utils.ts

import { utils } from "@project-serum/anchor";
import { Keypair } from "@solana/web3.js";

export const keypairFrom = (s: string | undefined, n?: string): Keypair => {
  if (!s) throw `${n ?? "keypair"} is undefined`;
  try {
    if (s.includes("[")) {
      return Keypair.fromSecretKey(
        Buffer.from(
          s
            .replace("[", "")
            .replace("]", "")
            .split(",")
            .map((c) => parseInt(c))
        )
      );
    } else {
      return Keypair.fromSecretKey(utils.bytes.bs58.decode(s));
    }
  } catch (e) {
    try {
      return Keypair.fromSecretKey(
        Buffer.from(
          JSON.parse(
            require("fs").readFileSync(s, {
              encoding: "utf-8",
            })
          )
        )
      );
    } catch (e) {
      process.stdout.write(`${n ?? "keypair"} is not valid keypair`);
      process.exit(1);
    }
  }
};