OAuth 2.0 Authentication

OAuth 2.0 is an industry-standard protocol for authorization, allowing third parties to gain limited access to HTTP services on behalf of a resource owner.

It provides a mechanism for clients to access resources belonging to another account without needing to reveal credentials. This guide covers all aspects of OAuth 2.0, including various grant types, security considerations, and practical implementation.

Token Scope: Limiting Access Rights (e.g., read, write, admin)

OAuth 2.0 Grant Types outline the different methods for obtaining access tokens.

The Authorization Code Grant is a common flow used when there's a user involved, allowing them to authorize access to their resources.

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PKCE Implementation (React SPA)

OpenID Connect (OIDC) extends OAuth 2.0 by adding authentication (verifying the identity of the user).

OpenID Connect provides authentication, while OAuth 2.0 primarily focuses on authorization. OIDC adds an ID token containing information about the user and standardized endpoints for retrieving user profile data.

Frequently asked questions

What is OAuth 2.0?

OAuth 2.0 is a protocol authorization that enables third parties to access HTTP services on behalf of a resource owner, without needing to reveal credentials.

How does the Authorization Code Grant work?

The Authorization Code Grant flow involves a client application requesting authorization from a user. Once authorized, the user receives an authorization code which the client exchanges for an access token.

What is the difference between Client Credentials and Authorization Code Grant?

Client Credentials are used for machine-to-machine communication where there's no user involved, like API-to-API interactions. The Authorization Code Grant is specifically designed for interactive applications with a user who needs to authorize access to their resources.

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