Add Endpoint for Viewing Lesson Completion Stats (TheOdinProject#967)

* Add Endpoint for Viewing Lesson Completion Stats

To keep an eye on lesson completion stats, we need access to lesson
completion data so we can make visulizations.

* Fix authentication, it wasn't checking both the username and password it was instead just checking the password. Also fixes some unit test formatting

* Allow endpoint to be queried with a date range

* Add additional configuration keys to env

* Stub out accessing mailchimp api in unit test

.env

@@ -0,0 +1,9 @@
+API_USERNAME: 'development'
+API_PASSWORD: 'qwerty123'
+GITHUB_API_TOKEN: 1234
+GITHUB_APP_ID: 1234
+GITHUB_SECRET: 1234
+GOOGLE_CLIENT_ID: 1234
+GOOGLE_CLIENT_SECRET: 1234
+MAILCHIMP_API_KEY: 1234
+MAILCHIMP_LIST_ID: 1234

.gitignore

@@ -45,7 +45,7 @@
 # Ignore application configuration
 /config/application.yml
 /config/database.yml
-.env
+.env.local
 
 # secret token
 .secret

Gemfile

@@ -44,7 +44,7 @@ group :development, :test do
   gem 'shoulda-matchers',                  '~> 3.1'
   gem 'rake',                              '~> 11.3'
   gem 'rails-controller-testing',          '~> 1.0'
-  gem 'figaro',                            '1.1'
+  gem 'dotenv-rails'
   gem 'bundle-audit'
 end
 

Gemfile.lock

@@ -102,6 +102,10 @@ GEM
       warden (~> 1.2.3)
     diff-lcs (1.3)
     docile (1.3.1)
+    dotenv (2.6.0)
+    dotenv-rails (2.6.0)
+      dotenv (= 2.6.0)
+      railties (>= 3.2, < 6.0)
     equalizer (0.0.11)
     erubi (1.7.1)
     erubis (2.7.0)
@@ -114,8 +118,6 @@ GEM
     faraday (0.12.2)
       multipart-post (>= 1.2, < 3)
     ffi (1.9.25)
-    figaro (1.1.0)
-      thor (~> 0.14)
     font-awesome-rails (4.7.0.4)
       railties (>= 3.2, < 6.0)
     friendly_id (5.2.4)
@@ -140,6 +142,7 @@ GEM
       concurrent-ruby (~> 1.0)
     ice_nine (0.11.2)
     jaro_winkler (1.5.1)
+    jaro_winkler (1.5.1-x86_64-darwin-17)
     jquery-rails (4.2.2)
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
@@ -365,6 +368,7 @@ GEM
 PLATFORMS
   ruby
   x86_64-darwin-15
+  x86_64-darwin-17
 
 DEPENDENCIES
   acts_as_votable
@@ -376,8 +380,8 @@ DEPENDENCIES
   database_cleaner (~> 1.5)
   derailed
   devise (~> 4.4.0)
+  dotenv-rails
   factory_bot_rails (~> 4.11)
-  figaro (= 1.1)
   font-awesome-rails (~> 4.7)
   friendly_id (~> 5.1)
   gibbon (~> 3.2.0)

app/controllers/api/lesson_completions_controller.rb

@@ -0,0 +1,36 @@
+module Api
+  class LessonCompletionsController < ApplicationController
+    before_action :authenticate
+
+    def index
+      render json: serialized_lesson_completions
+    end
+
+    private
+
+    def serialized_lesson_completions
+      Course.order(:position).map do |course|
+        CourseSerializer.as_json(course, between_dates)
+      end
+    end
+
+    def between_dates
+      (DateTime.parse(start_date)..DateTime.parse(end_date))
+    end
+
+    def start_date
+      params.fetch(:start_date, '2013/01/01')
+    end
+
+    def end_date
+      params.fetch(:end_date, DateTime.now.to_s)
+    end
+
+    def authenticate
+      authenticate_or_request_with_http_basic do |username, password|
+        username == ENV.fetch('API_USERNAME') &&
+          password == ENV.fetch('API_PASSWORD')
+      end
+    end
+  end
+end

app/serializers/course_serializer.rb

@@ -0,0 +1,27 @@
+class CourseSerializer
+  attr_reader :course, :between_dates
+  private :course, :between_dates
+
+  def initialize(course, between_dates = nil)
+    @course, @between_dates = course, between_dates
+  end
+
+  def self.as_json(course, between_dates = nil)
+    new(course, between_dates).as_json
+  end
+
+  def as_json(options = nil)
+    {
+      title: course.title,
+      sections: serialized_sections,
+    }
+  end
+
+  private
+
+  def serialized_sections
+    course.sections.map do |section|
+      SectionSerializer.as_json(section, between_dates)
+    end
+  end
+end

app/serializers/lesson_serializer.rb

@@ -0,0 +1,25 @@
+class LessonSerializer
+  attr_reader :lesson, :between_dates
+  private :lesson, :between_dates
+
+  def initialize(lesson, between_dates = nil)
+    @lesson, @between_dates = lesson, between_dates
+  end
+
+  def self.as_json(lesson, between_dates = nil)
+    new(lesson, between_dates).as_json
+  end
+
+  def as_json(options=nil)
+    {
+      title: lesson.title,
+      completions: completions.count,
+    }
+  end
+
+  private
+
+  def completions
+    lesson.lesson_completions.where(created_at: between_dates)
+  end
+end

app/serializers/section_serializer.rb

@@ -0,0 +1,27 @@
+class SectionSerializer
+  attr_reader :section, :between_dates
+  private :section, :between_dates
+
+  def initialize(section, between_dates = nil)
+    @section, @between_dates = section, between_dates
+  end
+
+  def self.as_json(section, between_dates = nil)
+    new(section, between_dates).as_json
+  end
+
+  def as_json(options=nil)
+    {
+      title: section.title,
+      lessons: serialized_lessons
+    }
+  end
+
+  private
+
+  def serialized_lessons
+    section.lessons.map do |lesson|
+      LessonSerializer.as_json(lesson, between_dates)
+    end
+  end
+end

app/services/mailchimp_subscription.rb

@@ -9,9 +9,7 @@ def initialize(options)
   end
 
   def self.create(options)
-    instance = new(options)
-    instance.create
-    instance
+    new(options).create
   end
 
   def create

config/routes.rb

@@ -14,6 +14,10 @@
     get '/confirm_email' => 'users#send_confirmation_link'
   end
 
+  namespace :api do
+    resources :lesson_completions, only: [:index]
+  end
+
   get 'home' => 'static_pages#home'
   get 'about' => 'static_pages#about'
   get 'faq' => 'static_pages#faq'

spec/controllers/api/lesson_completions_controller_spec.rb

@@ -0,0 +1,78 @@
+require 'rails_helper'
+
+module Api
+  RSpec.describe LessonCompletionsController do
+    let(:params) { { start_date: start_date, end_date: end_date } }
+    let(:start_date) { '2019/01/01' }
+    let(:end_date) { '2019/01/31' }
+    let!(:course) { create(:course, title: 'Web Development 101', position: 1) }
+    let(:serialized_course) do
+      {
+        'title' => 'Web Development 101',
+        'sections' => [
+          {
+            'title' => 'Installations',
+            'lessons' => [
+              'title' => 'Overview',
+              'completions' => 1,
+            ]
+          }
+        ]
+      }
+    end
+    let(:username) { 'development' }
+    let(:password) { 'qwerty123' }
+    let(:authenticate_request) do
+      request.env['HTTP_AUTHORIZATION'] = ActionController::HttpAuthentication::Basic.
+      encode_credentials(username, password)
+    end
+    let(:between_dates) do
+      (DateTime.parse(start_date)..DateTime.parse(end_date))
+    end
+
+    before do
+      allow(CourseSerializer).to receive(:as_json).with(course, between_dates).
+        and_return(serialized_course)
+    end
+
+    describe '#index' do
+      context 'when authenticated' do
+
+        before do
+          authenticate_request
+        end
+
+        it 'returns a 200 status code' do
+          get :index, params: params
+          expect(response.status).to eql(200)
+        end
+
+        it 'renders serialized courses in json format' do
+          get :index, params: params
+          expect(JSON.parse(response.body)).to eql([serialized_course])
+        end
+
+        context 'when start and end dates are not present' do
+          let(:params) { { } }
+          let(:between_dates) do
+            (DateTime.parse('2013/01/01')..DateTime.parse(DateTime.now.to_s))
+          end
+
+          it 'uses the default dates' do
+            get :index, params: params
+
+            expect(CourseSerializer).to have_received(:as_json).
+              with(course, between_dates)
+          end
+        end
+      end
+
+      context 'when not authenticated' do
+        it 'does not allow access' do
+          get :index, params: params
+          expect(response.status).to eql(401)
+        end
+      end
+    end
+  end
+end

spec/rails_helper.rb

@@ -79,5 +79,5 @@
 
   config.include(Shoulda::Matchers::ActiveModel, type: :model)
   config.include(Shoulda::Matchers::ActiveRecord, type: :model)
-  config.include(MailchimpHelper)
+  config.include FactoryBot::Syntax::Methods
 end

spec/serializers/course_serializer_spec.rb

@@ -0,0 +1,40 @@
+require 'rails_helper'
+
+RSpec.describe CourseSerializer do
+  subject { described_class.as_json(course, between_dates) }
+
+  let(:course) do
+    double(
+      'Section',
+      title: 'Web Development 101',
+      sections: sections,
+    )
+  end
+  let(:between_dates) do
+    (DateTime.parse('2019/01/01')..DateTime.parse('2019/12/31'))
+  end
+  let(:sections) { [section] }
+  let(:section) { double('Section') }
+  let(:serialized_section) do
+    {
+      title: 'Installations',
+      lessons: [{ title: 'Overview', completions: 1 }],
+    }
+  end
+
+  describe '#as_json' do
+    let(:serialized_course) do
+      {
+        title: 'Web Development 101',
+        sections: [serialized_section],
+      }
+    end
+
+    before do
+      allow(SectionSerializer).to receive(:as_json).
+        with(section, between_dates).and_return(serialized_section)
+    end
+
+    it { is_expected.to eql(serialized_course) }
+  end
+end

spec/serializers/lesson_serializer_spec.rb

@@ -0,0 +1,32 @@
+require 'rails_helper'
+
+RSpec.describe LessonSerializer do
+  subject { described_class.as_json(lesson, between_dates) }
+
+  let(:lesson) do
+    double('Lesson', title: 'Overview', lesson_completions: lesson_completions)
+  end
+  let(:between_dates) do
+    (DateTime.parse('2019/01/01')..DateTime.parse('2019/12/31'))
+  end
+  let(:lesson_completions) { [lesson_completion] }
+  let(:lesson_completion) do
+    double('LessonCompletion', created_at: '2019/01/10')
+  end
+
+  describe '#as_json' do
+    let(:serialized_lesson) do
+      {
+        title: 'Overview',
+        completions: 1
+      }
+    end
+
+    before do
+      allow(lesson_completions).to receive(:where).
+        with(created_at: between_dates).and_return([lesson_completion])
+    end
+
+    it { is_expected.to eql(serialized_lesson) }
+  end
+end