找到在 Rails 上使用 redis 缓存的最佳方法

Posted 2023-02-23

【中文标题】找到在 Rails 上使用 redis 缓存的最佳方法

【英文标题】：Find a best way to work with redis cache on rails

【发布时间】：2019-09-08 17:18:37

【问题描述】：

我尝试使用 Redis 在 Rails 上进行缓存，但在尝试缓存多语言时遇到了挑战。因为我的Redis需要用table_translations缓存

我尝试了一些代码，但我认为这不是最好的方法

我有使用 Erb 模板的实例变量

def index
  @posts = fetch_posts
  @translations = fetch_translations

  puts @posts
  puts @translations
end

Redis 像这样抓取

private
  def fetch_posts
    begin
      posts = $redis.get "posts"

      if posts.nil?
        posts = []

        Post.all.order("id ASC").each do |post|
          posts << post
        end

        posts = posts.to_json

        $redis.set "posts", posts
      end

      posts = JSON.load posts
    rescue => error
      puts error.inspect
      posts = Post.all
    end
    posts
  end

  def fetch_translations
    begin
      translations = $redis.get "translations"

      if translations.nil?

        translations = []

        Post.all.order("id ASC").each do |post|
          post.translations.order("locale ASC").each do |translation|
            translations << translation
          end
        end

        translations = translations.to_json

        $redis.set "translations", translations
      end

      translations = JSON.load translations
    rescue => error
      puts error.inspect
      translations = Post.all
    end
    translations
  end

我这样做是因为我需要获取帖子的所有语言版本，所以我为翻译制作了一个 Redis 密钥

和我的输出：

"id":1,"slug":"hello-world","thumb_url":"thumbs/null","thumb_file_name":null,"thumb_content_type":null,"thumb_file_size":null,"thumb_updated_at":null,"featured":false,"hidden":false,"created_at":"2019-04-18T07:05:09.117Z","updated_at":"2019-04-18T07:27:55.830Z"
"title":"Xin chao","description":"Day la bai viet dau tien, duoc viet tu rails CMS","body":"xin chao cac ban"
"title":"Hello World","description":"This is first post from rails CMS","body":"Hello every body"

我找到了将输出变成密钥的最佳解决方案，如下所示：

"id":1,"slug":"hello-world","thumb_url":"thumbs/null","thumb_file_name":null,"thumb_content_type":null,"thumb_file_size":null,"thumb_updated_at":null,"featured":false,"hidden":false,"created_at":"2019-04-18T07:05:09.117Z","updated_at":"2019-04-18T07:27:55.830Z","title":"Xin chao","description":"Đay la bai viet đau tien, đuoc viet tu rails CMS","body":"xin chao cac ban"
"id":1,"slug":"hello-world","thumb_url":"thumbs/null","thumb_file_name":null,"thumb_content_type":null,"thumb_file_size":null,"thumb_updated_at":null,"featured":false,"hidden":false,"created_at":"2019-04-18T07:05:09.117Z","updated_at":"2019-04-18T07:27:55.830Z",title":"Hello World","description":"This is first post from rails CMS","body":"Hello every body"

我的代码可以正常工作，但我需要你的帮助才能让它变得更好，请帮助我提高我的技能

感谢您的帮助

【参考方案1】：

您可以使用内置的 Rails 缓存处理程序，这样您就不需要处理 .nil? 对缓存键的调用。

  private

  def fetch_posts
    posts = Rails.cache.fetch("posts") do
      begin
        Post.all.order("id ASC").as_json
      rescue => error
        puts error.inspect
        Post.all
      end
    end
    posts
  end

  def fetch_translations
    translations = Rails.cache.fetch("translations") do
      begin
        Post.all.order("id ASC").map do |post|
          post.translations.order("locale ASC").as_json
        end.flatten
      rescue => error
        puts error.inspect
        Post.all
      end
    end
    translations
  end

【讨论】：

谢谢你的东西@ErvalhouS :) 我会在其他情况下尝试 Rails 缓存

【参考方案2】：

我通过关注这个东西How do you add an array to another array in Ruby and not end up with a multi-dimensional result?找到了解决方案

概念是将两个数组中的所有属性展平，然后再次将其散列到新数组中

def fetch_posts
  posts = []

  Post.all.order("id ASC").each do |post|
    post.translations.each do |translation|
      posts << [*post.attributes.slice('slug','thumb_url'),*JSON.parse(translation.to_json)].to_h
    end
  end
end

希望对任何对我有同样问题的人有所帮助:)