BDD, TDD Cycle

In this assignment you will use a combination of Behavior-Driven Design (BDD) and Test-Driven Development (TDD) with the Cucumber and RSpec tools to add a "find movies with same director" feature to RottenPotatoes, and deploy the resulting app on Heroku.

To get the initial RottenPotatoes code please fork this bdd-tdd-cycle repo to your GitHub account with the Fork button on GitHub. Then copy the clone URL from your repo, and execute the following command in the top level of your Cloud9 workspace:

git clone <your clone URL goes here>

Next, follow the instructions below to get setup:

  1. Change into the rottenpotatoes directory: cd hw-bdd-tdd-cycle/rottenpotatoes
  2. Run bundle install --without production to make sure all gems are properly installed.
  3. Run bundle exec rake db:migrate to apply database migrations.
  4. Finally, run these commands to set up the Cucumber directories (under features/) and RSpec directories (under spec/) if they don't already exist, allowing overwrite of any existing files:
rails generate cucumber:install capybara
rails generate cucumber_rails_training_wheels:install
rails generate rspec:install
  1. You can double-check if everything was installed by running the tasks rspec and cucumber.

Since presumably you have no features or specs yet, both tasks should execute correctly reporting that there are zero tests to run. Depending on your version of rspec, it may also display a message stating that it was not able to find any _spec.rb files.

Part 1: add a Director field to Movies

Create and apply a migration that adds the Director field to the movies table. The director field should be a string containing the name of the movie’s director. HINT: use the add_column method of ActiveRecord::Migration to do this.

Remember to add :director to the list of movie attributes in the def movie_params method in movies_controller.rb.

Remember that once the migration is applied, you also have to do rake db:test:prepare to load the new post-migration schema into the test database!

Part 2: use BDD+TDD to get new scenarios passing

We've provided three Cucumber scenarios to drive creation of the happy path of Search for Movies by Director. The first lets you add director info to an existing movie, and doesn't require creating any new views or controller actions (but does require modifying existing views, and will require creating a new step definition and possibly adding a line or two to features/support/paths.rb).

The second lets you click a new link on a movie details page "Find Movies With Same Director", and shows all movies that share the same director as the displayed movie.
For this you'll have to modify the existing Show Movie view, and you'll have to add a route, view and controller method for Find With Same Director.

The third handles the sad path, when the current movie has no director info but we try to do "Find with same director" anyway.

Going one Cucumber step at a time, use RSpec to create the appropriate controller and model specs to drive the creation of the new controller and model methods. At the least, you will need to write tests to drive the creation of:

  • a RESTful route for Find Similar Movies (HINT: use the 'match' syntax for routes as suggested in "Non-Resource-Based Routes" in Section 4.1 of ESaaS). You can also use the key :as to specify a name to generate helpers (i.e. search_directors_path) http://guides.rubyonrails.org/routing.html Note: you probably won’t test this directly in rspec, but a line in Cucumber or rspec will fail if the route is not correct.

  • a controller method to receive the click on "Find With Same Director", and grab the id (for example) of the movie that is the subject of the match (i.e. the one we're trying to find movies similar to)

  • a model method in the Movie model to find movies whose director matches that of the current movie. Note: This implies that you should write at least 2 specs for your controller: 1) When the specified movie has a director, it should... 2) When the specified movie has no director, it should ... and 2 for your model: 1) it should find movies by the same director and 2) it should not find movies by different directors.

It's up to you to decide whether you want to handle the sad path of "no director" in the controller method or in the model method, but you must provide a test for whichever one you do. Remember to include the line require 'rails_helper' at the top of your *_spec.rb files.

We want you to report your code coverage as well.

Add gem 'simplecov', :require => false to the test group of your gemfile, then run bundle install --without production.

Next, add the following lines to the TOP of spec/rails_helper.rb and features/support/env.rb:

require 'simplecov'
SimpleCov.start 'rails'

Now when you run rspec or cucumber, SimpleCov will generate a report in a directory named coverage/. Since both RSpec and Cucumber are so widely used, SimpleCov can intelligently merge the results, so running the tests for Rspec does not overwrite the coverage results from SimpleCov and vice versa.

To see the results in Cloud9, open /coverage/index.html. You will see the code, but click the Run button at the top. This will spin up a web server with a link in the console you can click to see your coverage report.

Improve your test coverage by adding unit tests and/or Cucumber features for untested or undertested code. Specifically, you can write unit tests for the update, destroy, and create controller methods, and perhaps bring in cucumber scenarios (and step definitions) from previous assignments.

Submission:

Here are the instructions for submitting HW4. Submit a zip file with various directories of your app:

  • app/
  • config/
  • db/migrate
  • features/
  • spec/
  • Gemfile Gemfile.lock

If you modified any other files, please include them too. If you are on a *nix based system, navigate to the root directory for HW4 and run

zip -r hw4.zip hw4/app/ hw4/config/ hw4/db/migrate hw4/features/ hw4/spec/ hw4/Gemfile hw4/Gemfile.lock

This will create the file hw4.zip, which you will submit.

IMPORTANT NOTE: Your submission must be zipped inside a hw folder so that it looks like so:

$ tree
.
└── hw4
    ├── Gemfile
    ├── Gemfile.lock
    ├── app
    ...