Rspec with DatabaseCleaner

database_cleaner.rb

# spec/support/database_cleaner.rb

RSpec.configure do |config|
  # We don't use Rails' transactional tests because we use DatabaseCleaner instead.
  # http://weilu.github.io/blog/2012/11/10/conditionally-switching-off-transactional-fixtures/
  config.use_transactional_tests = false

  TABLES_NOT_TO_TRUNCATE = %w[
    schema_migrations
    ar_internal_metadata
  ]

  config.before(:suite) do
    DatabaseCleaner.clean_with :truncation, except: TABLES_NOT_TO_TRUNCATE
    Rails.application.load_seed
  end

  def require_transaction_for(example)
    example.metadata[:requires_transaction] ||
      example.metadata[:js]
  end

  config.before(:each) do |example|
    DatabaseCleaner.strategy = if require_transaction_for(example)
                                 [:truncation, { except: TABLES_NOT_TO_TRUNCATE }]
                               else
                                 :transaction
                               end
    DatabaseCleaner.start
  end

  config.after do |example|
    DatabaseCleaner.clean
    Rails.application.load_seed if require_transaction_for(example)
  end
end

example_spec.rb

# An example group that needs the transaction to be closed in order to pass.

context "DELETE destroy", :requires_transaction do
  let(:the_request) { delete "/admin/sites/#{site.id}" }
  let!(:site) { FactoryGirl.create(:site) }

  it "deletes the site" do
    the_request
    expect { site.reload }.to raise_error(ActiveRecord::RecordNotFound)
  end
end

spec_helper.rb

# This example assumes that you have the following line uncommented in your spec_helper:

Dir[Rails.root.join('spec/support/**/*.rb')].each { |f| require f }