Passport Strategy Base Class

The `passport-strategy` package provides an abstract `Strategy` class that serves as the foundational interface for implementing concrete authentication strategies within the Passport.js ecosystem. It defines the core API, including the `authenticate()` method and helper functions like `success()`, `fail()`, `redirect()`, `pass()`, and `error()`, which custom strategies must implement or utilize to manage the authentication flow. While the core `passport` package is actively maintained (latest version ~0.7.0 as of late 2023), the `passport-strategy` package itself, version 1.0.0, has not seen updates since 2013, making it a very stable but effectively unmaintained base. Developers primarily interact with this module by extending its `Strategy` class to create custom authentication logic (e.g., `passport-local`, `passport-github`). Its key differentiator is its role as the common contract for all Passport strategies, enabling a highly modular and extensible authentication system for Node.js applications.