如何在Rails中实现OpenID服务器？

gem 'openid_connect'

# config/initializers/openid_connect.rb
require 'openid_connect'

Rails.application.config.middleware.use OmniAuth::Builder do
  provider :openid_connect, {
    name: :my_openid,
    scope: [:openid, :profile, :email],
    response_type: :code,
    issuer: 'https://my-openid-provider.com',
    client_id: 'YOUR_CLIENT_ID',
    client_secret: 'YOUR_CLIENT_SECRET',
    redirect_uri: 'https://my-rails-app.com/auth/my_openid/callback',
  }
end

get '/auth/:provider/callback', to: 'sessions#create'

class SessionsController< ApplicationController
  def create
    # 从请求中获取身份验证信息
    auth_hash = request.env['omniauth.auth']

    # 使用身份验证信息创建或查找用户
    user = User.find_or_create_from_auth_hash(auth_hash)

    # 将用户登录
    session[:user_id] = user.id

    # 重定向到主页或其他目的地
    redirect_to root_path
  end
end

class User< ApplicationRecord
  def self.find_or_create_from_auth_hash(auth_hash)
    # 查找现有用户或创建新用户
    user = User.find_or_create_by(email: auth_hash.info.email) do |u|
      u.name = auth_hash.info.name
      u.image = auth_hash.info.image
    end

    # 更新用户信息（如果需要）
    user.name = auth_hash.info.name if user.name != auth_hash.info.name
    user.image = auth_hash.info.image if user.image != auth_hash.info.image

    # 保存更改并返回用户
    user.save!
    user
  end
end

<%= link_to 'Login with OpenID', '/auth/my_openid' %>