Multisig Transactions

import { MultiSigPublicKey } from '@mysten/sui/multisig';
import { Ed25519Keypair } from '@mysten/sui/keypairs/ed25519';

// Create keypairs for participants
const keypair1 = new Ed25519Keypair();
const keypair2 = new Ed25519Keypair();
const keypair3 = new Ed25519Keypair();

// Create 2-of-3 multisig
const multisigPublicKey = MultiSigPublicKey.fromPublicKeys({
  threshold: 2,
  publicKeys: [
    { publicKey: keypair1.getPublicKey(), weight: 1 },
    { publicKey: keypair2.getPublicKey(), weight: 1 },
    { publicKey: keypair3.getPublicKey(), weight: 1 },
  ],
});

const multisigAddress = multisigPublicKey.toSuiAddress();
console.log('Multisig address:', multisigAddress);

import { Transaction } from '@mysten/sui/transactions';

const tx = new Transaction();
tx.transferObjects([tx.splitCoins(tx.gas, [1000000])], recipient);
tx.setSender(multisigAddress);

// Build transaction
const txBytes = await tx.build({ client });

// Each participant signs
const sig1 = await keypair1.signTransaction(txBytes);
const sig2 = await keypair2.signTransaction(txBytes);

// Combine signatures
const combinedSignature = multisigPublicKey.combinePartialSignatures([
  sig1.signature,
  sig2.signature,
]);

// Execute with multisig
const result = await client.executeTransactionBlock({
  transactionBlock: txBytes,
  signature: combinedSignature,
});

// 3-of-5 with weighted keys
const multisigPublicKey = MultiSigPublicKey.fromPublicKeys({
  threshold: 3,
  publicKeys: [
    { publicKey: adminKey, weight: 2 },   // Admin has 2 votes
    { publicKey: member1Key, weight: 1 },
    { publicKey: member2Key, weight: 1 },
    { publicKey: member3Key, weight: 1 },
  ],
});