Easiest Way to Create Google OAuth2Client in Node.js Backend

Published 2023-05-01

OAuth 2.0 is an open standard for authentication and authorization, which allows third-party applications to access user data from various service providers without the need for the user to share their username and password. Google provides a comprehensive set of APIs and tools to implement OAuth 2.0 authentication for its services.

In this post, I will be sharing how you can easily create an OAuth2Client in the backend using google-auth-library package.

Step 1: Install the `google-auth-library` package

The first step is to install the google-auth-library package using the following command:

npm install google-auth-library

Step 2: Import the OAuth2Client class

Next, we need to import the OAuth2Client class from the google-auth-library package. We can do this using the following code:

import { OAuth2Client } from 'google-auth-library';

Step 3: Create a new OAuth2Client instance

To create a new OAuth2Client instance, we need to provide the client ID and client secret obtained from the Google Cloud Console. We can create a new instance of the OAuth2Client class using the following code:

const CLIENT_ID = 'your-client-id';
const CLIENT_SECRET = 'your-client-secret';

const oauth2Client = new OAuth2Client({
  clientId: CLIENT_ID,
  clientSecret: CLIENT_SECRET,
});

Step 4: Assign the Credential to OAuth2Client instance

To use the Google Service APIs, we need to assign the credential to the OAuth2Client instance.

const refresh_token = 'refresh-token'; // Required.
const access_token = 'access_token'; // Optional
const expiry_date = 1682921737269; // Optional

oauth2Client.setCredentials({
  refresh_token,
  access_token,
  expiry_date,
});

Conclusion

There you go. Now you have the OAuth2Client instance. Next, we will be using the OAuth2Client here to interact with the Google Services API such as Google Sheets API, Google Drive API and etc.