How I Handle Authentication in My Chrome Extension

Summary

This video explains how to implement Google OAuth authentication in a web application with a frontend and backend server. It covers the process of verifying the Google ID token, creating or identifying a user in the database, and setting a session cookie for persistent authentication. The video also highlights how the website and browser extension share the same authentication session, ensuring synchronization between the two. Lastly, it touches on the logout flow and future considerations for using Google APIs, inviting feedback from viewers for potential improvements.

Takeaways

• 😀 The authentication flow uses Google ID tokens to authenticate users on both the website and browser extension.
• 😀 The server validates the Google ID token using a middleware, ensuring the user's identity and extracting relevant user data (e.g., email, profile image).
• 😀 Once authenticated, a session cookie is set, containing the user's MongoDB ID, which is used for future requests to maintain the session.
• 😀 The session cookie is automatically sent with each request when the `credentials: include` option is set, ensuring smooth session management.
• 😀 The website and extension share the same session logic, so users are synchronized between both platforms once logged in.
• 😀 The extension doesn't require its own authentication flow or cookie management, as it uses the same session cookie from the website.
• 😀 A user is logged out from both the website and extension simultaneously when the session cookie is cleared through the logout endpoint.
• 😀 The current system only uses Google ID tokens for authentication, with no need for access or refresh tokens at this point.
• 😀 If needed in the future, the system can be extended to handle access and refresh tokens for further interaction with Google APIs.
• 😀 The simplicity of using Google ID tokens and session cookies allows for a streamlined user authentication process across both the website and extension.
• 😀 The speaker invites feedback from the audience for potential improvements to the authentication process and mentions actively engaging with comments.

Q & A

What is the main authentication method used in this script?

The main authentication method used is Google authentication via an ID token. The ID token is sent to the server, verified using Google's Auth library, and then the user is authenticated.

What happens if the ID token is valid?

If the ID token is valid, the server extracts the user's information from it, such as their Google ID, email, and profile data, and stores it in the session cookie, keeping the user authenticated for future requests.

Why is the session cookie important in this authentication process?

The session cookie is important because it allows the user to remain authenticated across different requests without needing to verify the ID token each time. It contains the user ID, and the server can check it to confirm the user’s session.

What happens when a user logs in for the first time?

When a user logs in for the first time, the system checks if the Google ID exists in the database. If not, a new user is created with the Google ID and associated details.

How does the extension maintain synchronization with the website?

The extension automatically uses the same session cookie as the website, meaning when the user is authenticated on the website, the extension is also authenticated, and vice versa. This ensures both platforms stay synchronized.

How is the user logged out from both the website and the extension?

The user is logged out by calling the logout endpoint on the server, which invalidates the session cookie. Once the cookie is cleared, the user is logged out from both the website and the extension.

What is the role of the 'verifyGoogleIdToken' middleware?

The 'verifyGoogleIdToken' middleware is responsible for extracting the ID token from the request, verifying its validity using Google's Auth library, and then extracting user data from the token to store in the session.

What are the benefits of using the 'cookie-session' library?

The 'cookie-session' library simplifies session management by storing the user session data (like user ID) in an encrypted cookie. This allows the server to authenticate users without needing to check the ID token every time.

Can the server rely solely on the ID token for authentication?

No, while the ID token is used for initial authentication, the server relies on the session cookie to maintain the user's authentication state for future requests, ensuring a seamless experience.

What future considerations are mentioned regarding Google API access?

The script mentions that if access to Google APIs is needed in the future, the system may need to handle refresh and access tokens for ongoing API communication, though the current setup only uses the ID token for login purposes.