Question

Recently we decided to make a general guideline for certain Rails3 project. And we experienced some troubles to formalize criteria: where code should be placed?

For models we end up with following:
Method should be added to the model if…

1. it changes attributes of the model.
2. it works as shortcut for long sequence of calls of model’s methods and has a good(semantic) name.
3. it redefine some functionality.
4. it needs to be inserted due to architectural issues.

Method should not be inserted if…

1. it is used for representing data (except cases when Aggregations work).
2. it is syntax sugar (syntax should be persistent)
3. it returns constant value (use constants or class variables)
4. it is alias for other method (use standard ruby ways to create aliases)
5. it has more-less complex logic and does not change anything in the db (move it to the lib)

What also can be added as criterion? Which books\articles covers such questions?

Answer 1

I highly recommend that you read Rails Antipatterns: Best Practice Ruby on Rails Refactoring. A lot of what you’ve covered here is discussed, but it’s more of a best practices book. A lot of the topics are fairly obvious if you’ve been working with Rails for a while, but it’s a great resource for “checking-in” on your coding practices. I’ve lent it to other developers on my team and they’ve given really positive feedback on it.