Token accounts for owner

token_account_helper.ts

import * as BufferLayout from "buffer-layout";
import {
  AccountInfo,
  ASSOCIATED_TOKEN_PROGRAM_ID,
  Token,
  TOKEN_PROGRAM_ID,
  u64,
} from "@solana/spl-token";
import { Connection, PublicKey } from "@solana/web3.js";
import { BN } from "bn.js";

export const getAssociatedTokenAccountAddress = async (
  walletAddress: PublicKey,
  mint: PublicKey
) =>
  Token.getAssociatedTokenAddress(
    ASSOCIATED_TOKEN_PROGRAM_ID,
    TOKEN_PROGRAM_ID,
    mint,
    walletAddress
  );

export async function getOwnedAssociatedTokenAccounts(
  connection: Connection,
  publicKey: PublicKey
) {
  let filters = getOwnedAccountsFilters(publicKey);
  let resp = await connection.getProgramAccounts(TOKEN_PROGRAM_ID, {
    commitment: connection.commitment,
    filters,
  });

  const accsParsed: AccountInfoPartial[] = resp.map(({ pubkey, account }) => {
    return { ...parseTokenAccountData(account.data), address: pubkey };
  });

  return (
    await Promise.all(
      accsParsed
        // @ts-ignore
        .map(async (ta) => {
          const ata = await Token.getAssociatedTokenAddress(
            ASSOCIATED_TOKEN_PROGRAM_ID,
            TOKEN_PROGRAM_ID,
            ta.mint,
            publicKey
          );
          return { ta, ata };
        })
    )
  )
    .filter(({ ta, ata }) => ta.address.equals(ata))
    .map(({ ta }) => ta);
}

const ACCOUNT_LAYOUT = BufferLayout.struct([
  BufferLayout.blob(32, "mint"),
  BufferLayout.blob(32, "owner"),
  BufferLayout.nu64("amount"),
  BufferLayout.blob(93),
]);

export type AccountInfoPartial = Pick<
  AccountInfo,
  "address" | "amount" | "mint" | "owner"
>;

export function parseTokenAccountData(data: Buffer): AccountInfoPartial {
  // @ts-ignore
  let { mint, owner, amount } = ACCOUNT_LAYOUT.decode(data);
  // @ts-ignore
  return {
    mint: new PublicKey(mint),
    owner: new PublicKey(owner),
    amount: new BN(amount),
  };
}

function getOwnedAccountsFilters(publicKey: PublicKey) {
  return [
    {
      memcmp: {
        // @ts-ignore
        offset: ACCOUNT_LAYOUT.offsetOf("owner"),
        bytes: publicKey.toBase58(),
      },
    },
    {
      dataSize: ACCOUNT_LAYOUT.span,
    },
  ];
}