module InheritedResources::BaseHelpers

Base helpers for InheritedResource work. Some methods here can be overwritten and you will need to do that to customize your controllers from time to time.

Protected Instance Methods

association_chain() click to toggle source

Returns the association chain, with all parents (does not include the current resource).

# File lib/inherited_resources/base_helpers.rb, line 130
def association_chain
  @association_chain ||=
    symbols_for_association_chain.inject([begin_of_association_chain]) do |chain, symbol|
      chain << evaluate_parent(symbol, resources_configuration[symbol], chain.last)
    end.compact.freeze
end
begin_of_association_chain() click to toggle source

This class allows you to set a instance variable to begin your association chain. For example, usually your projects belongs to users and that means that they belong to the current logged in user. So you could do this:

def begin_of_association_chain
  @current_user
end

So every time we instantiate a project, we will do:

@current_user.projects.build(params[:project])
@current_user.projects.find(params[:id])

The variable set in begin_of_association_chain is not sent when building urls, so this is never going to happen when calling resource_url:

project_url(@current_user, @project)

If the user actually scopes the url, you should use belongs_to method and declare that projects belong to user.

# File lib/inherited_resources/base_helpers.rb, line 116
def begin_of_association_chain
  nil
end
build_resource() click to toggle source

This method is responsible for building the object on :new and :create methods. If you overwrite it, don’t forget to cache the result in an instance variable.

# File lib/inherited_resources/base_helpers.rb, line 53
def build_resource
  get_resource_ivar || set_resource_ivar(end_of_association_chain.send(method_for_build, *resource_params))
end
collection() click to toggle source

This is how the collection is loaded.

You might want to overwrite this method if you want to add pagination for example. When you do that, don’t forget to cache the result in an instance_variable:

def collection
  @projects ||= end_of_association_chain.paginate(params[:page]).all
end
# File lib/inherited_resources/base_helpers.rb, line 24
def collection
  get_collection_ivar || begin
    c = end_of_association_chain
    set_collection_ivar(c.respond_to?(:scoped) ? c.scoped : c.all)
  end
end
create_resource(object) click to toggle source

Responsible for saving the resource on :create method. Overwriting this allow you to control the way resource is saved. Let’s say you have a PasswordsController who is responsible for finding an user by email and sent password instructions for him. Instead of overwriting the entire :create method, you could do something:

def create_resource(object)
  object.send_instructions_by_email
end
# File lib/inherited_resources/base_helpers.rb, line 67
def create_resource(object)
  object.save
end
destroy_resource(object) click to toggle source

Handle the :destroy method for the resource. Overwrite it to call your own method for destroying the resource, as:

def destroy_resource(object)
  object.cancel
end
# File lib/inherited_resources/base_helpers.rb, line 90
def destroy_resource(object)
  object.destroy
end
parent?() click to toggle source

Returns if the controller has a parent. When only base helpers are loaded, it’s always false and should not be overwritten.

# File lib/inherited_resources/base_helpers.rb, line 123
def parent?
  false
end
resource() click to toggle source

This is how the resource is loaded.

You might want to overwrite this method when you are using permalink. When you do that, don’t forget to cache the result in an instance_variable:

def resource
  @project ||= end_of_association_chain.find_by_permalink!(params[:id])
end

You also might want to add the exclamation mark at the end of the method because it will raise a 404 if nothing can be found. Otherwise it will probably render a 500 error message.

# File lib/inherited_resources/base_helpers.rb, line 45
def resource
  get_resource_ivar || set_resource_ivar(end_of_association_chain.send(method_for_find, params[:id]))
end
update_resource(object, attributes) click to toggle source

Responsible for updating the resource in :update method. This allow you to handle how the resource is going to be updated, let’s say in a different way than the usual :update:

def update_resource(object, attributes)
  object.reset_password!(attributes)
end
# File lib/inherited_resources/base_helpers.rb, line 79
def update_resource(object, attributes)
  object.update(*attributes)
end

Private Instance Methods

as_role() click to toggle source

getting role for mass-assignment

# File lib/inherited_resources/base_helpers.rb, line 374
def as_role
  { as: self.resources_configuration[:self][:role] }
end
build_resource_params() click to toggle source

extract attributes from params

# File lib/inherited_resources/base_helpers.rb, line 356
def build_resource_params
  parameters = permitted_params || params
  rparams = [parameters[resource_request_name] || parameters[resource_instance_name] || {}]
  if without_protection_given?
    rparams << without_protection
  else
    rparams << as_role if role_given?
  end

  rparams
end
method_for_association_build() click to toggle source

Returns the name of the method used for building the resource in cases where we have a parent. This is overwritten in singleton scenarios.

# File lib/inherited_resources/base_helpers.rb, line 199
def method_for_association_build
  :build
end
method_for_find() click to toggle source

Returns finder method for instantiate resource by params

# File lib/inherited_resources/base_helpers.rb, line 212
def method_for_find
  resources_configuration[:self][:finder] || :find
end
permitted_params() click to toggle source

Returns hash of sanitized params in a form like ‘{:project => {:project_attribute => ’value’}}‘

This method makes use of ‘project_params` (or `smth_else_params`) which is a default Rails controller method for strong parameters definition.

‘permitted_params` is usually fired by method :new, :create, :update actions. Action :new usually has no parameters so strong parameters `require` directive raises a ActionController::ParameterMissing exception. `#permitted_params` rescues such exceptions in :new and returns an empty hash of parameters (which is reasonable default). If for any reasons you need something more specific, you can redefine this method in a way previous `inherited_resources` versions did:

# Unnecessary redefinition
def permitted_params
  params.permit(:project => [:project_attribute])
end
# File lib/inherited_resources/base_helpers.rb, line 343
def permitted_params
  return nil  unless respond_to?(resource_params_method_name, true)
  {resource_request_name => send(resource_params_method_name)}
rescue ActionController::ParameterMissing
  # typically :new action
  if params[:action].to_s == 'new'
    {resource_request_name => {}}
  else
    raise
  end
end
resource_params() click to toggle source

memoize the extraction of attributes from params

# File lib/inherited_resources/base_helpers.rb, line 316
def resource_params
  @resource_params ||= build_resource_params
end
resource_params_method_name() click to toggle source
# File lib/inherited_resources/base_helpers.rb, line 320
def resource_params_method_name
  "#{resource_instance_name}_params"
end
resource_request_name() click to toggle source
# File lib/inherited_resources/base_helpers.rb, line 168
def resource_request_name
  self.resources_configuration[:self][:request_name]
end
role_given?() click to toggle source

checking if role given

# File lib/inherited_resources/base_helpers.rb, line 369
def role_given?
  self.resources_configuration[:self][:role].present?
end
smart_collection_url() click to toggle source

URL to redirect to when redirect implies collection url.

# File lib/inherited_resources/base_helpers.rb, line 304
def smart_collection_url
  url = nil
  if respond_to? :index
    url ||= collection_url rescue nil
  end
  if respond_to? :parent, true
    url ||= parent_url rescue nil
  end
  url ||= root_url rescue nil
end
smart_resource_url() click to toggle source

URL to redirect to when redirect implies resource url.

# File lib/inherited_resources/base_helpers.rb, line 295
def smart_resource_url
  url = nil
  if respond_to? :show
    url = resource_url rescue nil
  end
  url ||= smart_collection_url
end
with_chain(object) click to toggle source

Adds the given object to association chain.

# File lib/inherited_resources/base_helpers.rb, line 152
def with_chain(object)
  association_chain + [ object ]
end
without_protection() click to toggle source
# File lib/inherited_resources/base_helpers.rb, line 382
def without_protection
  { without_protection: self.resources_configuration[:self][:without_protection] }
end
without_protection_given?() click to toggle source
# File lib/inherited_resources/base_helpers.rb, line 378
def without_protection_given?
  self.resources_configuration[:self][:without_protection].present?
end