Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Open the newly created service object in the app/services/attachments_service.rb file and move the responsibility for uploading the file to the AttachmentsService#upload method."

A block of code is set as follows:

class AttachmentsService

  def upload(message_id, user_id, file_name, data, media_type)
    message = Message.find_by!(message_id, user_id: user_id)
    file = StorageBucket.files.create(
      key:  file_name,
      body: StringIO.new(Base64.decode64(data), 'rb'),
      public: true
    )

Any command-line input or output is written as follows:

brew install docker-compose

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Installing and managing a Kubernetes cluster is beyond the scope of this book. Luckily, a project called Minikube allows you to easily run a single-node Kubernetes cluster on your development machine."