Hi,

I have a simple next app with an api route at app/api/data/route.js

The majority of the code in the file comes from the latest node.js example in the google sheets api docs.

import { google } from 'googleapis';
import { authenticate } from '@google-cloud/local-auth';
import path from 'path';
import fs from 'fs/promises';

const SCOPES = ['https://www.googleapis.com/auth/spreadsheets.readonly'];

const TOKEN_PATH = path.join(process.cwd(), './token.json');
const CREDENTIALS_PATH = path.join(process.cwd(), './credentials.json');

async function loadSavedCredentialsIfExist() {
  try {
    const content = await fs.readFile(TOKEN_PATH);
    const credentials = JSON.parse(content);
    return google.auth.fromJSON(credentials);
  } catch (err) {
    return null;
  }
}

async function saveCredentials(client) {
  const content = await fs.readFile(CREDENTIALS_PATH);
  const keys = JSON.parse(content);
  const key = keys.installed;
  const payload = JSON.stringify({
    type: 'authorized_user',
    client_id: key.client_id,
    client_secret: key.client_secret,
    refresh_token: client.credentials.refresh_token,
  });
  await fs.writeFile(TOKEN_PATH, payload);
}

async function authorize() {
  let client = await loadSavedCredentialsIfExist();
  if (client) {
    return client;
  }
  client = await authenticate({
    scopes: SCOPES,
    keyfilePath: CREDENTIALS_PATH,
  });
  if (client.credentials) {
    await saveCredentials(client);
  }
  return client;
}

export async function GET() {

  try {
    const authClient = await authorize();
    const sheets = google.sheets({ version: 'v4', auth: authClient });

    const response = await sheets.spreadsheets.values.get({
      spreadsheetId: 'mysheetid',
      range: 'A1:S16',
    });

    const rows = response.data.values;
    return new Response(JSON.stringify(rows), {
      status: 200,
      headers: {
        'Content-Type': 'application/json',
      },
    });
  } catch (error) {
    console.error('Error accessing Sheets API', error);
    return new Response(JSON.stringify({ error: 'Error accessing Sheets API' }), {
      status: 500,
      headers: {
        'Content-Type': 'application/json',
      },
    });
  }
}

And in a regular route. Such as app/page.jsx I make a request to the API route above.

    useEffect(() => {
        fetch('/api/data')
          .then(response => response.json())
          .then(data => setSheetData(data))
          .catch(error => console.error('Error fetching sheet data:', error));
      }, []);

I get the following error.

Error accessing Sheets API Error: Cannot find module 'C:\Users\ASUS\projects\clients\illbruck-product-calculator\membrane-selector\credentials.json'
    at webpackEmptyContext (C:\Users\ASUS\myapp\.next\server\app\api\data\route.js:22:10)
    at authenticate (webpack-internal:///(rsc)/./node_modules/@google-cloud/local-auth/build/src/index.js:47:114)
    at authorize (webpack-internal:///(rsc)/./app/api/data/route.js:52:90)
    at async GET (webpack-internal:///(rsc)/./app/api/data/route.js:63:28)
    at async C:\Users\ASUS\myapp\node_modules\next\dist\compiled\next-server\app-route.runtime.dev.js:6:63251 {
  code: 'MODULE_NOT_FOUND'
}

Perhaps the error is confusing me. "Cannot find module", yet there we're not requesting a module.

The app has very little other than the above code. There are no other errors. Is my implementation wrong for next.js?