Seth Mathai

Gemfile

@@ -2,6 +2,15 @@ source 'https://rubygems.org'
 
 ruby File.read('.ruby-version').chomp
 
+gem 'httparty'
+gem 'sidekiq'
+gem 'whenever', require: false
+gem 'will_paginate'
+
+group :development, :test do
+  gem 'factory_bot_rails'
+end
+
 gem 'byebug', platforms: [:mri, :mingw, :x64_mingw], group: [:development, :test]
 gem 'capybara', group: [:development, :test]
 gem 'coffee-rails'

Gemfile.lock

@@ -69,6 +69,7 @@ GEM
     addressable (2.8.1)
       public_suffix (>= 2.0.2, < 6.0)
     bcrypt (3.1.18)
+    bigdecimal (3.1.8)
     bindex (0.8.1)
     builder (3.2.4)
     byebug (11.1.3)
@@ -82,6 +83,7 @@ GEM
       regexp_parser (>= 1.5, < 3.0)
       xpath (~> 3.2)
     childprocess (4.1.0)
+    chronic (0.10.2)
     coderay (1.1.3)
     coffee-rails (5.0.0)
       coffee-script (>= 2.2.0)
@@ -91,7 +93,9 @@ GEM
       execjs
     coffee-script-source (1.12.2)
     concurrent-ruby (1.1.10)
+    connection_pool (2.4.1)
     crass (1.0.6)
+    csv (3.3.0)
     devise (4.8.1)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
@@ -102,9 +106,18 @@ GEM
     digest (3.1.0)
     erubi (1.11.0)
     execjs (2.8.1)
+    factory_bot (6.4.6)
+      activesupport (>= 5.0.0)
+    factory_bot_rails (6.4.3)
+      factory_bot (~> 6.4)
+      railties (>= 5.0.0)
     ffi (1.15.5)
     globalid (1.0.0)
       activesupport (>= 5.0)
+    httparty (0.22.0)
+      csv
+      mini_mime (>= 1.0.0)
+      multi_xml (>= 0.5.2)
     i18n (1.12.0)
       concurrent-ruby (~> 1.0)
     jbuilder (2.11.5)
@@ -113,6 +126,7 @@ GEM
     listen (3.7.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
+    logger (1.6.0)
     loofah (2.19.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
@@ -124,6 +138,8 @@ GEM
     mini_mime (1.1.2)
     mini_portile2 (2.8.0)
     minitest (5.16.3)
+    multi_xml (0.7.1)
+      bigdecimal (~> 3.1)
     net-imap (0.2.3)
       digest
       net-protocol
@@ -186,6 +202,8 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
+    redis-client (0.22.2)
+      connection_pool
     regexp_parser (2.5.0)
     responders (3.0.1)
       actionpack (>= 5.0)
@@ -224,6 +242,12 @@ GEM
       rexml (~> 3.2, >= 3.2.5)
       rubyzip (>= 1.2.2, < 3.0)
       websocket (~> 1.0)
+    sidekiq (7.3.0)
+      concurrent-ruby (< 2)
+      connection_pool (>= 2.3.0)
+      logger
+      rack (>= 2.2.4)
+      redis-client (>= 0.22.2)
     spring (4.1.0)
     sprockets (4.1.1)
       concurrent-ruby (~> 1.0)
@@ -254,6 +278,9 @@ GEM
     websocket-driver (0.7.5)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
+    whenever (1.0.0)
+      chronic (>= 0.6.3)
+    will_paginate (4.0.1)
     xpath (3.2.0)
       nokogiri (~> 1.8)
     zeitwerk (2.6.0)
@@ -266,6 +293,8 @@ DEPENDENCIES
   capybara
   coffee-rails
   devise
+  factory_bot_rails
+  httparty
   jbuilder
   listen
   pg
@@ -275,11 +304,14 @@ DEPENDENCIES
   rspec-rails
   sass-rails
   selenium-webdriver
+  sidekiq
   spring
   turbolinks
   tzinfo-data
   uglifier
   web-console
+  whenever
+  will_paginate
 
 RUBY VERSION
    ruby 3.1.2p20

app/assets/stylesheets/application.css

@@ -13,3 +13,44 @@
  *= require_tree .
  *= require_self
  */
+table {
+  border-collapse: collapse;
+  width: 100%;
+}
+
+th,
+td {
+  border: 1px solid #ddd;
+  padding: 8px;
+  text-align: left;
+}
+
+th {
+  background-color: #f2f2f2;
+}
+
+.recommend-button {
+  padding: 5px 10px;
+  background-color: #007bff;
+  color: white;
+  border: none;
+  border-radius: 3px;
+  cursor: pointer;
+  width: 100%;
+}
+
+.story-link {
+  color: #2c3e50;
+  text-decoration: none;
+  font-weight: bold;
+  transition: color 0.3s ease;
+}
+
+.story-link:hover {
+  color: #3498db;
+  text-decoration: underline;
+}
+
+.story-link:visited {
+  color: #8e44ad;
+}

app/controllers/application_controller.rb

@@ -1,3 +1,9 @@
 class ApplicationController < ActionController::Base
   protect_from_forgery with: :exception
+
+  private
+
+  def page
+    params[:page] || 1
+  end
 end

app/controllers/hacker_news_recommendations_controller.rb

@@ -0,0 +1,23 @@
+class HackerNewsRecommendationsController < ApplicationController
+  before_action :authenticate_user!
+
+  def create
+    @recommendation = current_user.hacker_news_recommendations.new(hacker_news_story_id: params[:hacker_news_story_id])
+
+    if @recommendation.save
+      redirect_to root_path, notice: 'Story recommended successfully.'
+    else
+      redirect_to root_path, alert: 'Unable to recommend story.'
+    end
+  end
+
+  def destroy
+    @recommendation = current_user.hacker_news_recommendations.find(params[:id])
+
+    if @recommendation.destroy
+      redirect_to root_path, notice: 'Recommendation removed successfully.'
+    else
+      redirect_to root_path, alert: 'Unable to remove recommendation.'
+    end
+  end
+end

app/controllers/hacker_news_stories_controller.rb

@@ -0,0 +1,7 @@
+class HackerNewsStoriesController < ApplicationController
+  before_action :authenticate_user!
+
+  def index
+    @stories = HackerNewsStory.includes(:users, :hacker_news_recommendations).by_popularity.paginate(page: page, per_page: 50)
+  end
+end

app/models/hacker_news_client.rb

@@ -0,0 +1,14 @@
+require 'httparty'
+
+class HackerNewsClient
+  include HTTParty
+  base_uri 'https://hacker-news.firebaseio.com/v0'
+
+  def top_story_ids
+    self.class.get('/topstories.json?print=pretty')
+  end
+
+  def fetch_item(id)
+    self.class.get("/item/#{id}.json?print=pretty")
+  end
+end

app/models/hacker_news_recommendation.rb

@@ -0,0 +1,6 @@
+class HackerNewsRecommendation < ApplicationRecord
+  belongs_to :user
+  belongs_to :hacker_news_story, counter_cache: :recommendations_count
+
+  validates :user_id, uniqueness: { scope: :hacker_news_story_id }
+end

app/models/hacker_news_story.rb

@@ -0,0 +1,12 @@
+class HackerNewsStory < ApplicationRecord
+  has_many :hacker_news_recommendations, dependent: :destroy
+  has_many :users, through: :hacker_news_recommendations, counter_cache: true, source: :user
+
+  alias_attribute :recommended_by, :users
+  alias_attribute :recommendations, :hacker_news_recommendations
+
+  validates :hacker_news_id, presence: true, uniqueness: true
+  validates :author, :score, :hacker_news_timestamp, :title, :url, presence: true
+
+  scope :by_popularity, -> { order(recommendations_count: :desc, score: :desc) }
+end

app/models/user.rb

@@ -1,6 +1,15 @@
 class User < ApplicationRecord
+  has_many :hacker_news_recommendations, dependent: :destroy
+  has_many :hacker_news_stories, through: :hacker_news_recommendations
+
+  alias_attribute :recommended_stories, :hacker_news_stories
+
   # Include default devise modules. Others available are:
   # :confirmable, :lockable, :timeoutable and :omniauthable
   devise :database_authenticatable, :registerable,
          :recoverable, :rememberable, :trackable, :validatable
+
+  def full_name
+    "#{first_name} #{last_name}"
+  end
 end

app/services/hacker_news_story_recorder.rb

@@ -0,0 +1,30 @@
+class HackerNewsStoryRecorder
+  include ActiveModel::Model
+  REQUIRED_KEYS = %w[id by score time title url]
+
+  attr_accessor :api_response
+
+  validates :api_response, presence: true
+  validate :api_response_is_hacker_news_story
+
+  def execute
+    return false if invalid?
+
+    hacker_news_story_record = HackerNewsStory.find_or_initialize_by(hacker_news_id: api_response['id'])
+    hacker_news_story_record.update(
+      hacker_news_id: api_response['id'],
+      author: api_response['by'],
+      score: api_response['score'],
+      hacker_news_timestamp: api_response['time'],
+      title: api_response['title'],
+      url: api_response['url']
+    )
+  end
+
+  private
+
+  def api_response_is_hacker_news_story
+    return errors.add(:api_response, 'is not a HTTParty::Response') unless api_response.is_a?(HTTParty::Response)
+    return errors.add(:api_response, 'is missing required keys') unless REQUIRED_KEYS.all? { |key| api_response.key?(key) }
+  end
+end

app/sidekiq/fetch_hn_top_stories_job.rb

@@ -0,0 +1,12 @@
+class FetchHnTopStoriesJob
+  include Sidekiq::Job
+
+  def perform
+    client = HackerNewsClient.new
+    top_story_ids = client.top_story_ids
+    saved_story_ids = HackerNewsStory.pluck(:hacker_news_id)
+
+    ids_to_fetch = top_story_ids - saved_story_ids
+    ids_to_fetch.each { |id| RecordHnItemJob.perform_async(id) }
+  end
+end

app/sidekiq/record_hn_item_job.rb

@@ -0,0 +1,11 @@
+class RecordHnItemJob
+  include Sidekiq::Job
+
+  def perform(id)
+    client = HackerNewsClient.new
+    item = client.fetch_item(id)
+
+    recorder = HackerNewsStoryRecorder.new(api_response: item)
+    recorder.execute
+  end
+end

app/views/devise/sessions/new.html.erb

@@ -0,0 +1,24 @@
+<h2>Log in</h2>
+
+<%= form_for(resource, as: resource_name, url: session_path(resource_name)) do |f| %>
+  <div class="field">
+    <%= f.label :email %><br />
+    <%= f.email_field :email, autofocus: true, autocomplete: "email" %>
+  </div>
+
+  <div class="field">
+    <%= f.label :password %><br />
+    <%= f.password_field :password, autocomplete: "current-password" %>
+  </div>
+
+  <% if devise_mapping.rememberable? %>
+    <div class="field">
+      <%= f.check_box :remember_me %>
+      <%= f.label :remember_me %>
+    </div>
+  <% end %>
+
+  <div class="actions">
+    <%= f.submit "Log in" %>
+  </div>
+<% end %>

app/views/devise/shared/_error_messages.html.erb

@@ -0,0 +1,15 @@
+<% if resource.errors.any? %>
+  <div id="error_explanation">
+    <h2>
+      <%= I18n.t("errors.messages.not_saved",
+                 count: resource.errors.count,
+                 resource: resource.class.model_name.human.downcase)
+       %>
+    </h2>
+    <ul>
+      <% resource.errors.full_messages.each do |message| %>
+        <li><%= message %></li>
+      <% end %>
+    </ul>
+  </div>
+<% end %>