Coding session
Good Things
-
Controller logic to Models
- Models logic to Modules
- -
- View logic to Decorators
- View logic to Helpers
Why Good ?
- Skinny Controllers -> Readable
- Models -> Reusable
- Modules -> Single Responsability
- Decorators -> Readable
Bad Things
- Naming
- Namespacing
- Big Methods
Naming
-
What 'Paginate' should do ?
- Actually, 'Paginate' is a module that define behavior for pagination
- Possible good naming could be 'Paginable'
Naming
- What 'pool_url' should do ?
- Actually, its display not only the url, but the full link tag
- Possible good naming could be just 'pool', as its belongs in a decorator
Facing Problems
- What to refactor
- What priority
- Make a "junk" module OR severals skinny modules
- Refactoring too fast
What to refactor and priority
- Controller logic into Models
- View logic into Decorators
- Models logic into Modules
- View logic into Helpers
- Helpers & Modules into namespaced Class
The END ?
AREL + Active Record
-
AREL = Relational Algebra
- Active Record = ORM
- -
- AREL means Active Relation
- ORM means Object-Relational Mapping
How the logic works
- AREL construct the query
- users = User.where(admin: true)
- This is not a collection, it's an ActiveRelation object
- ordered_users = user.order("name ASC")
- -
- ActiveRecord perform the query an translate it into ruby
- users = users.all.to_a
- This is a collection of User
- Method 'to_a' force the query to be executed and wrapped in a collection
Coding !
- Make an simple AREL/ActiveRecord yourself !
- Complete the ArticlesController#coding_arel method
- http://192.168.10.10:3000/articles/coding_arel
- -
- Hint : Keep it simple (to code, and to use)
- Hint : Use Model.find_by_sql("query") to perform SQL
- Hint : Use ActiveSupport::Inflector#tableize
- Hint : Use ActiveRelation#to_sql to see SQL syntax
- -
- When you'r done, refactor (step by step)
Coding session - review
By Thomas Petrachi