Rails / SNSの人気順で記事を並び替えたい（カウント数を取得して保存） Facebook / Twitter / Pocket / はてな / Google+

module SnsCount

    require 'open-uri'
    require 'nokogiri'

    def pocket_count(url)
        api = "http://widgets.getpocket.com/v1/button?v=1&count=horizontal&url="
        content = get_content(api + url)
        return 0 if content.blank?

        content.xpath("//*[@id='cnt']").try(:text)
    end


    def twitter_count(url)
        api = "http://urls.api.twitter.com/1/urls/count.json?url="
        html = open(api + url).read
        return 0 if html.blank?

        json = JSON.parse(html)
        json["count"]
    end


    def hatena_count(url)
        api = "http://api.b.st-hatena.com/entry.count?url="
        html = open(api + url).read
        return 0 if html.blank?

        html
    end


    def facebook_count(url)
        api = "http://graph.facebook.com/"
        html = open(api + url).read
        return 0 if html.blank?

        json = JSON.parse(html)
        json["shares"]
    end


    def google_count(url)
        api = "https://apis.google.com/_/+1/fastbutton?url="
        content = get_content(api + url)
        return 0 if content.blank?

        content.xpath("//*[@id='aggregateCount']").try(:text)
    end


    def get_content(url)
        html = open(url).read
        Nokogiri::HTML(html, nil, 'utf-8')
    end

end

#Pocket
http://widgets.getpocket.com/v1/button?v=1&count=horizontal&url=

#Twitter
http://urls.api.twitter.com/1/urls/count.json?url=

#はてな
http://api.b.st-hatena.com/entry.count?url=

#Facebook
http://graph.facebook.com/

#Google+
https://apis.google.com/_/+1/fastbutton?url=

class PostsController < ApplicationController

    require 'sns_count'
    include SnsCount

    def show
      @post = Post.find(params[:id])
      @pocket = pocket_count("http://www.workabroad.jp/posts/#{post.id}")
    end

end

class AddSnsCountToPost < ActiveRecord::Migration
  def change
    add_column :posts, :pocket_count, :integer, default: 0
    add_column :posts, :twitter_count, :integer, default: 0
    add_column :posts, :hatena_count, :integer, default: 0
    add_column :posts, :facebook_count, :integer, default: 0
    add_column :posts, :google_count, :integer, default: 0
  end
end

namespace :sns do

    desc "Get SNS count and store them in DB."

    task get_sns_count: :environment do
        get_sns_count
    end

    def get_sns_count
        sns = SnsController.new

        Post.all.where(published: true).each do |post|
            # www(sub domain) is required.
            # Otherwise twitter/google/hatena won't return the count properly.
            base_url = "http://www.workabroad.jp/posts/"
            url = base_url + post.id.to_s
            puts "Getting SNS count: #{url}"
            post.pocket_count   = sns.pocket_count(url).to_i
            post.twitter_count  = sns.twitter_count(url).to_i
            post.hatena_count   = sns.hatena_count(url).to_i
            post.facebook_count = sns.facebook_count(url).to_i
            post.google_count   = sns.google_count(url).to_i

            puts    "p:#{post.pocket_count} | t:#{post.twitter_count} | h:#{post.hatena_count} | " +
                        "f:#{post.facebook_count} | g:#{post.google_count}"
            if post.changed?
                post.save
                puts "Saved!"
            else
                puts "Not Changed."
            end
            sleep(1)
        end
    end

end

class Post < ActiveRecord::Base

    scope :by_sns, -> { unscoped.order('pocket_count + twitter_count + hatena_count + facebook_count + google_count DESC') }

end

class PostsController < ApplicationController

    def index
      @popular_posts = Post.by_sns.limit(10)
    end

end