Skeleton code on using shopify-api for nodejs

Shopify Apps
1

I am trying to develop an app to query a store’s orders. The app is a public app ie will be installed by many stores but I am currently testing it on a development store.

The documentation is somewhat confusing and is very limited with no proper examples. Therefore, I wanted to report this here with the hope of getting some guidance.

Below is my app.js for a node application using “@shopify/shopify-api”: “^9.3.1”

require('@shopify/shopify-api/adapters/node');
const { shopifyApi, Session } = require('@shopify/shopify-api');

const shopify = shopifyApi({
    apiKey: 'The Client ID that I got from partners panel',
    apiSecretKey: 'The Client key that I got from partners panel',
    scopes: ['read_customers', 'read_orders'],
    hostName: 'https://XXXXXXXXX.ngrok-free.app',
});

const sessionId = shopify.session.getOfflineId("mystore_address.myshopify.com");

const session = new Session({
    id: sessionId,
    shop: "mystore_address.myshopify.com",
    isOnline: false,
    accessToken: 'permanentAccessToken',
});

const client = new shopify.clients.Rest({ session: session });

client.get({
    path: 'products',
}).then((val) => {
    console.log(val);
});

I keep getting the following example and I would be grateful if you could share any guidance you might have.

errors: ‘[API] Invalid API key or access token (unrecognized login or wrong password)’