Contents

A conventional architecture will have each component instantiate its own dependencies. For example, the @Application@ would do something like this:

<pre>
  class Application
    def initialize
      @logger = Logger.new
      @authenticator = Authenticator.new
      @database = Database.new
      @view = View.new
      @session = Session.new
    end
  end
</pre>

However, the above is already flawed, because the @Authenticator@ and the @Session@ both need access to the @Database@, so you really need to make sure you instantiate things in the right order and pass them as parameters to the constructor of each object that needs them, like so:

<pre>
  class Application
    def initialize
      @view = View.new
      @logger = Logger.new
      @database = Database.new( @logger )
      @authenticator = Authenticator.new( @logger, @database )
      @session = Session.new( @logger, @database )
    end
  end
</pre>

The problem with this is that if you later decide that @View@ needs to access the database, you need to rearrange the order of how things are instantiated in the @Application@ constructor.

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
needle-1.0.0	doc/manual/parts/03_conventional.txt
needle-1.2.0	doc/manual/parts/03_conventional.txt
needle-1.1.0	doc/manual/parts/03_conventional.txt
needle-0.9.0	doc/manual/parts/03_conventional.txt