Q2. Within a Rails controller, which code will prevent the parent controller's before_action :get_feature from running?
skip_before_action :get_feature
skip :get_feature, except: []
prevent_action :get_feature
:redis_cache_store
Q3. Which statement correctly describes a difference between the form helper methods form_tag and form_for?
The form_tag method is for basic forms, while the form_for method is for multipart forms that include file uploads.
The form_tag method is for HTTP requests, while the form_for method is for AJAX requests.
The form_tag method typically expects a URL as its first argument, while the form_for method typically expects a model object.
The form_tag method is evaluated at runtime, while the form_for method is precompiled and cached.
Q4. What is before_action (formerly known as before_filter)?
A trigger that is executed before an alteration of an object's state
A method that is executed before an ActiveRecord model is saved
A callback that fires before an event is handled
A method in a controller that is executed before the controller action method
Q5. Which module can you use to encapsulate a cohesive chunk of functionality into a mixin?
ActiveSupport::Concern
RailsHelper.CommonClass
ActiveJob::Mixin
ActiveSupport::Module
Q6. In Rails, which code would you use to define a route that handles both the PUT and PATCHREST HTTP verbs?
put :items, include: patch
put 'items', to: 'items#update'
match 'items', to 'items#update', via: [:put, :patch]
match :items, using: put && patch
Q7. Which choice includes standard REST HTTP verbs?
GET, POST, PATCH, DELETE
REDIRECT, RENDER, SESSION, COOKIE
INDEX, SHOW, NEW, CREATE, EDIT, UPDATE, DESTROY
CREATE, READ, UPDATE, DELETE
Q8. Which ActiveRecord query prevents SQL injection?
Product.where("name = #{@keyword}")
Product.where("name = " << @keyword}
Product.where("name = ?", @keyword
Product.where("name = " + h(@keyword)
Q9. Given this code, which statement about the database table "documents" could be expected to be true?
class Document < ActiveRecord::Base
belongs_to :documentable, polymorphic: true
end
class Product < ActiveRecord::Base
has_many :documents, as: :documentable
end
class Service < ActiveRecord::Base
has_many :documents, as: :documentable
end
It would include a column for :type.
It would include columns for :documentable_id and :documentable_type.
It would include columns for :documentable and :type.
It would include a column for :polymorphic_type.
Q10. Are instance variables set within a controller method accessible within a view?
Yes, any instance variables that are set in an action method on a controller can be accessed and displayed in a view.
Yes, instance variables set within an action method are accessible within a view, but only when render is explicitly called inside the action method.
No, instance variables in a controller are private and are not accessible.
No, instance variables can never be set in a controller action method.
Q11. When a validation of a field in a Rails model fails, where are the messages for validation errors stored?
my_model.errors[:field]
my_model.get_errors_for(:field)
my_model.field.error
my_model.all_errors.select(:field)
Q12. If a database table of users contains the following rows, and id is the primary key, which statement would return only an object whose last_name is "Cordero"?
Q24. Given this controller code, which choice describes the expected behavior if parameters are submitted to the update action that includes values for the product's name, style, color, and price?
class ProductController < ActionController::Base
def update
@product = Product.find(params[:id])
if @product.update_attributes(product_params)
redirect_to(product_path(@product))
else
render('edit')
end
end
private
def product_params
params.require(:product).permit(:name, :style, :color)
end
end
The product will not be updated and the edit template will be rendered.
The product will not be updated and the controller will raise an ActiveModel::ForbiddenAttributes exception.
The product will be updated with the values for name, style, and color, but the value for price will be ignored.
The product will be updated with the values for name, style, color, and price.
Q25. A Rails project has ActiveRecord classes defined for Classroom and Student. If instances of these classes are related so that students are assigned the ID of one particular classroom, which choice shows the correct associations to define?
A
class Classroom < ActiveRecord::Base
belongs_to :students, class_name: 'Student'
end
class Student < ActiveRecord::Base
belongs_to :classrooms, class_name: 'Classroom'
end
B
class Student < ActiveRecord::Base
has_many :classrooms, dependent: true
end
class Classroom < ActiveRecord::Base
has_many :students, dependent: false
end
C
class Student < ActiveRecord::Base
has_many :classrooms
end
class Classroom < ActiveRecord::Base
belongs_to :student
end
D
class Classroom < ActiveRecord::Base
has_many :students
end
class Student < ActiveRecord::Base
belongs_to :classroom
end
Q26. Where should you put images, JavaScript, and CSS so that they get processed by the asset pipeline?
