defmodule Boruta do
  @moduledoc """
  Boruta is the core of an OAuth provider giving business logic of authentication and authorization.

  It is intended to follow RFCs :
  - [RFC 6749 - The OAuth 2.0 Authorization Framework](https://tools.ietf.org/html/rfc6749)
  - [RFC 7662 - OAuth 2.0 Token Introspection](https://tools.ietf.org/html/rfc7662)

  As it, it helps implement a provider for authorization code, implicit, client credentials and resource owner password credentials grants. Then it follows Introspection to check tokens.

  Note : Refresh tokens are not implemented yet

  ## Installation
  1. __Schemas migration__

  Boruta need a migration for its schemas and persist both tokens and clients. This can be done by running
  ```
  mix boruta.gen.migration --with-accounts
  ```

  2. __Configuration__

  Boruta provides several configuration options, to customize them you can add configurations in `config.exs` as following
  ```
  config :boruta, Boruta.Oauth,
    repo: MyApp.Repo,
    expires_in: %{
      access_token: 24 * 3600,
      authorization_code: 60
    },
    token_generator: Boruta.TokenGenerator,
    secret_key_base: System.get_env("SECRET_KEY_BASE"),
    resource_owner: %{
      schema: Boruta.Accounts.User,
      checkpw_method: &Boruta.Accounts.HashSalt.checkpw/2
    }
  ```

  ## Integration
  This implementation follows a pseudo hexagonal architecture to invert dependencies to Application layer.
  In order to expose endpoints of an OAuth server with Boruta, you need implement the behaviour `Boruta.Oauth.Application` with all needed callbacks for `token/2`, `authorize/2` and `introspect/2` calls from `Boruta.Oauth`.

  This library has specific interfaces to interact with `Plug.Conn` requests.

  ## Feedback
  It is a work in progress, all feedbacks / feature requests / improvments are welcome -> [me](mailto:pascal.knoth@gmx.com)
  """
end