Tony Lum Top News

Gemfile

@@ -20,3 +20,6 @@ gem 'turbolinks'
 gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
 gem 'uglifier'
 gem 'web-console', group: :development
+gem 'factory_bot_rails', group: [:development, :test]
+gem "webmock", group: [:development, :test]
+gem 'rails-controller-testing', group: [:development, :test]

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)
@@ -91,6 +92,9 @@ GEM
       execjs
     coffee-script-source (1.12.2)
     concurrent-ruby (1.1.10)
+    crack (1.0.0)
+      bigdecimal
+      rexml
     crass (1.0.6)
     devise (4.8.1)
       bcrypt (~> 3.0)
@@ -102,9 +106,15 @@ 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)
+    hashdiff (1.1.0)
     i18n (1.12.0)
       concurrent-ruby (~> 1.0)
     jbuilder (2.11.5)
@@ -170,6 +180,10 @@ GEM
       activesupport (= 7.0.4)
       bundler (>= 1.15.0)
       railties (= 7.0.4)
+    rails-controller-testing (1.0.5)
+      actionpack (>= 5.0.1.rc1)
+      actionview (>= 5.0.1.rc1)
+      activesupport (>= 5.0.1.rc1)
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
@@ -250,6 +264,10 @@ GEM
       activemodel (>= 6.0.0)
       bindex (>= 0.4.0)
       railties (>= 6.0.0)
+    webmock (3.23.1)
+      addressable (>= 2.8.0)
+      crack (>= 0.3.2)
+      hashdiff (>= 0.4.0, < 2.0.0)
     websocket (1.2.9)
     websocket-driver (0.7.5)
       websocket-extensions (>= 0.1.0)
@@ -266,12 +284,14 @@ DEPENDENCIES
   capybara
   coffee-rails
   devise
+  factory_bot_rails
   jbuilder
   listen
   pg
   pry-rails
   puma
   rails (~> 7.0.3)
+  rails-controller-testing
   rspec-rails
   sass-rails
   selenium-webdriver
@@ -280,6 +300,7 @@ DEPENDENCIES
   tzinfo-data
   uglifier
   web-console
+  webmock
 
 RUBY VERSION
    ruby 3.1.2p20

app/assets/stylesheets/application.css

@@ -13,3 +13,57 @@
  *= require_tree .
  *= require_self
  */
+
+ #main_component {
+    width: 65%;
+    margin: 0 auto;
+    background-color: #f6f6ef;
+    padding-left: 1em;
+    max-width: 1000px;
+ }
+
+ #login_buttons {
+    float: right;
+    margin: 5 auto;
+    padding: 1em;
+ }
+
+ .button {
+    width: 6em;
+    margin-bottom: .25em;
+ }
+
+ #title {
+    font-size: 3em;
+    color: #ff6600;
+ }
+ #header {
+    padding-bottom: 1em;
+    padding-top: 1em;
+ }
+
+ .story_box {
+    color: grey;
+    padding-bottom: .5em;
+ }
+
+ .arrow {
+    padding-right: .25em;
+    text-decoration: none;
+    color: grey
+ }
+
+ .title_line {
+    text-decoration: none;
+    font-weight: bold;
+    color: black
+ }
+
+ .counter {
+    padding-left: .3em;
+    padding-right: .45em;
+ }
+
+ .favorited {
+   color: orangered !important;
+ }

app/controllers/favorites_controller.rb

@@ -0,0 +1,20 @@
+class FavoritesController < ApplicationController
+    before_action :restrict_access
+
+    def create
+        Favorite.find_or_create_by!(story_id: params[:story_id], user_id: current_user.id)
+        redirect_back(fallback_location: root_path)
+    end
+
+    def destroy
+        Favorite.find_by(story_id: params[:story_id], user_id: current_user&.id)&.destroy
+        redirect_back(fallback_location: root_path)
+    end
+
+    private
+
+    def restrict_access
+        redirect_to new_user_session_path unless current_user
+    end
+end
+

app/controllers/pages_controller.rb

@@ -1,2 +1,13 @@
 class PagesController < ApplicationController
+    def home
+        @logged_in = current_user.present?
+        @stories_data = StoryService.get_stories_data(current_user)
+    end
+
+    def interesting_stories
+        @logged_in = current_user.present?
+        @stories_data = StoryService.get_interesting_stories(current_user)
+        render :home
+    end
 end
+

app/models/favorite.rb

@@ -0,0 +1,6 @@
+class Favorite < ApplicationRecord
+    belongs_to :user
+    belongs_to :story
+
+    validates :user_id, :story_id, presence: true
+end

app/models/story.rb

@@ -0,0 +1,7 @@
+class Story < ApplicationRecord
+    has_many :favorites, dependent: :destroy
+    has_many :users, through: :favorites
+
+    validates :external_story_id, :title, :url, :by, :time, presence: true
+
+end

app/models/user.rb

@@ -3,4 +3,17 @@ class User < ApplicationRecord
   # :confirmable, :lockable, :timeoutable and :omniauthable
   devise :database_authenticatable, :registerable,
          :recoverable, :rememberable, :trackable, :validatable
+
+  has_many :favorites, dependent: :destroy
+  has_many :stories, through: :favorites
+
+  before_create :placeholder_first_name
+
+  private
+
+  def placeholder_first_name
+    unless first_name
+      self.first_name = email.split("@").first
+    end
+  end
 end

app/services/hacker_news_api.rb

@@ -0,0 +1,70 @@
+class HackerNewsApi
+    BASE_URL = 'https://hacker-news.firebaseio.com'
+    RETRY_LIMIT = 3
+
+    class ApiInternalServiceError < StandardError; end
+
+    attr_accessor :retry_count
+
+    def initialize
+        @retry_count = RETRY_LIMIT
+    end
+
+    def self.get_current_stories_ids
+        new.get_current_stories_ids
+    end
+
+    def self.get_story_details(story_id)
+        new.get_story_details(story_id)
+    end
+
+    def get_current_stories_ids
+        default_return = []
+        uri = URI("#{BASE_URL}/v0/topstories.json")
+        api_request(uri, default_return)
+    end
+
+    # Return an object with story data
+    def get_story_details(story_id)
+        default_return = {}
+        return default_return if story_id.blank?
+
+        uri = URI("#{BASE_URL}/v0/item/#{story_id}.json")
+        api_request(uri, default_return)
+    end
+
+    private
+
+    def api_request(uri, default_return)
+        response = response(uri)
+        handle_response(response) || default_return
+    rescue
+        if @retry_count > 0
+            Rails.logger.info("Retrying request to #{uri}.")
+            @retry_count -= 1
+            retry 
+        else
+            Rails.logger.error("Exceeded maximum retries. API request failed with code #{response.code}")
+            default_return
+        end
+    end
+
+    def response(uri)
+        http = Net::HTTP.new(uri.host, uri.port)
+        http.use_ssl = true
+        headers = {'Accept': 'application/json'}
+        request = Net::HTTP::Get.new(uri.request_uri, headers)
+        http.request(request)
+    end
+
+    def handle_response(response)
+        case response.code.to_i
+        when 200..299
+            JSON.parse(response.body)
+        when 400..499
+            Rails.logger.error("API request failed with code #{response.code}. Bad Request Error, please check request.")
+        when 500..599
+            raise ApiInternalServiceError
+        end
+    end
+end

app/services/story_service.rb

@@ -0,0 +1,104 @@
+class StoryService
+    DEFAULT_NUMBER_OF_STORIES = 15
+
+    attr_reader :user
+
+    def initialize(user = nil)
+        @user = user
+    end
+
+    def self.get_stories_data(user)
+        new(user).get_stories_data
+    end
+
+    def self.get_interesting_stories(user)
+        new(user).get_interesting_stories
+    end
+
+    def get_stories_data
+        # Fetch ids of current stories from api
+        external_stories_ids = get_stories_ids_from_api
+        process_external_story_id_data(external_stories_ids).compact
+    end
+
+    def get_interesting_stories
+        external_stories_ids = Story.joins(:favorites).distinct.pluck(:external_story_id)
+        process_external_story_id_data(external_stories_ids).compact
+    end
+
+    private
+
+    def process_external_story_id_data(external_stories_ids)
+        external_stories_ids.first(DEFAULT_NUMBER_OF_STORIES).map do |external_story_id| 
+            story = find_or_fetch_story(external_story_id)
+            next unless story
+
+            generate_story_data_hash(story)
+        end
+    end
+
+    def generate_story_data_hash(story)
+        {
+            story: story,
+            favorite: get_favorite_user_string(story),
+            count: story_favorite_by_users(story).count,
+            favorite_by_user: favorite_by_user?(story)
+        }
+    end
+
+    def get_favorite_user_string(story)
+        usernames = story_favorite_by_users(story)
+        generate_favorite_user_string(usernames)
+    end
+
+    # Return a story object or nil if story is not found and api request fail
+    def find_or_fetch_story(external_story_id)
+        Story.includes(:users).find_by(external_story_id: external_story_id) || 
+        fetch_and_create_story(external_story_id) || 
+        nil
+    end
+
+    # Call api to get story data and create story if successful
+    def fetch_and_create_story(external_story_id)
+        fetched_story_data = get_story_data_from_api(external_story_id)
+        return nil unless fetched_story_data
+
+        create_story(fetched_story_data)
+    end
+
+    def create_story(data)
+        story = Story.new
+        story.external_story_id = data['id']
+        story.title = data['title']
+        story.by = data['by']
+        story.url = data['url']
+        story.time = Time.at(data['time'])
+        story.save!
+        story
+    rescue
+        nil
+    end
+
+    def generate_favorite_user_string(usernames)
+        count = usernames.count
+        output = usernames.first(3)
+        output << "and #{count - 3} more" if count > 3
+        output.join(", ")
+    end
+
+    def story_favorite_by_users(story)
+        story.users.pluck(:first_name)
+    end
+
+    def favorite_by_user?(story)
+        story.users.find_by(id: @user&.id).present?
+    end
+
+    def get_stories_ids_from_api
+        HackerNewsApi.get_current_stories_ids
+    end
+
+    def get_story_data_from_api(external_story_id)
+        HackerNewsApi.get_story_details(external_story_id)
+    end
+end