Merge pull request #171 from hpi-swt2/feature/two-sided-contacts

Two sided contacts

Gemfile

@@ -36,6 +36,7 @@ gem 'devise-bootstrap-views', '~> 1.1' # https://github.com/hisea/devise-bootstr
 gem 'activestorage-validator'
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
 gem 'tzinfo-data', platforms: %i[mingw mswin x64_mingw jruby] # https://github.com/tzinfo/tzinfo-data
+gem 'composite_primary_keys'
 
 #
 # Packaged JS, CSS libraries and helpers

Gemfile.lock

@@ -92,6 +92,8 @@ GEM
       xpath (~> 3.2)
     childprocess (3.0.0)
     coderay (1.1.3)
+    composite_primary_keys (12.0.6)
+      activerecord (~> 6.0.0)
     concurrent-ruby (1.1.7)
     crass (1.0.6)
     debug_inspector (1.0.0)
@@ -305,6 +307,7 @@ DEPENDENCIES
   bootstrap (~> 4.5, >= 4.5.2)
   byebug
   capybara (~> 3.33)
+  composite_primary_keys
   devise (~> 4.7, >= 4.7.3)
   devise-bootstrap-views (~> 1.1)
   devise-i18n (~> 1.9, >= 1.9.2)

app/controllers/contact_requests_controller.rb

@@ -1,5 +1,6 @@
 class ContactRequestsController < ApplicationController
   before_action :authenticate_user!
+  before_action :find_user, only: [:accept]
 
   def create
     requested_user = User.find(params[:user_id])
@@ -18,10 +19,12 @@ def destroy
   end
 
   def accept
-    user = User.find(params[:id])
-    user.contacts << current_user
-    user.save
-    current_user.contact_requests.delete(params[:id])
+    @user.contacts << current_user
+    current_user.contact_requests.delete(@user)
     redirect_to user_contact_requests_path(current_user), notice: t('user.contact_request.approved')
   end
+
+  def find_user
+    @user = User.find(params[:id])
+  end
 end

app/controllers/users_controller.rb

@@ -37,13 +37,6 @@ def index
     end
   end
 
-  def add_contact
-    authenticate_user!
-    current_user.contacts << User.find(params[:id])
-    current_user.save
-    redirect_to root_path
-  end
-
   def search
     @users = User.search(params[:search]).where.not(id: current_user.id)
     @users_to_add = @users.reject do |user|

app/models/friendship.rb

@@ -0,0 +1,19 @@
+# A class for handling contacts which ensures that the association is always symmetrical
+class Friendship < ApplicationRecord
+  self.table_name = 'users_users'
+  self.primary_keys = :user_id, :contact_id
+
+  belongs_to :user, inverse_of: :friendships
+  belongs_to :contact, class_name: 'User', inverse_of: :friendships
+
+  after_create do |c|
+    unless Friendship.find_by(user_id: c.contact_id, contact_id: c.user_id)
+      Friendship.create(user_id: c.contact_id, contact_id: c.user_id)
+    end
+  end
+
+  after_destroy do |c|
+    reciprocal = Friendship.find_by(contact_id: c.user_id, user_id: c.contact_id)
+    reciprocal&.destroy
+  end
+end

app/models/user.rb

@@ -15,14 +15,12 @@ class User < ApplicationRecord
   has_many :activities, dependent: :delete_all
   has_many :call_participants, dependent: :delete_all, inverse_of: :user
   has_many :jitsi_calls, through: :call_participants
+  has_many :friendships, dependent: :destroy, inverse_of: :user
+  has_many :contacts, through: :friendships
 
   # as we do not need to work with the relationship models as independent entities, `has_and_belongs_to_many` is fine
   # https://guides.rubyonrails.org/association_basics.html#choosing-between-has-many-through-and-has-and-belongs-to-many
   # rubocop:disable Rails/HasAndBelongsToMany
-  has_and_belongs_to_many :contacts,
-                          class_name: 'User',
-                          association_foreign_key: 'contact_id'
-
   has_and_belongs_to_many :contact_requests,
                           class_name: 'User',
                           join_table: 'users_contact_requests',

spec/features/user_add_contact_spec.rb

@@ -18,6 +18,7 @@
     click_button('✓')
     expect(page).not_to have_text(requested_user.email)
     expect(requesting_user.contacts).to include(requested_user)
+    expect(requested_user.contacts).to include(requesting_user)
   end
 
   it 'is possible to deny a contact request' do

spec/models/friendship_spec.rb

@@ -0,0 +1,33 @@
+require 'rails_helper'
+
+RSpec.describe Friendship, type: :model do
+  let(:users) { FactoryBot.create_list :user, 3 }
+
+  before { described_class.create(user_id: users[0].id, contact_id: users[1].id) }
+
+  it 'creates a symmetrical association' do
+    expect(described_class.find_by(user_id: users[0].id, contact_id: users[1].id)).to be_present
+    expect(described_class.find_by(user_id: users[1].id, contact_id: users[0].id)).to be_present
+  end
+
+  it 'deletes both parts of the association' do
+    described_class.find_by(user_id: users[0].id, contact_id: users[1].id).destroy!
+    expect(described_class.find_by(user_id: users[0].id, contact_id: users[1].id)).to be_blank
+    expect(described_class.find_by(user_id: users[1].id, contact_id: users[0].id)).to be_blank
+  end
+
+  describe 'multiple contacts' do
+    before { described_class.create(user_id: users[0].id, contact_id: users[2].id) }
+
+    it 'allows a user to have multiple contacts' do
+      expect(described_class.find_by(user_id: users[0].id, contact_id: users[1].id)).to be_present
+      expect(described_class.find_by(user_id: users[0].id, contact_id: users[2].id)).to be_present
+    end
+
+    it 'allows to only delete one of the contacts' do
+      described_class.find_by(user_id: users[0].id, contact_id: users[1].id).destroy!
+      expect(described_class.find_by(user_id: users[0].id, contact_id: users[1].id)).to be_blank
+      expect(described_class.find_by(user_id: users[0].id, contact_id: users[2].id)).to be_present
+    end
+  end
+end

spec/models/user_spec.rb

@@ -164,7 +164,30 @@
     end
 
     it 'destroys all participants when destroyed' do
-      expect { user.destroy }.to change(CallParticipant, :count).from(jitsi_calls.size).to(0)
+      expect { user.destroy }.to change(CallParticipant, :count).by(-jitsi_calls.size)
+    end
+  end
+
+  context 'with contacts' do
+    let(:contacts) { FactoryBot.create_list :user, 2 }
+
+    before do
+      user.save
+      contacts.each { |contact| user.friendships.create(contact: contact) }
+    end
+
+    it 'has associated contacts' do
+      expect(user.contacts).to include(*contacts)
+    end
+
+    it 'has friendships' do
+      expect(user.friendships.map(&:contact_id)).to include(*contacts.map(&:id))
+    end
+
+    it 'destroys all friendships when destroyed' do
+      user.destroy
+      expect(Friendship.where(user_id: user.id)).to be_empty
+      expect(Friendship.where(contact_id: user.id)).to be_empty
     end
   end
 end