Decoration is best, except when it isn’t:

Decoration and module extension are both viable ways to compose objects in Ruby. Which to use is not a simple black-or-white choice; it depends on the purpose of the composition.

For applications where you want to adorn an object with some extra functionality, or modify how it presents itself, a decorator is probably the best bet. Decorators are great for creating Presenters, where we just want to change an object’s “face” in a specific context.

On the other hand, when building up a composite object at runtime object out of individual “aspects” or “facets”, module extension may make more sense. Judicious use of module extension can lead to a kind of “emergent behavior” which is hard to replicate with decoration or delegation.

Crazy, Heretical, and Awesome: The Way I Write Rails Apps | James on Software:

To decouple the logging from the creation of the database record, we’re going to use something called a service object. A service object is typically used to coordinate two or more objects; usually, the service object doesn’t have any logic of its own (simplified definition). We’re also going to use Dependency Injection so that we can mock everything out and make our tests awesomely fast (seconds not minutes).

Source: @brynary

Sandi Metz: SOLID Design Principles – Dependency Injection:

Because of the style of coding in Job, it contains dependencies that effect my ability to refactor and reuse it in the future.

Source: brynary

A Bit More About the New Joyent Cloud API:

To solve this problem with SmartDataCenter, we’re introducing the HTTP Signature authentication scheme, which is already released as open source. The HTTP Signature scheme allows for digital signatures to be leveraged as your credentials, and does not imply any particular key management scheme. It should be suitable for just about any REST API out there, so we’re certainly hoping if you’re an API vendor you take a look at it, but rather than jump into the technical details of the spec itself, I thought it would be interesting to show you some CLI candy, so lets walk through some examples.

Source: Joyeur

Ruby On REST: Introducing the Representer Pattern:

The calls for more object-orientation in Ruby frameworks are growing ever louder. Most web frameworks, like Rails, come with a nice database abstraction, a Rack-like HTTP endpoint, routing, and a template engine. It’s the lack of additional abstraction layers that make many programmers ask for “more OOP”.

Your Rails Application is Missing a Domain Controller:

When an application has multiple Domain Controllers I place them in a dedicated directory under app called services to keep them separate from the Model entities in app/models. This helps communicate that Rails Action Controllers should delegate to the Domain Controllers, not directly to Model Entities. The Domain Controllers and Model Entities together, represent the domain layer of the system. I have also discussed extracting the entire domain layer from the Rails framework, but that’s another discussion. Let’s keep this blog post civil for now!