Fix rubocop issues.

app/api/animal/api.rb

@@ -1,4 +1,5 @@
 module Animal
+  # Class with grape api for Animal project.
   class API < Grape::API
     version 'v1', using: :path
     format :json
@@ -19,20 +20,20 @@ def authenticate!
       user.valid_password? password if user
     end
 
-    desc 'Pet index.', {
-      params: Entities::Pet.documentation
-    }
+    desc 'Pet index.', params: Entities::Pet.documentation
     get '/pet' do
       authenticate!
       pets = Pet.all
       present pets, with: Entities::Pet, type: :full
     end
 
-    desc 'Create a pet.', {
-      params: Entities::Pet.documentation
-    }
+    desc 'Create a pet.', params: Entities::Pet.documentation
     params do
-      requires :all, except: [:id, :owner_email], using: Entities::Pet.documentation.except(:id, :owner_email)
+      requires(
+        :all,
+        except: [:id, :email],
+        using: Entities::Pet.documentation.except(:id, :email)
+      )
     end
     post '/pet' do
       authenticate!
@@ -41,18 +42,14 @@ def authenticate!
       end
     end
 
-    desc 'Breed index.', {
-      params: Entities::Breed.documentation
-    }
+    desc 'Breed index.', params: Entities::Breed.documentation
     get '/breed' do
       authenticate!
       breeds = Breed.all
       present breeds, with: Entities::Breed, type: :full
     end
 
-    desc 'Birth index.', {
-      params: Entities::Birth.documentation
-    }
+    desc 'Birth index.', params: Entities::Birth.documentation
     get '/birth' do
       authenticate!
       births = Birth.all

app/api/animal/entities.rb

@@ -1,26 +1,32 @@
 module Animal
+  # Entities for Animal API.
   module Entities
+    # General Entity with id, and timestamps.
     class Id < Grape::Entity
       expose :id
       expose :created_at
       expose :updated_at
     end
 
+    # General Entity plus name field.
     class Named < Id
       expose :name
     end
 
+    # Pet entity (Pet and Birth model).
     class Pet < Named
-      expose :owner_email
+      expose :email, as: :owner_email
       expose :breed_id
       expose :gender
       expose :father_id
       expose :mother_id
     end
 
+    # Breed entity like Breed model.
     class Breed < Named
     end
 
+    # Birth entity like Birth model.
     class Birth < Id
       expose :child_id
       expose :father_id

app/models/pet.rb

@@ -10,9 +10,7 @@ class Pet < ActiveRecord::Base
   validates :owner, presence: true
   validates :gender, presence: true
 
-  def owner_email
-    owner.email
-  end
+  delegate :email, to: :owner
 
   def birth
     Birth.find_by child: self

app/models/user.rb

@@ -6,6 +6,6 @@ class User < ActiveRecord::Base
          :recoverable, :rememberable, :trackable, :validatable
 
   def self.authorize!(env)
-    self.find_by email: env['REMOTE_USER']
+    find_by email: env['REMOTE_USER']
   end
 end

config/application.rb

@@ -31,7 +31,7 @@ class Application < Rails::Application
     config.active_record.raise_in_transactional_callbacks = true
 
     # Add REST API to app.
-    config.paths.add "app/api", glob: "**/*.rb"
+    config.paths.add 'app/api', glob: '**/*.rb'
     config.autoload_paths += Dir["#{Rails.root}/app/api/*"]
   end
 end