Merge pull request #35 from sad16/15-background-jobs

background jobs

Gemfile

@@ -51,6 +51,9 @@ gem 'pundit'
 gem 'doorkeeper'
 gem 'active_model_serializers', '~> 0.10'
 gem 'oj'
+gem 'sidekiq'
+gem 'whenever', require: false
+gem 'redis'
 
 group :development, :test do
   # Call 'byebug' anywhere in the code to stop execution and get a debugger console

Gemfile.lock

@@ -87,6 +87,7 @@ GEM
       activesupport
     childprocess (0.9.0)
       ffi (~> 1.0, >= 1.0.11)
+    chronic (0.10.2)
     cocoon (1.2.15)
     coderay (1.1.3)
     coffee-rails (4.2.2)
@@ -98,6 +99,7 @@ GEM
     coffee-script-source (1.12.2)
     commonjs (0.2.7)
     concurrent-ruby (1.1.5)
+    connection_pool (2.2.5)
     crass (1.0.4)
     devise (4.7.3)
       bcrypt (~> 3.0)
@@ -251,6 +253,7 @@ GEM
     rb-fsevent (0.10.3)
     rb-inotify (0.10.0)
       ffi (~> 1.0)
+    redis (4.4.0)
     regexp_parser (1.3.0)
     request_store (1.5.0)
       rack (>= 1.4)
@@ -293,6 +296,10 @@ GEM
       rubyzip (~> 1.2, >= 1.2.2)
     shoulda-matchers (4.0.1)
       activesupport (>= 4.2.0)
+    sidekiq (6.2.2)
+      connection_pool (>= 2.2.2)
+      rack (~> 2.0)
+      redis (>= 4.2.0)
     slim (4.0.1)
       temple (>= 0.7.6, < 0.9)
       tilt (>= 2.0.6, < 2.1)
@@ -345,6 +352,8 @@ GEM
     websocket-driver (0.7.0)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.3)
+    whenever (1.0.0)
+      chronic (>= 0.6.3)
     with_model (2.1.5)
       activerecord (>= 5.2)
     xpath (3.2.0)
@@ -381,10 +390,12 @@ DEPENDENCIES
   pundit
   rails (~> 5.2.2)
   rails-controller-testing
+  redis
   rspec-rails (~> 3.8)
   sass-rails (~> 5.0)
   selenium-webdriver
   shoulda-matchers
+  sidekiq
   slim-rails
   spring
   spring-watcher-listen (~> 2.0.0)
@@ -395,6 +406,7 @@ DEPENDENCIES
   validate_url
   web-console (>= 3.3.0)
   webdrivers (~> 4.0)
+  whenever
   with_model
 
 RUBY VERSION

app/assets/javascripts/notifications.js

@@ -0,0 +1,50 @@
+$(document).on('turbolinks:load', function() {
+  onAjaxSuccessSubscribeNotification($('.subscribe-notification-link'));
+  onAjaxSuccessUnsubscribeNotification($(`.unsubscribe-notification-link`));
+});
+
+function onAjaxSuccessSubscribeNotification(elem) {
+  $(elem)
+    .on('ajax:success', function(response) {
+      successSubscribeNotification(response, this);
+    })
+    .on('ajax:error', function(response) {
+      errorSubscribeNotification(response, this);
+    })
+}
+
+function successSubscribeNotification(response, elem) {
+  var notification = response.detail[0]['notification'];
+  var notificationBlock = $(elem).closest('.notification');
+  insertUnsubscribeNotificationLink(notification, notificationBlock);
+  onAjaxSuccessUnsubscribeNotification(notificationBlock.find('.unsubscribe-notification-link'));
+}
+
+function insertUnsubscribeNotificationLink(notification, notificationBlock) {
+  var unsubscribeNotificationLink = `<p><a class="unsubscribe-notification-link" rel="nofollow" data-method="delete" data-remote="true" href="/notifications/${notification.id}">Unsubscribe</a></p>`
+  notificationBlock.html(unsubscribeNotificationLink);
+}
+
+function onAjaxSuccessUnsubscribeNotification(elem) {
+  $(elem).on('ajax:success', function(response) {
+    successUnsubscribeNotification(response, this);
+  });
+}
+
+function successUnsubscribeNotification(response, elem) {
+  var notification = response.detail[0]['notification'];
+  var notificationBlock = $(elem).closest('.notification');
+  insertSubscribeNotificationLink(notification, notificationBlock);
+  onAjaxSuccessSubscribeNotification(notificationBlock.find('.subscribe-notification-link'));
+}
+
+function insertSubscribeNotificationLink(notification, notificationBlock) {
+  var subscribeNotificationLink = `<p><a class="subscribe-notification-link" rel="nofollow" data-method="post" data-remote="true" href="/questions/${notification.question_id}/notifications">Subscribe</a></p>`
+  notificationBlock.html(subscribeNotificationLink);
+}
+
+function errorSubscribeNotification(response, elem) {
+  var errors = response.detail[0]['errors'];
+  var notificationBlock = $(elem).closest('.notification');
+  notificationBlock.append(errors);
+}

app/controllers/notifications_controller.rb

@@ -0,0 +1,24 @@
+class NotificationsController < ApplicationController
+  before_action :authenticate_user!, only: [:create, :destroy]
+
+  def create
+    question = Question.find(params[:question_id])
+    notification = Notification.new(user: current_user, question: question)
+
+    if notification.save
+      render json: notification
+    else
+      render json: { errors: notification.errors.full_messages }, status: :unprocessable_entity
+    end
+  end
+
+  def destroy
+    notification = Notification.find(params[:id])
+
+    authorize notification
+
+    notification.destroy
+
+    render json: notification
+  end
+end

app/controllers/questions_controller.rb

@@ -13,6 +13,7 @@ def show
     @answer = @question.answers.new
     @answer.links.new
     @vote = current_user&.vote_by(@question) || @question.votes.new
+    @notification = Notification.find_by(user: current_user, question: @question)
     set_gon
   end
 

app/jobs/daily_digest_job.rb

@@ -0,0 +1,7 @@
+class DailyDigestJob < ApplicationJob
+  queue_as :default
+
+  def perform
+    Services::SendDailyDigest.new.call
+  end
+end

app/jobs/notifications_job.rb

@@ -0,0 +1,7 @@
+class NotificationsJob < ApplicationJob
+  queue_as :default
+
+  def perform(answer)
+    Services::SendNotifications.new.call(answer)
+  end
+end

app/mailers/daily_digest_mailer.rb

@@ -0,0 +1,6 @@
+class DailyDigestMailer < ApplicationMailer
+  def digest(user)
+    @questions_data = Services::DailyDigestData.new.call
+    mail to: user.email
+  end
+end

app/mailers/notification_mailer.rb

@@ -0,0 +1,6 @@
+class NotificationMailer < ApplicationMailer
+  def new_answer(user, answer)
+    @answer = answer
+    mail to: user.email
+  end
+end

app/models/answer.rb

@@ -17,6 +17,8 @@ class Answer < ApplicationRecord
 
   scope :bests, -> { where(question: Question.with_best_answer) }
 
+  after_create_commit :send_notification
+
   def mark_as_best
     question.update(best_answer_id: id)
   end
@@ -32,4 +34,10 @@ def assign_reward
   def unassign_reward
     reward&.unassign
   end
+
+  private
+
+  def send_notification
+    NotificationsJob.perform_later(self)
+  end
 end

app/models/notification.rb

@@ -0,0 +1,6 @@
+class Notification < ApplicationRecord
+  belongs_to :user
+  belongs_to :question
+
+  validates :user_id, uniqueness: { scope: [:question_id] }
+end

app/models/question.rb

@@ -9,6 +9,8 @@ class Question < ApplicationRecord
   has_one :reward, dependent: :destroy
 
   has_many :answers, dependent: :destroy
+  has_many :notifications, dependent: :destroy
+  has_many :subscribed_users, through: :notifications, source: :user
 
   has_many_attached :files
 
@@ -18,7 +20,15 @@ class Question < ApplicationRecord
 
   scope :with_best_answer, -> { where.not(best_answer_id: nil) }
 
+  after_create_commit :create_notification
+
   def answers_without_best
     answers.where.not(id: best_answer_id)
   end
+
+  private
+
+  def create_notification
+    notifications.create(user_id: user_id)
+  end
 end

app/models/user.rb

@@ -10,6 +10,7 @@ class User < ApplicationRecord
   has_many :votes, dependent: :destroy
   has_many :comments, dependent: :destroy
   has_many :authorizations, dependent: :destroy
+  has_many :notifications, dependent: :destroy
 
   def author_of?(resource)
     resource.user_id == id

app/policies/application_policy.rb

@@ -38,6 +38,8 @@ def author_of?(entity = record)
     user&.author_of?(entity)
   end
 
+  alias_method :owner_of?, :author_of?
+
   class Scope
     attr_reader :user, :scope
 

app/policies/notification_policy.rb

@@ -0,0 +1,5 @@
+class NotificationPolicy < ApplicationPolicy
+  def destroy?
+    owner_of?
+  end
+end

app/serializers/notification_serializer.rb

@@ -0,0 +1,3 @@
+class NotificationSerializer < ApplicationSerializer
+  attributes :id, :question_id, :user_id
+end

app/services/daily_digest_data.rb

@@ -0,0 +1,25 @@
+module Services
+  class DailyDigestData < ApplicationService
+    CACHE_KEY = 'daily_digest_data'.freeze
+
+    def call
+      Rails.cache.fetch(CACHE_KEY, expires_in: cache_expires_in) do
+        questions.map { |q| { id: q.id, title: q.title } }
+      end
+    end
+
+    private
+
+    def questions
+      Question.where('created_at >= ? AND created_at <= ?', yesterday.beginning_of_day, yesterday.end_of_day)
+    end
+
+    def yesterday
+      @yesterday ||= Date.yesterday
+    end
+
+    def cache_expires_in
+      Date.today.end_of_day
+    end
+  end
+end

app/services/send_daily_digest.rb

@@ -0,0 +1,19 @@
+module Services
+  class SendDailyDigest < ApplicationService
+    BATCH_SIZE = 500
+
+    def call
+      User.find_each(batch_size: BATCH_SIZE) { |u| deliver_mail(u) } if questions_data.present?
+    end
+
+    private
+
+    def deliver_mail(user)
+      DailyDigestMailer.digest(user).deliver_later
+    end
+
+    def questions_data
+      Services::DailyDigestData.new.call
+    end
+  end
+end

app/services/send_notifications.rb

@@ -0,0 +1,15 @@
+module Services
+  class SendNotifications < ApplicationService
+    BATCH_SIZE = 500
+
+    def call(answer)
+      answer.question.subscribed_users.find_each(batch_size: BATCH_SIZE) { |u| deliver_mail(u, answer) }
+    end
+
+    private
+
+    def deliver_mail(user, answer)
+      NotificationMailer.new_answer(user, answer).deliver_later
+    end
+  end
+end

app/views/daily_digest_mailer/digest.html.slim

@@ -0,0 +1,4 @@
+p Hi, it is daily digest!
+p Yesterday questions:
+- @questions_data.each do |q|
+  = link_to q[:title], question_url(id: q[:id])

app/views/notification_mailer/new_answer.html.slim

@@ -0,0 +1,5 @@
+p Hi
+p New answer by question:
+p = @answer.question.title
+p Answer
+p = @answer.body

app/views/questions/_question.html.slim

@@ -10,6 +10,12 @@
   .links
     = render "/shared/links/links_block", links: @question.links
 
+  .notification
+    - if @notification
+      p = link_to "Unsubscribe", notification_path(@notification), method: :delete, remote: true, class: "unsubscribe-notification-link"
+    - else
+      p = link_to "Subscribe", question_notifications_path(@question), method: :post, remote: true, class: "subscribe-notification-link"
+
   - if policy(@question).edit?
     p = link_to "Edit question", "#", class: "edit-question-link", data: {question_id: @question.id}
 

app/views/questions/index.html.slim

@@ -1,6 +1,6 @@
 h1 Questions
 
-- if policy(Question).new?
+- if user_signed_in?
   p = link_to "Ask question", new_question_path
 
 .questions-list

config/application.rb

@@ -26,5 +26,7 @@ class Application < Rails::Application
                        request_specs: false
 
     end
+
+    config.active_job.queue_adapter = :sidekiq
   end
 end

config/environments/development.rb

@@ -17,16 +17,15 @@
   if Rails.root.join('tmp', 'caching-dev.txt').exist?
     config.action_controller.perform_caching = true
 
-    config.cache_store = :memory_store
     config.public_file_server.headers = {
       'Cache-Control' => "public, max-age=#{2.days.to_i}"
     }
   else
     config.action_controller.perform_caching = false
-
-    config.cache_store = :null_store
   end
 
+  config.cache_store = :redis_cache_store, { url: 'redis://localhost:6379/1' }
+
   # Store uploaded files on the local file system (see config/storage.yml for options)
   config.active_storage.service = :amazon