v0.3.0

computed_model 0.3 comes with a great number of improvements, and a bunch of breaking changes.

• Breaking changes
  • include ComputedModel is now include ComputedModel::Model.
  • Indirect dependencies are now rejected.
  • computed_model_error was removed.
  • dependency before define_loader will be consumed and ignored.
  • dependency before define_primary_loader will be an error.
  • Cyclic dependency is an error even if it is unused.
  • nil, true, and false in subdeps will be filtered out before passed to a loader.
  • ComputedModel.normalized_dependencies now returns [true] instead of [] as an empty value.
  • include_subdeps is now include_subfields
• Notable behavioral changes
  • The order in which fields are loaded is changed.
  • ComputedModel::Model now uses ActiveSupport::Concern.
• Changed
  • Separate ComputedModel::Model from ComputedModel #17
  • Remove computed_model_error #18
  • Improve behavior around dependency-field pairing #20
  • Implement strict field access #23
  • Preprocess graph with topological sorting #24
  • Implement conditional dependencies and subdependency mapping/passthrough #25
  • Use ActiveSupport::Concern #26
  • Rename subdeps as subfields #31
• Added
  • ComputedModel::Model#verify_dependencies
  • Loader dependency #28
  • Support computed model inheritance #29
• Refactored
  • Extract DepGraph from Model #19
  • Define loader as a singleton method #21
  • Refactor ComputedModel::Plan #22
• Misc
  • Collect coverage #12 #16
  • Refactor tests #10 #15
  • Add tests #27
  • Add documentation #30

See Migration-0.3.md for migration.

New feature: dynamic dependencies

Previously, subdeps are only useful for loaded fields and primary fields. Now computed fields can make use of subdeps!

class User
  # Delegate subdeps
  dependency(
    blog_articles: -> (subdeps) { subdeps }
  )
  computed def filtered_blog_articles
    if current_subfields.normalized[:image].any?
      # ...
    end
    # ...
  end
end

See CONCEPTS.md for more usages.

New feature: loader dependency

You can specify dependency from a loaded field.

class User
  dependency :raw_user  # dependency of :raw_books
  define_loader :raw_books, key: -> { id } do |subdeps, **|
    # ...
  end
end

New feature: computed model inheritance

Now you can reuse computed model definitions via inheritance.

module UserLikeConcern
  extends ActiveSupport::Concern
  include ComputedModel::Model

  dependency :preference, :profile
  computed def display_name
    "#{preference.title} #{profile.name}"
  end
end

class User
  include UserLikeConcern

  define_loader :preference, key: -> { id } do ... end
  define_loader :profile, key: -> { id } do ... end
end

class Admin
  include UserLikeConcern

  define_loader :preference, key: -> { id } do ... end
  define_loader :profile, key: -> { id } do ... end
end