05-07-project_delete.md

Unit 5

Chapter 7: Deleting Projects

In this chapter, you will provide the ability to delete projects. Only the owner of this object, a regular admin, or a super admin may have this ability.

New Branch

Enter the command "git checkout -b 05-07-project_delete".

Part A: Controller Level

Controller Test

• Edit the file test/controllers/projects_controller_test.rb. Add the following code immediately before the end of the definitions section:

  def delete_project
    delete project_path(@p2)
  end

  def delete_project_disabled
    assert_no_difference 'Project.count' do
      delete_project
      assert_redirected_to root_path
    end
  end

• Edit the file test/controllers/projects_controller_test.rb. Add the following code immediately before the last "end" statement:

  test 'should redirect delete when not logged in' do
    delete_project_disabled
  end

  test 'should redirect delete when logged in as the wrong user' do
    sign_in @u1, scope: :user
    delete_project_disabled
  end

  test 'should not redirect delete when logged in as the right user' do
    sign_in @u3, scope: :user
    assert_difference 'Project.count', -1 do
      delete_project
      assert_redirected_to user_path(@u3)
    end
  end

  test 'should not redirect delete when logged in as a regular admin' do
    sign_in @a4, scope: :admin
    assert_difference 'Project.count', -1 do
      delete_project
      assert_redirected_to user_path(@u3)
    end
  end

  test 'should not redirect delete when logged in as a super admin' do
    sign_in @a1, scope: :admin
    assert_difference 'Project.count', -1 do
      delete_project
      assert_redirected_to user_path(@u3)
    end
  end

• In the file test/controllers/projects_controller_test.rb, add the following line immediately before "class ProjectsControllerTest < ActionDispatch::IntegrationTest":

# rubocop:disable Metrics/ClassLength

• In the file test/controllers/projects_controller_test.rb, add the following line immediately after the last "end" statement:

# rubocop:enable Metrics/ClassLength

• Enter the command "sh testc.sh". All 5 new controller tests fail because of a missing route.

Routing

• In the file config/routes.rb, replace the line containing "resources :projects" with the following:

  resources :projects, only: [:show, :index, :create, :new, :update, :edit, :destroy] do

• Enter the command "sh testc.sh". All 5 new controller tests fail because the destroy action is not defined in the project controller.

Project Controller

• Edit the file app/controllers/projects_controller.rb. Add the following line just before the end of the before_action section:

  before_action :may_destroy_project, only: [:destroy]

• Just before the end of the action section in app/controllers/projects_controller.rb, add the following code:

  def destroy
    uid = Project.find(params[:id]).user_id
    Project.find(params[:id]).destroy
    flash[:success] = 'Project deleted'
    redirect_to user_path(uid)
  end

• Just before the definition of project_params, add the following code:

  def correct_user
    return false unless user_signed_in?
    current_user.id == Project.find(params[:id]).user_id
  end
  helper_method :correct_user

  def may_destroy_project
    return redirect_to(root_path) unless correct_user || admin_signed_in?
  end
  helper_method :may_destroy_project

• Enter the command "sh testc.sh". All tests should now pass.
• Enter the command "sh git_check.sh". All tests should pass, and there should be no offenses.
• Enter the following commands:

git add .
git commit -m "Added project delete (controller level)"

Part B: View Level

Integration Test

• Enter the command "rails generate integration_test project_delete".
• In the file test/integration/project_delete_test.rb, replace everything between "class ProjectDeleteTest < ActionDispatch::IntegrationTest" and the last "end" statement with the following:

  def no_delete_button
    visit project_path(@p2)
    assert page.has_no_link?('Delete Project', href: project_path(@p2))
  end

  def gets_delete_button
    visit project_path(@p2)
    assert page.has_link?('Delete Project', href: project_path(@p2))
  end

  def can_delete
    gets_delete_button
    assert_difference 'Project.count', -1 do
      click_on 'Delete Project'
    end
    assert_text 'Project deleted'
    assert page.has_css?('title', text: full_title('User: Roger Moore'),
                                  visible: false)
    assert page.has_css?('h1', text: 'User: Roger Moore',
                               visible: false)
  end

  test 'visitor does not get the delete button' do
    no_delete_button
  end

  test 'wrong user does not get the delete button' do
    login_as(@u1, scope: :user)
    no_delete_button
  end

  test 'right user gets the delete button' do
    login_as(@u3, scope: :user)
    gets_delete_button
  end

  test 'regular admin gets the delete button' do
    login_as(@a4, scope: :admin)
    gets_delete_button
  end

  test 'super admin gets the delete button' do
    login_as(@a1, scope: :admin)
    gets_delete_button
  end

  test 'right user can delete project' do
    login_as(@u3, scope: :user)
    can_delete
  end

  test 'regular admin can delete project' do
    login_as(@a4, scope: :admin)
    can_delete
  end

  test 'super admin can delete project' do
    login_as(@a1, scope: :admin)
    can_delete
  end

• Enter the command "sh test_app.sh". The last 6 of your new integration tests fail.
• Enter the command "alias test1='command for running failed tests minus the TESTOPTS portion'".
• Enter the command "test1". The same 6 tests fail because the delete button is missing.

Adding the Delete Button

• Edit the file app/views/projects/show.html.erb. Immediately after the edit button, add the following code:

<% # BEGIN: delete project button %>
<% @correct_user = false %>
<% if user_signed_in? %>
  <% @correct_user = true if current_user.id == Project.find(params[:id]).user_id %>
<% end %>
<% if @correct_user || admin_signed_in? %>
  <%= link_to "Delete Project", @project, method: :delete,
                                         data: { confirm: "Are you sure you wish to delete this project?" },
                                         class: "btn btn-danger"
  %>
  <br><br>
<% end %>
<% # END: delete project button %>

• Enter the command "test1". All tests should pass.
• Enter the command "sh git_check.sh". All tests should pass, but Rails Best Practices flags app/views/projects/show.html.erb and tells you that you should move the logic into the controller.
• In the file config/rails_best_practices.yml, add the file app/views/projects/show.html.erb to the list of files to be ignored by MoveCodeIntoControllerCheck.
• Enter the command "sh git_check.sh". All tests should pass, and there should be no offenses.

Wrapping Up

• Enter the following commands:

git add .
git commit -m "Added project delete (view level)"
git push origin 05-07-project_delete

• Go to the GitHub repository and click on the "Compare and pull request" button for this branch.
• When you see that your app passes in continuous integration, accept this pull request to merge it with the master branch.
• Enter the following commands:

git checkout master
git pull