Sending a file upload to s3 with Fog, and writing a spec with Fog's built-in mocks, on Rails 4

controller.rb

storage = Fog::Storage.new(
    provider: 'AWS',
    aws_access_key_id: 'xxx',
    aws_secret_access_key: 'yyy',
    path_style: true
)

directory = storage.directories.get('yourbucket')
uploaded = directory.files.create(
    key: "324324.jpg",
    body: params[:uploaded_file],
    public: true
)

spec.rb

ENV['AWS_ACCESS_KEY_ID'] = 'xxx'
ENV['AWS_SECRET_ACCESS_KEY'] = 'yyy'

Fog.mock!
Fog::Mock.reset

@s3 = Fog::Storage.new(
    provider: 'AWS',
    aws_access_key_id: 'xxx',
    aws_secret_access_key: 'yyy',
    path_style: true # for bucket names containing periods
)
@s3.directories.create(key: 'yourbucket')

post :receive_file, uploaded_file: fixture_file_upload('yaketyyak.jpg', 'some/mimetype')

bucket = @s3.directories.get('yourbucket')
expect(bucket.files.count).to eq 1

file = bucket.files.get("324324.jpg")
expect(file).to be_present
expect(file.body).to eq File.read('spec/fixtures/yaketyyak.jpg')
expect(file.public_url).to eq 'http://bucketname/324234.jpg'