How to fetch data using wagmi without user wallet?

[Al3xGROS]

I created a NextJS project with Wagmi and Rainbowkit. When no wallet is connected, in private navigation, for example, the useReadContract hooks return errors.

So I wanted to know if reading from a contract without being connected was possible.

I tried to use the readContract action from @wagmi/core but it still does not work.

Thanks.

[tmm]

Yes, it's possible. Unless you share some code with what you are running into, unfortunately no one can help.

[Al3xGROS]

Hello @tmm,

Sorry I've been busy.

Here is the code:

• config.ts:

import { http, createConfig } from "wagmi";
import { mainnet, sepolia } from "wagmi/chains";

export const config = createConfig({
  chains: [sepolia, avalanche],
  transports: {
    [mainnet.id]: http(),
    [sepolia.id]: http(),
  },
});

• data.ts:

import { readContract } from "wagmi/actions";
import { config } from "./config";

export const abi = [
  {
    type: "function",
    name: "balanceOf",
    stateMutability: "view",
    inputs: [{ name: "account", type: "address" }],
    outputs: [{ type: "uint256" }],
  },
  {
    type: "function",
    name: "totalSupply",
    stateMutability: "view",
    inputs: [],
    outputs: [{ name: "supply", type: "uint256" }],
  },
] as const;

export async function fetchSupply() {
  const result = await readContract(config, {
    abi,
    address: "0x6b175474e89094c44da98b954eedeac495271d0f",
    functionName: "totalSupply",
    args: [],
  });
  console.log(result);
  return result;
}

• Supply.tsx:

import { fetchSupply } from "../lib/data";

export default async function Supply() {
  const supply = await fetchSupply();

  return (
    <main>
      <div className="text-white text-xl">{Number(supply)}</div>
    </main>
  );
}

• page.tsx:

import Supply from "./ui/Supply";

export default function Home() {
  return (
    <main className="flex min-h-screen flex-col items-center justify-between p-24">
      <Supply />
    </main>
  );
}

And the error I get is:

Error: The contract function "totalSupply" returned no data ("0x").

This could be due to any of the following:
  - The contract does not have the function "totalSupply",
  - The parameters passed to the contract function may be invalid, or
  - The address is not a contract.
 
Contract Call:
  address:   0x6b175474e89094c44da98b954eedeac495271d0f
  function:  totalSupply()

Docs: https://viem.sh/docs/contract/readContract
Version: 2.21.15

Am I missing something?