This method allows you to fetch a token with its mint and metadata (covers Token Extensions and Metaplex)

fetch-token.ts

import { Metaplex } from "@metaplex-foundation/js";
import {
  getMint,
  getTokenMetadata as getToken2022Metadata,
  Mint,
} from "@solana/spl-token";
import { PublicKey } from "@solana/web3.js";
import { config } from "./config";

// Generalized Token metadata interface
interface TokenMetadataResult {
  symbol: string;
  name?: string;
  uri?: string;
}

// Token object combining Mint and metadata
interface Token {
  mint: Mint;
  metadata: TokenMetadataResult;
}

export async function fetchToken(mint: PublicKey): Promise<Token> {
  const { connection } = config;

  // Fetch Mint info
  const mintInfo = await getMint(connection, mint);

  // Special case for Wrapped SOL
  if (mint.toBase58() === "So11111111111111111111111111111111111111112") {
    return {
      mint: mintInfo,
      metadata: { symbol: "SOL" },
    };
  }

  // Try Token-2022 metadata (on-chain extensions)
  const token2022Metadata = await getToken2022Metadata(connection, mint).catch(
    () => null
  );
  if (token2022Metadata?.symbol) {
    return {
      mint: mintInfo,
      metadata: {
        symbol: token2022Metadata.symbol,
        name: token2022Metadata.name,
        uri: token2022Metadata.uri,
      },
    };
  }

  // Try Metaplex metadata (off-chain PDA)
  const metaplex = new Metaplex(connection);
  const metaplexMetadata = await metaplex
    .nfts()
    .findByMint({ mintAddress: mint })
    .catch(() => null);
  if (metaplexMetadata?.json?.symbol) {
    return {
      mint: mintInfo,
      metadata: {
        symbol: metaplexMetadata.json.symbol,
        name: metaplexMetadata.json.name,
        uri: metaplexMetadata.uri,
      },
    };
  }

  // Fallback to truncated mint
  return {
    mint: mintInfo,
    metadata: { symbol: mint.toBase58().slice(0, 6) },
  };
}