Proper way to interact with BPF_LOADER_PROGRAM in Web3JS

Question

What is the expected way to interact with the BPFUpgradeLoader using the Solana Web3 JS SDK? It appears the web3.BPF_LOADER_PROGRAM_ID is marked as deprecated, but it offers no clear alternative.

What is the proper way to do this? I needed to change the upgrade authority from one public key to another as part of a script and wanted to do this in the most idiomatic way possible. I don't want to ignore the deprecated notice and send a transaction to the loader program. Is there a better way to do this?

Answer 1

The @solana/web3.js v2 compatible clients for the loader programs can be found in the @solana-program org. Presently they are:

• @solana-program/loader-v3
• @solana-program/loader-v4

You can use the v3 loader to update the authority.

import { getSetAuthorityInstruction } from '@solana-program/loader-v3';

// Create a `TransactionSigner` instance. This is one way.
// There are many others: https://tinyurl.com/4ez3xyvh
const currentAuthoritySigner = await createSignerFromKeyPair(currentAuthorityKeyPair);

// Create the 'set authority' instruction for use in your transaction.
const setAuthorityInstruction = getSetAuthorityInstruction({
    bufferOrProgramDataAccount: programAddress,
    currentAuthority: currentAuthoritySigner,
    newAuthority: newAuthorityAddress,
});