getTokenAccountOwner.ts

import {
  Connection,
  ParsedInstruction,
  ParsedTransactionWithMeta,
  PartiallyDecodedInstruction,
  PublicKey,
} from "@solana/web3.js";
import { Maybe } from "formfn-shared/dist/types/UtilityTypes";
import { TOKEN_PROGRAM_ID } from "@solana/spl-token";

type TokenAccountInfo = {
  delegate: string;
  delegatedAmount: {
    amount: string;
    decimals: number;
    uiAmount: number;
    uiAmountString: string;
  };
  isNative: boolean;
  mint: string;
  owner: string;
  state: string;
  tokenAmount: {
    amount: string;
    decimals: number;
    uiAmount: number;
    uiAmountString: string;
  };
};

async function getTokenAccountInfo(
  connection: Connection,
  tokenAccount: PublicKey
): Promise<Maybe<TokenAccountInfo>> {
  const parsedAccountInfo = await connection.getParsedAccountInfo(tokenAccount);

  const data = parsedAccountInfo?.value?.data;

  if (data != null && "parsed" in data) {
    return data.parsed.info;
  }

  return null;
}

function getAllInnerIxs(parsedTx: ParsedTransactionWithMeta) {
  return parsedTx.meta?.innerInstructions?.reduce(
    (acc: Array<ParsedInstruction | PartiallyDecodedInstruction>, currVal) => [
      ...acc,
      ...currVal.instructions,
    ],
    []
  );
}

function isInitializeAccountIx(
  ix: ParsedInstruction | PartiallyDecodedInstruction,
  account?: string
) {
  return (
    ix.programId.toString() === TOKEN_PROGRAM_ID.toString() &&
    (ix as ParsedInstruction).parsed?.type === "initializeAccount" &&
    (account == null ||
      (ix as ParsedInstruction).parsed?.info?.account?.toString() === account)
  );
}

export default async function getTokenAccountOwner(
  connection: Connection,
  tokenAccount: PublicKey
): Promise<Maybe<string>> {
  // First, try to get the token account info. May return null if account has been closed.
  const tokenAccountInfo = await getTokenAccountInfo(connection, tokenAccount);
  if (tokenAccountInfo != null) {
    return tokenAccountInfo.owner;
  }

  const signatures = await connection.getConfirmedSignaturesForAddress2(
    tokenAccount
  );

  if (signatures.length === 0) {
    return null;
  }

  // Parse the first tx, which should have created the token account
  const firstSignature = signatures[signatures.length - 1];
  const parsedTx = await connection.getParsedTransaction(
    firstSignature.signature,
    "confirmed"
  );

  if (parsedTx == null) {
    return null;
  }

  const ixs = parsedTx.transaction.message.instructions;
  const allInnerIxs = getAllInnerIxs(parsedTx) ?? [];

  const initializeAccountIx = [...ixs, ...allInnerIxs].find((ix) =>
    isInitializeAccountIx(ix, tokenAccount.toString())
  );

  if (initializeAccountIx == null) {
    return null;
  }

  return (
    initializeAccountIx as ParsedInstruction
  ).parsed?.info?.owner?.toString();
}