在Rails中“过滤”结果按类别

class ProductsController < ApplicationController
  before_action :authenticate_user, only: [:create, :update, :destroy]

  def index
    # ...
  end

  def create
    # ...
  end

  def update
    # ...
  end

  def destroy
    # ...
  end

  private

  def authenticate_user
    # 验证用户身份的逻辑
  end
end

class ProductsController < ApplicationController
  after_action :log_action, only: [:create, :update, :destroy]

  def index
    # ...
  end

  def create
    # ...
  end

  def update
    # ...
  end

  def destroy
    # ...
  end

  private

  def log_action
    # 记录日志的逻辑
  end
end

class ProductsController < ApplicationController
  around_action :measure_performance, only: [:index]

  def index
    # ...
  end

  private

  def measure_performance
    start_time = Time.now
    yield
    end_time = Time.now
    # 计算执行时间的逻辑
  end
end