Minting

To mint from a Candy Machine via a configured Candy Guard account, you may use the mintV2 function and provide the mint address and update authority of the collection NFT the minted NFT will belong to. A minter signer and payer signer may also be provided but they will default to Umi's identity and payer respectively.

As mentioned above, you may need to increase the compute unit limit of the transaction to ensure the mintV2 instruction is successful. You may do this by using the setComputeUnitLimit helper function on the mpl-toolbox Umi library as illustrated in the code snippet below.

If you want to mint pNFT (e.g. for royalty enforcement) and have your Candy Machine set up accordingly you will have to add the tokenStandard field. By default NonFungible is used. If you fetched the Candy Machine before you could use candyMachine.tokenStandard, otherwise you have to assign it yourself by using tokenStandard: TokenStandard.ProgrammableNonFungible from @metaplex-foundation/mpl-token-metadata.

import { mintV2 } from '@metaplex-foundation/mpl-candy-machine'
import { setComputeUnitLimit } from '@metaplex-foundation/mpl-toolbox'
import { transactionBuilder, generateSigner } from '@metaplex-foundation/umi'

const nftMint = generateSigner(umi)
await transactionBuilder()
  .add(setComputeUnitLimit(umi, { units: 800_000 }))
  .add(
    mintV2(umi, {
      candyMachine: candyMachine.publicKey,
      nftMint,
      collectionMint: collectionNft.publicKey,
      collectionUpdateAuthority: collectionNft.metadata.updateAuthority,
      tokenStandard: candyMachine.tokenStandard,
    })
  )
  .sendAndConfirm(umi)

Note that the mintV2 instruction takes care of creating the Mint and Token accounts for us by default and will set the NFT owner to the minter. If you wish to create these yourself beforehand, you may simply give the NFT mind address as a public key instead of a signer. Here's an example using the createMintWithAssociatedToken function from the mpl-toolbox Umi library:

import { mintV2 } from '@metaplex-foundation/mpl-candy-machine'
import {
  createMintWithAssociatedToken,
  setComputeUnitLimit,
} from '@metaplex-foundation/mpl-toolbox'
import { transactionBuilder, generateSigner } from '@metaplex-foundation/umi'

const nftMint = generateSigner(umi)
const nftOwner = generateSigner(umi).publicKey
await transactionBuilder()
  .add(setComputeUnitLimit(umi, { units: 800_000 }))
  .add(createMintWithAssociatedToken(umi, { mint: nftMint, owner: nftOwner }))
  .add(
    mintV2(umi, {
      candyMachine: candyMachine.publicKey,
      nftMint: nftMint.publicKey,
      collectionMint: collectionNft.publicKey,
      collectionUpdateAuthority: collectionNft.metadata.updateAuthority,
    })
  )
  .sendAndConfirm(umi)

In the rare event that you wish to mint directly from the Candy Machine Core program, you may use the mintFromCandyMachineV2 function instead. This function requires the mint authority of the candy machine to be provided as a signer and accepts an explicit nftOwner attribute.

import { mintFromCandyMachineV2 } from '@metaplex-foundation/mpl-candy-machine'
import { setComputeUnitLimit } from '@metaplex-foundation/mpl-toolbox'
import { transactionBuilder, generateSigner } from '@metaplex-foundation/umi'

const nftMint = generateSigner(umi)
const nftOwner = generateSigner(umi).publicKey
await transactionBuilder()
  .add(setComputeUnitLimit(umi, { units: 800_000 }))
  .add(
    mintFromCandyMachineV2(umi, {
      candyMachine: candyMachine.publicKey,
      mintAuthority: umi.identity,
      nftOwner,
      nftMint,
      collectionMint: collectionNft.publicKey,
      collectionUpdateAuthority: collectionNft.metadata.updateAuthority,
    })
  )
  .sendAndConfirm(umi)

API References: mintV2, mintFromCandyMachineV2

When minting via the Umi library, you may use the mintArgs attribute to provide the required Mint Settings.

Here’s an example using the Third Party Signer guard which requires an additional signer and the Mint Limit guard which keeps track of how many times a wallet minted from the Candy Machine.

import {
  some,
  generateSigner,
  transactionBuilder,
} from '@metaplex-foundation/umi'
import { create, mintV2 } from '@metaplex-foundation/mpl-candy-machine'
import { setComputeUnitLimit } from '@metaplex-foundation/mpl-toolbox'

// Create a Candy Machine with guards.
const thirdPartySigner = generateSigner()
await create(umi, {
  // ...
  guards: {
    thirdPartySigner: some({ signer: thirdPartySigner.publicKey }),
    mintLimit: some({ id: 1, limit: 3 }),
  },
}).sendAndConfirm(umi)

// Mint from the Candy Machine.
const nftMint = generateSigner(umi)
await transactionBuilder()
  .add(setComputeUnitLimit(umi, { units: 800_000 }))
  .add(
    mintV2(umi, {
      candyMachine: candyMachine.publicKey,
      nftMint,
      collectionMint: collectionNft.publicKey,
      collectionUpdateAuthority: collectionNft.metadata.updateAuthority,
      mintArgs: {
        thirdPartySigner: some({ signer: thirdPartySigner }),
        mintLimit: some({ id: 1 }),
      },
    })
  )
  .sendAndConfirm(umi)

API References: mintV2, DefaultGuardSetMintArgs

When minting from a Candy Machine using guard groups, the label of the group we want to select must be provided via the group attribute.

Additionally, the Mint Settings for the Resolved Guards of that group may be provided via the mintArgs attribute.

Here is how we would use the Umi library to mint from the example Candy Machine described above.

// Create a Candy Machine with guards.
const thirdPartySigner = generateSigner()
await create(umi, {
  // ...
  guards: {
    botTax: some({ lamports: sol(0.001), lastInstruction: true }),
    thirdPartySigner: some({ signer: thirdPartySigner.publicKey }),
    startDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
  },
  groups: [
    {
      label: 'nft',
      guards: {
        nftPayment: some({ requiredCollection, destination: nftTreasury }),
        startDate: some({ date: dateTime('2022-10-18T16:00:00Z') }),
      },
    },
    {
      label: 'public',
      guards: {
        solPayment: some({ lamports: sol(1), destination: solTreasury }),
      },
    },
  ],
}).sendAndConfirm(umi)

// Mint from the Candy Machine.
const nftMint = generateSigner(umi)
await transactionBuilder()
  .add(setComputeUnitLimit(umi, { units: 800_000 }))
  .add(
    mintV2(umi, {
      candyMachine: candyMachine.publicKey,
      nftMint,
      collectionMint: collectionNft.publicKey,
      collectionUpdateAuthority: collectionNft.metadata.updateAuthority,
      group: some('nft'),
      mintArgs: {
        thirdPartySigner: some({ signer: thirdPartySigner }),
        nftPayment: some({
          mint: nftFromRequiredCollection.publicKey,
          destination: nftTreasury,
          tokenStandard: TokenStandard.NonFungible,
        }),
      },
    })
  )
  .sendAndConfirm(umi)

API References: mintV2, DefaultGuardSetMintArgs