Ruby on rails 将rails任务转换为rake

我的模型/文件夹中当前有此文件：

class Show < ActiveRecord::Base
  require 'nokogiri'
  require 'open-uri'

  has_many :user_shows
  has_many :users, through: :user_shows

  def self.update_all_screenings
    Show.all.each do |show|
        show.update_attribute(:next_screening, Show.update_next_screening(show.url))
    end
  end

  def self.update_next_screening(url)
    nextep = Nokogiri::HTML(open(url))
    ## Finds the title of the show and extracts the date of the show and converts to string ##
    begin

        title = nextep.at_css('h1').text
        date = nextep.at_css('.next_episode .highlight_date').text[/\d{1,2}\/\d{1,2}\/\d{4}/]
        date = date.to_s

    ## Because if it airs today it won't have a date rather a time this checks whether or not 
    ## there is a date. If there is it will remain, if not it will insert todays date
    ## plus get the time that the show is airing    
        if date =~ /\d{1,2}\/\d{1,2}\/\d{4}/
            showtime = DateTime.strptime(date, "%m/%d/%Y")
        else
            date = DateTime.now.strftime("%D")
            time = nextep.at_css('.next_episode .highlight_date').text[/\dPM|\dAM/]
            time = time.to_s
            showtime = date + " " + time
            showtime = DateTime.strptime(showtime, "%m/%d/%y %l%p")

        end

        return showtime

    rescue
        return nil
    end
  end
end

这需要很长时间。我目前有一个非常类似的脚本，它是一个rake文件，必须执行两倍于刮取量的操作，并设法在大约10分钟内完成，而这一个操作将需要8个小时。所以我想知道如何将这个文件转换成rake任务？我正在构建的整个应用程序都取决于它能否在最多1小时内完成

下面是另一个脚本供参考：

require 'mechanize'

namespace :show  do

  desc "add tv shows from web into database"
  task :scrape => :environment do
    puts 'scraping...'

    Show.delete_all

agent = Mechanize.new
agent.get 'http://www.tv.com/shows/sort/a_z/'
agent.page.search('//div[@class="alphabet"]//li[not(contains(@class, "selected"))]/a').each do |letter_link|
  agent.get letter_link[:href]
  letter = letter_link.text.upcase
  agent.page.search('//li[@class="show"]/a').map do |show_link| 
    Show.create(title: show_link.text, url:'http://tv.com' + show_link[:href].to_s + 'episodes/')
  end
  while next_page_link = agent.page.at('//div[@class="_pagination"]//a[@class="next"]') do
    agent.get next_page_link[:href]
    agent.page.search('//li[@class="show"]/a').map do |show_link|
      Show.create(title: show_link.text, url:'http://tv.com' + show_link[:href].to_s + 'episodes/')
  end
  end
end

end
end

---

Rake不是什么灵丹妙药——它不会让你的代码运行得更快

您可以做的是更高效地运行代码。代码中的主要时间使用者是迭代调用

open（url）

。如果您可以同时读取所有URL，那么整个过程所需的时间应该是现在所需时间的一小部分

您可以使用gem（或其他gem）为您处理此问题

——危险！未经测试的代码--

我没有使用此gem的经验，但您的代码可能如下所示：

require 'nokogiri'
require 'open-uri'
require 'typhoeus'

class Show < ActiveRecord::Base


  has_many :user_shows
  has_many :users, through: :user_shows

  def self.update_all_screenings
    hydra = Typhoeus::Hydra.hydra
    Show.all.each do |show|
      request = Typhoeus::Request.new(show.url, followlocation: true)
      request.on_complete do |response|
        show.update_attribute(:next_screening, Show.update_next_screening(response.body))
      end
      hydra.queue(request)
    end
    hydra.run
  end

  def self.update_next_screening(body)
    nextep = Nokogiri::HTML(body)
    ## Finds the title of the show and extracts the date of the show and converts to string ##
    begin

        title = nextep.at_css('h1').text
        date = nextep.at_css('.next_episode .highlight_date').text[/\d{1,2}\/\d{1,2}\/\d{4}/]
        date = date.to_s

    ## Because if it airs today it won't have a date rather a time this checks whether or not 
    ## there is a date. If there is it will remain, if not it will insert todays date
    ## plus get the time that the show is airing    
        if date =~ /\d{1,2}\/\d{1,2}\/\d{4}/
            showtime = DateTime.strptime(date, "%m/%d/%Y")
        else
            date = DateTime.now.strftime("%D")
            time = nextep.at_css('.next_episode .highlight_date').text[/\dPM|\dAM/]
            time = time.to_s
            showtime = date + " " + time
            showtime = DateTime.strptime(showtime, "%m/%d/%y %l%p")

        end

        return showtime

    rescue
        return nil
    end
  end
end

需要“nokogiri”
需要“打开uri”
需要“伤寒症”
类Show

---

上面的操作应该收集一个队列中的所有请求，并同时运行它们，对任何响应执行操作。

尝试延迟的\u作业。它很容易实现，而且你的方法将在后台运行。嘿@SachinPrasad这会加快它的速度吗？还是在作业完成时只会延迟？它只会在后台运行该方法。延迟的作业将使该方法异步，因此你不必等待该方法完成。@SachinPrasad ah ok。我打算在安装时使用它。然而，我需要这个脚本每天在1小时内运行，完成延迟的任务能确保这一点吗？@HarryLucas我不知道仅仅将它转换为rake任务是否是加速它的方法。您可以在不同的地方输入时间输出，以确定哪个操作需要这么长的时间。感谢您为此投入的时间！我试了一下，但似乎每一行都在返回：

performed EASY url=response\u code=301

@HarryLucas-try

request=typhous:：request.new（show.url，followlocation:true）

（我已经更新了帖子-应该遵循重定向）

require 'nokogiri'
require 'open-uri'
require 'typhoeus'

class Show < ActiveRecord::Base


  has_many :user_shows
  has_many :users, through: :user_shows

  def self.update_all_screenings
    hydra = Typhoeus::Hydra.hydra
    Show.all.each do |show|
      request = Typhoeus::Request.new(show.url, followlocation: true)
      request.on_complete do |response|
        show.update_attribute(:next_screening, Show.update_next_screening(response.body))
      end
      hydra.queue(request)
    end
    hydra.run
  end

  def self.update_next_screening(body)
    nextep = Nokogiri::HTML(body)
    ## Finds the title of the show and extracts the date of the show and converts to string ##
    begin

        title = nextep.at_css('h1').text
        date = nextep.at_css('.next_episode .highlight_date').text[/\d{1,2}\/\d{1,2}\/\d{4}/]
        date = date.to_s

    ## Because if it airs today it won't have a date rather a time this checks whether or not 
    ## there is a date. If there is it will remain, if not it will insert todays date
    ## plus get the time that the show is airing    
        if date =~ /\d{1,2}\/\d{1,2}\/\d{4}/
            showtime = DateTime.strptime(date, "%m/%d/%Y")
        else
            date = DateTime.now.strftime("%D")
            time = nextep.at_css('.next_episode .highlight_date').text[/\dPM|\dAM/]
            time = time.to_s
            showtime = date + " " + time
            showtime = DateTime.strptime(showtime, "%m/%d/%y %l%p")

        end

        return showtime

    rescue
        return nil
    end
  end
end