Creating a lookup table with web3.js

Question

I'm running into an error with transactions overruning UInt8Array buffer, and I see that I need to save space using versioned transactions and address lookup tables.

How can I create one using the @solana/web3.js library? Ideally I'd like to pass in keys and create it a separate transaction.

Answer 1

You can use AddressLookupTableProgram.createLookupTable to create an LUT and then AddressLookupTableProgram.extendLookupTable to add addresses to it. Here's a quick snippet:

export const createLookupTable = async (
  wallet: NodeWallet,
  connection: web3.Connection,
  keys: string[]
) => {
  const slot = await connection.getSlot();

  const [lookupTableInst, lookupTableAddress] =
    web3.AddressLookupTableProgram.createLookupTable({
      authority: wallet.publicKey,
      payer: wallet.publicKey,
      recentSlot: slot,
    });

  const extendInstruction = web3.AddressLookupTableProgram.extendLookupTable({
    payer: wallet.publicKey,
    authority: wallet.publicKey,
    lookupTable: lookupTableAddress,
    addresses: keys.map((key) => new web3.PublicKey(key)),
  });

  return {
    lutIx: lookupTableAddress,
    createLutIx: lookupTableInst,
    extendIx: extendInstruction,
  }
};

Additionally, here's a full gist outlining different situations for creating lookup tables: https://gist.github.com/joeymeere/b38153fb478a5c19f1ea6a9e51c8f185