OAuth2 Mock Server

oauth2-mock-server is a JavaScript/TypeScript library designed to provide a configurable OAuth2/OpenID Connect server for automated testing and development purposes. It allows developers to simulate an OAuth2 provider to issue verifiable access tokens without needing a full-fledged identity provider, making it ideal for unit and integration tests. The library supports various OAuth2 grant types, including Client Credentials, Resource Owner Password Credentials, Authorization Code (with PKCE), and Refresh Token grants. It also supports multiple JWK formats for signing tokens (RSA, EC, EdDSA). The current stable version is 8.2.2, with recent releases indicating an active maintenance and development cadence focused on dependency updates, minor feature additions, and bug fixes. A key differentiator is its programmatic control via event emitters for customizing server behavior, allowing for specific test scenarios, such as modifying token expiration or adding custom claims. It is explicitly not intended for production use due to a lack of full feature parity and security hardening.