```ruby
require 'spec_helper'

describe 'deploy a staticfile app' do
  let(:app) { Machete.deploy_app('staticfile_app') }
  let(:browser) { Machete::Browser.new(app) }

  after do
    Machete::CF::DeleteApp.new.execute(app)
  end

  specify do
    expect(app).to be_running

    browser.visit_path('/')
    expect(browser).to have_body('This is an example app for Cloud Foundry that is only static HTML/JS/CSS assets.')
  end
end
```

Test that json files are served with correct mime type
user
```ruby
require 'spec_helper'

describe 'deploy a staticfile app' do
  let(:app) { Machete.deploy_app('staticfile_app') }
  let(:browser) { Machete::Browser.new(app) }

  after do
    Machete::CF::DeleteApp.new.execute(app)
  end

  specify do
    expect(app).to be_running

    browser.visit_path('/')
    expect(browser).to have_body('This is an example app for Cloud Foundry that is only static HTML/JS/CSS assets.')
    
    contents, _, _ = Open3.capture3('curl staticfile-app.10.244.0.34.xip.io/fixture.json -I')
    expect(contents).to include('Content-Type: application/json')
  end
end
```
assistant