = constructAsk(dai, decimal100.value)

constructBid

• Parses and Validates the bidder, recipient, and currency addresses.
• Rounds the SellOnShare to 4 decimals of precision

import { constructBid, Decimal } from '@zoralabs/zdk'

const dai = '0x6B175474E89094C44Da98b954EedeAC495271d0F'
const decimal100 = Decimal.new(100)
const bidder = '0xf13090cC20613BF9b5F0b3E6E83CCAdB5Cd0FbD5'
const bid = constructBid(dai, decimal100.value, bidder, bidder, 33.3333)

constructBidShares

• Accepts number args, converts them to ethers BigNumber type with 18 decimals of precision.
• Performs validation that the BigNumber representations sum to 100 in BigNumber form.

import { constructBidShares } from '@zoralabs/zdk'

const bidShares = constructBidShares(10, 90, 0)

Hashing Utilities

All pieces of media minted on the Zora Protocol must etch a sha56 hash of both its content and metadata onto the blockchain. As such it is important developers interacting with Zora have reliable ways to create and verify hashes of data of all types of sizes.

sha256FromBuffer

Create a sha256 from a Buffer object

import { sha256FromBuffer } from '@zoralabs/zdk'
import { promises as fs } from 'fs'


const buf = await fs.readFile('path/to/file')
const hash = sha256FromBuffer(buf)

const otherBuffer = Buffer.from('someContent')
const otherHash = sha256FromBuffer(otherBuffer)

sha256FromHexString

Create a sha256 hash from a hex string. Hex string must be prefixed with 0x

import { sha256FromHexString } from '@zoralabs/zdk'

const buf = Buffer.from('someContent')
const hexString = '0x'.concat(buf.toString('hex'))
const hash = sha256FromHexString(hexString)

sha256FromFile

Create a sha256 hash from a local file This is most useful for the hashing of large files. It uses a readStream to load bits into memory via a buffer and construct a hash as it consumes the contents of the file.

import { sha256FromFile } from '@zoralabs/zdk'

const hash = await sha256FromFile('path/to/file', 16 * 1024)

EIP-712 Utilities

signPermitMessage

Permit was specified as an extension of ERC-20 standard to allow for users to issue approval to accounts without needing ETH.

We have extended it further to be used for the Zora Protocol, so that users can delegate approvals to orther smart contracts to perform actions that approved users can do such as:

• setAsk
• acceptBid
• updateContentURI
• updateMetadataURI
• transfer

For now, the signer must be an ethers Wallet object. But soon we will support any Signer.

import { JsonRpcProvider } from '@ethersproject/providers'
import { generatedWallets } from '@zoralabs/core/dist/utils'
import {
  Zora,
  signPermitMessage,
} from 'zoralabs/zdk'

const provider = new JsonRpcProvider()
const [mainWallet, otherWallet] = generatedWallets(provider)
const rinkebyZora = new Zora(mainWallet, 4)
const deadline = Math.floor(new Date().getTime() / 1000) + 60 * 60 * 24 // 24 hours
const domain = rinkebyZora.eip712Domain()
const eipSig = await signPermitMessage(
  mainWallet,
  otherWallet.address,
  0, // mediaId
  0, // nonce
  deadline,
  domain
)

signMintWithSigMessage

We extended EIP-712 to allow for creators to mint without needing ETH. A user can sign a mintWithSig message and use a trusted relayer to relay the transaction and mint on their behalf.

import { JsonRpcProvider } from '@ethersproject/providers'
import { generatedWallets } from '@zoralabs/core/dist/utils'
import {
  Zora,
  sha256FromBuffer,
  signMintWithSigMessage,
  Decimal,
  constructMediaData,
  constructBidShares
} from 'zoralabs/zdk'

const provider = new JsonRpcProvider()
const [mainWallet, otherWallet] = generatedWallets(provider)
const rinkebyZora = new Zora(otherWallet, 4)

const contentHash = await sha256FromBuffer(Buffer.from('some content'))
const metadataHash = await sha256FromBuffer(Buffer.from('some metadata'))
const contentURI = 'https://token.com'
const metadataURI = 'https://metadata.com'

const mediaData = constructMediaData(
  contentURI,
  metadataURI,
  contentHash,
  metadataHash
)
const bidShares = constructBidShares(10, 90, 0)
const deadline = Math.floor(new Date().getTime() / 1000) + 60 * 60 * 24 // 24 hours
const domain = rinkebyZora.eip712Domain()
const nonce = await rinkebyZora.fetchMintWithSigNonce(mainWallet.address)
const eipSig = await signMintWithSigMessage(
  mainWallet,
  contentHash,
  metadataHash,
  Decimal.new(10).value,
  nonce.toNumber(),
  deadline,
  domain
)

recoverSignatureFromPermit

Recover the address of the signing private key of a Permit message

import { JsonRpcProvider } from '@ethersproject/providers'
import { generatedWallets } from '@zoralabs/core/dist/utils'
import {
  Zora,
  signPermitMessage,
  recoverSignatureFromPermit,
} from 'zoralabs/zdk'

const provider = new JsonRpcProvider()
const [mainWallet, otherWallet] = generatedWallets(provider)
const zora = new Zora(provider, 4)
const deadline = Math.floor(new Date().getTime() / 1000) + 60 * 60 * 24 // 24 hours
const domain = zora.eip712Domain()
const eipSig = await signPermitMessage(
  mainWallet,
  otherWallet.address,
  1,
  1,
  deadline,
  domain
)

const recovered = await recoverSignatureFromPermit(
  otherWallet.address,
  1,
  1,
  deadline,
  domain,
  eipSig
)

if (recovered.toLowerCase() != mainWallet.address.toLowerCase()) {
  console.log('Unable to Validate Signature')
} else {
  console.log('Signature Validated')
}

recoverSignatureFromMintWithSig

Recover the address of the signing private key of a mintWithSig message

import { JsonRpcProvider } from '@ethersproject/providers'
import { generatedWallets } from '@zoralabs/core/dist/utils'
import {
  Zora,
  sha256FromBuffer,
  signMintWithSigMessage,
  recoverSignatureFromMintWithSig,
  Decimal
} from 'zoralabs/zdk'

const provider = new JsonRpcProvider()
const [mainWallet] = generatedWallets(provider)
const rinkebyZora = new Zora(provider, 4)
const deadline = Math.floor(new Date().getTime() / 1000) + 60 * 60 * 24 // 24 hours
const domain = rinkebyZora.eip712Domain()

const contentHash = await sha256FromBuffer(Buffer.from('some content'))
const metadataHash = await sha256FromBuffer(Buffer.from('some metadata'))

const eipSig = await signMintWithSigMessage(
  mainWallet,
  contentHash,
  metadataHash,
  Decimal.new(10).value,
  1,
  deadline,
  domain
)

const recovered = await recoverSignatureFromMintWithSig(
  contentHash,
  metadataHash,
  Decimal.new(10).value,
  2,
  deadline,
  domain,
  eipSig
)

if (recovered.toLowerCase() != mainWallet.address.toLowerCase()) {
  console.log('Unable to Validate Signature')
} else {
  console.log('Signature Validated')
}

Miscellaneous

approveERC20

Approves the specified amount of an ERC20 for the spender address to spend from the wallet address.

import { approveERC20, Decimal } from '@zoralabs/zdk'
import { Wallet } from 'ethers'
import { JsonRpcProvider } from '@ethersproject/providers'

const provider = new JsonRpcProvider() // must provide a uri to access an ethereum node, defaults to localhost:8545
const dai = '0x6B175474E89094C44Da98b954EedeAC495271d0F'
const wallet = Wallet.createRandom().connect(provider) // creates random wallet and connects to ethereum provider
const spenderWallet = Wallet.createRandom().connect(provider) // creates another random wallet

// before calling approveERC20 on wallet, ensure it has a balance of the currency
// in this example wallet is a randomly created wallet so does not contain a balance of dai
await approveERC20(wallet, dai, spenderWallet.address, Decimal.new(10).value)

isURIHashVerified

Returns the verified status of a uri. A uri is only considered verified if its content hashes to its expected hash

import { isURIHashVerified } from '@zoralabs/zdk'

const uri = 'https://ipfs.io/ipfs/QmRA3NWM82ZGynMbYzAgYTSXCVM14Wx1RZ8fKP42G6gjgj'
const expectedHash = '0xb1674191a88ec5cdd733e4240a81803105dc412d6c6708d53ab94fc248f4f553'

const verified = await isURIHashVerified(uri, expectedHash)

isMediaDataVerified

Returns the verified status of some MediaData. MediaData is only considered verified if the content of its URIs hash to their respective hash

import { constructMediaData, isMediaDataVerified } from '@zoralabs/zdk'

const contentURI = 'https://ipfs.fleek.co/ipfs/bafybeiacyrrjel6qq2mdv6to6fvbzsg64y3g4kbp32h55zfmesx2oe7cwi'
const contentHash = '0x4646793fb9d195cd2760c8c11538b5f7b97fd456fbe8a1226a997ed49d6f944d'
const metadataURI = 'https://ipfs.fleek.co/ipfs/bafybeifvmzeyggdi36igqjiub5bq6vbpn5ebihxgqjbrk5ibqculk4upoy'
const metadataHash = '0x95a1b4039d0582a6bf5c3fb57893cf4b57a9a9b9986bb7cc89f3489e0b702fdb'

const mediaData = constructMediaData(contentURI, metadataURI, contentHash, metadataHash)
const verified = isMediaDataVerified(mediaData)

wrapETH

Calls the deposit function on the specified weth contract address, wrapping the amount of eth to weth for the wallet

import { wrapETH, WETH_MAINNET, Decimal } from '@zoralabs/zdk'
import { Wallet } from 'ethers'
import { JsonRpcProvider } from '@ethersproject/providers'

const provider = new JsonRpcProvider("<infura / alchemy mainnet node url>") // you can pass a url to your ethereum node, it will default to localhost:8545 for local blockchain development
const wallet =  Wallet.fromMnemoic('<your mneumonic>').connect(provider)
await wrapETH(wallet, WETH_MAINNET, Decimal.new(1).value) // wrap 1 eth to weth for wallet

unwrapWETH

Calls the withdraw function on the specified weth contract address, unwrapping amount of weth to eth for wallet

import { unwrapWETH, WETH_MAINNET, Decimal } from '@zoralabs/zdk'
import { Wallet } from 'ethers'
import { JsonRpcProvider } from '@ethersproject/providers'

const provider = new JsonRpcProvider("<infura / alchemy mainnet node url>") // you can pass a url to your ethereum node, it will default to localhost:8545 for local blockchain development
const wallet =  Wallet.fromMnemoic('<your mneumonic>').connect(provider)
await unwrapWETH(wallet, WETH_MAINNET, Decimal.new(1).value) // wrap 1 eth to weth for wallet