// {app_root}/config/plugin.js
exports.oAuth2Server = {
  enable: true,
  package: 'egg-oauth2-server',
};

// {app_root}/app/router.js
app.all('/user/token', app.oAuth2Server.token());
app.get('/user/authorize', app.oAuth2Server.authorize(), 'user.code');
app.get('/user/authenticate', app.oAuth2Server.authenticate(), 'user.authenticate');

// `ctx.state.oauth` has token or code data after middleware for controller.

// {app_root}/config/config.default.js
module.exports = config => {
  const exports = {};
  exports.oAuth2Server = {
    debug: config.env === 'local',
    grants: [ 'password' ],
  };
  return exports;
};

// {app_root}/app/extend/oauth.js
// or {app_root}/app/extend/oauth.ts
'use strict';

// need implement some follow functions
module.exports = app => {  
  class Model {
    constructor(ctx) {}
    async getClient(clientId, clientSecret) {}
    async getUser(username, password) {}
    async saveAuthorizationCode(code, client, user) {}
    async getAuthorizationCode(authorizationCode) {}
    async revokeAuthorizationCode(code) {}
    async saveToken(token, client, user) {}
    async getAccessToken(bearerToken) {}
    async revokeToken(token) {}
  }  
  return Model;
};