Rails 3 polymorphic_path - how to change the default route_key - ruby-on-rails-3

I got a config with Cart and CartItem (belongs_to :cart) models.
What I want to do is to call polymorphic_path([#cart, #cart_item]) so that it uses cart_item_path, instead of cart_cart_item_path.
I know I can change the url generated by the route to /carts/:id/items/:id, but that's not what I'm interested in. Also, renaming CartItem to Item is not an option. I just want to use cart_item_path method throughout the app.
Thanks in advance for any tip on that!
Just to make my point clear:
>> app.polymorphic_path([cart, cart_item])
NoMethodError: undefined method `cart_cart_item_path' for #<ActionDispatch::Integration::Session:0x007fb543e19858>
So, to repeat my question, what can I do in order for polymorphic_path([cart,cart.item]) to look for cart_item_path and not cart_cart_item_path?

After going all the way down the call stack, I came up with this:
module Cart
class Cart < ActiveRecord::Base
end
class Item < ActiveRecord::Base
self.table_name = 'cart_items'
end
def self.use_relative_model_naming?
true
end
# use_relative_model_naming? for rails 3.1
def self._railtie
true
end
end
The relevant Rails code is ActiveModel::Naming#model_name and ActiveModel::Name#initialize.
Now I finally get:
>> cart.class
=> Cart::Cart(id: integer, created_at: datetime, updated_at: datetime)
>> cart_item.class
=> Cart::Item(id: integer, created_at: datetime, updated_at: datetime)
>> app.polymorphic_path([cart, cart_item])
=> "/carts/3/items/1"
>> app.send(:build_named_route_call, [cart, cart_item], :singular)
=> "cart_item_url"
I think the same could work for Cart instead of Cart::Cart, with use_relative_model_naming? on the Cart class level.

You can declare the resources like this in your routes file.
resources :carts do
resources :cart_items, :as => 'items'
end
Refer to this section of the rails guide

Related

Rails form to edit JSON object as text

I'd like to make a form that lets a user edit one field of a mongoid object as rendered JSON text. There's a field in the model that my rails app should not understand, but I want to expose a generic editor. So for this field, I'd like to render it as pretty JSON, and expose it in a big <textarea> and then parse the JSON back in after any edits.
I can think of a dozen ways to do this, but I'm wonder what would be most consistent with Rails philosophy and least divergent from normal scaffolding. Should I render the object to JSON text in the controller? Then I'd have to repeat that code in the new and edit methods, and the parsing code in the update and create methods, which seems a bit kludgy. Is there a way to define a helper or custom form widget that goes in the _form.html.erb that is more reusable? Or maybe one already written?
You can make your own attribute writer/reader, in the model:
attr_accessible the_field_raw
def the_field_raw
self.the_field.to_s
end
def the_field_raw=(value)
self.the_field = JSON(value)
end
whitch should be compatible with form generators and no extra code in the controllers.
Hope it helps!
Serialize the values as JSON.
class Price < ActiveRecord::Base
serialize :values, JSON
validates :start, :end, :values, :presence => true
end
migration:
class CreateMyModels < ActiveRecord::Migration[7.0]
def change
create_table :my_models do |t|
t.jsonb :name, default: {}, null: false
t.jsonb :description, default: {}, null: false
t.integer :another_param
t.timestamps
end
end
end
model and concern:
class MyModel < ApplicationRecord
AVAILABLE_LOCALES = I18n.available_locales
include JsonLocalize
json_localize :name, :description
end
module JsonLocalize
extend ActiveSupport::Concern
included do
def self.json_localize(*attrs)
self::AVAILABLE_LOCALES.each do |locale|
attrs.each do |attr|
define_method("#{attr}_#{locale}") do
send(attr)[locale.to_s]
end
define_method("#{attr}_#{locale}=") do |value|
send(attr)[locale.to_s] = value
end
end
end
end
end
end
then you can have in your form:
.row
.col-md-6
- MyModel::AVAILABLE_LOCALES.each do |loc|
= f.input "name_#{loc}"
= f.input "description_#{loc}"
controller params:
def resource_params
params.require(:my_model).permit(
[
:another_param
] | [:name, :description].map {|attr| MyModel::AVAILABLE_LOCALES.map { |loc| "#{attr}_#{loc}".to_sym } }.flatten
)
end

FactoryGirl: why does attributes_for omit some attributes?

I want to use FactoryGirl.attributes_for in controller testing, as in:
it "raise error creating a new PremiseGroup for this user" do
expect {
post :create, {:premise_group => FactoryGirl.attributes_for(:premise_group)}
}.to raise_error(CanCan::AccessDenied)
end
... but this doesn't work because #attributes_for omits the :user_id attribute. Here is the difference between #create and #attributes_for:
>> FactoryGirl.create(:premise_group)
=> #<PremiseGroup id: 3, name: "PremiseGroup_4", user_id: 6, is_visible: false, is_open: false)
>> FactoryGirl.attributes_for(:premise_group)
=> {:name=>"PremiseGroup_5", :is_visible=>false, :is_open=>false}
Note that the :user_id is absent from #attributes_for. Is this the expected behavior?
FWIW, my factories file includes definitions for :premise_group and for :user:
FactoryGirl.define do
...
factory :premise_group do
sequence(:name) {|n| "PremiseGroup_#{n}"}
user
is_visible false
is_open false
end
factory :user do
...
end
end
Short Answer:
By design, FactoryGirl's attribues_for intentionally omits things that would trigger a database transaction so tests will run fast. But you can can write a build_attributes method (below) to model all the attributes, if you're willing to take the time hit.
Original answer
Digging deep into the FactoryGirl documentation, e.g. this wiki page, you will find mentions that attributes_for ignores associations -- see update below. As a workaround, I've wrapped a helper method around FactoryGirl.build(...).attributes that strips id, created_at, and updated_at:
def build_attributes(*args)
FactoryGirl.build(*args).attributes.delete_if do |k, v|
["id", "created_at", "updated_at"].member?(k)
end
end
So now:
>> build_attributes(:premise_group)
=> {"name"=>"PremiseGroup_21", "user_id"=>29, "is_visible"=>false, "is_open"=>false}
... which is exactly what's expected.
update
Having absorbed the comments from the creators of FactoryGirl, I understand why attributes_for ignores associations: referencing an association generates a call to the db which can greatly slow down tests in some cases. But if you need associations, the build_attributes approach shown above should work.
I think this is a slight improvement over fearless_fool's answer, although it depends on your desired result.
Easiest to explain with an example. Say you have lat and long attributes in your model. On your form, you don't have lat and long fields, but rather lat degree, lat minute, lat second, etc. These later can converted to the decimal lat long form.
Say your factory is like so:
factory :something
lat_d 12
lat_m 32
..
long_d 23
long_m 23.2
end
fearless's build_attributes would return { lat: nil, long: nil}. While the build_attributes below will return { lat_d: 12, lat_m: 32..., lat: nil...}
def build_attributes
ba = FactoryGirl.build(*args).attributes.delete_if do |k, v|
["id", "created_at", "updated_at"].member?(k)
end
af = FactoryGirl.attributes_for(*args)
ba.symbolize_keys.merge(af)
end
To further elaborate on the given build_attributes solution, I modified it to only add the accessible associations:
def build_attributes(*args)
obj = FactoryGirl.build(*args)
associations = obj.class.reflect_on_all_associations(:belongs_to).map { |a| "#{a.name}_id" }
accessible = obj.class.accessible_attributes
accessible_associations = obj.attributes.delete_if do |k, v|
!associations.member?(k) or !accessible.include?(k)
end
FactoryGirl.attributes_for(*args).merge(accessible_associations.symbolize_keys)
end
Here is another way:
FactoryGirl.build(:car).attributes.except('id', 'created_at', 'updated_at').symbolize_keys
Limitations:
It does not generate attributes for HMT and HABTM associations (as these associations are stored in a join table, not an actual attribute).
Association strategy in the factory must be create, as in association :user, strategy: :create. This strategy can make your factory very slow if you don't use it wisely.
The accepted answer seems outdated as it did not work for me, after digging through the web & especially this Github issue, I present you:
A clean version for the most basic functionality for Rails 5+
This creates :belongs_to associations and adds their id (and type if :polymorphic) to the attributes. It also includes the code through FactoryBot::Syntax::Methods instead of an own module limited to controllers.
spec/support/factory_bot_macros.rb
module FactoryBot::Syntax::Methods
def nested_attributes_for(*args)
attributes = attributes_for(*args)
klass = args.first.to_s.camelize.constantize
klass.reflect_on_all_associations(:belongs_to).each do |r|
association = FactoryBot.create(r.class_name.underscore)
attributes["#{r.name}_id"] = association.id
attributes["#{r.name}_type"] = association.class.name if r.options[:polymorphic]
end
attributes
end
end
this is an adapted version of jamesst20 on the github issue - kudos to him 👏

Retrieving an ActiveRecord length validation returns nil

I want to retrieve the maxmimum lenght validation of a ActiveRecord field in one of my views.
The following works fine in rails console and returns the correct value :
irb(main):046:0> micropost = Micropost.new
=> #<Micropost id: nil, content: nil, user_id: nil, created_at: nil, updated_at: nil>
irb(main):047:0> micropost._validators[:content][1].options[:maximum].to_s
=> "140"
However, when I use the same code in my controller it returns nil :
class PagesController < ApplicationController
def home
#title = "Home"
if signed_in?
#micropost = Micropost.new
#feed_items = current_user.feed.paginate(:page => params[:page])
#content_max = #micropost._validators[:content][1].options[:maximum].to_s
end
end
...
end
I also tried to include a method in my ApplicationHelper, which also returns nil ;-(
def content_max
Micropost._validators[:content][1].options[:maximum].to_s
end
What am I doing wrong?
The _validators array might not be in the same order whether you're in the console or in a web request.
Micropost._validators[:content].find {|v| v.class == ActiveModel::Validations::LengthValidator} .options[:maximum].to_s
should do what you want.
IMHO, a better solution would be to store the length in a constant (I somehow doubt the _validators array is part of the official API) :
class Micropost < ActiveRecord::Base
MAX_CONTENT_LENGTH = 140
validates :content, :length => {:maximum => MAX_CONTENT_LENGTH}
# Rest of the code...
end
and get the length with :
Micropost::MAX_CONTENT_LENGTH

Active Record Querying belong_to

I have the two following models associated:
class Post < ActiveRecord::Base
belongs_to :language
end
class Language < ActiveRecord::Base
has_many :posts
end
From a view I have a link to filter the posts by language:
<div id="english"><%= link_to "English", {:controller => 'posts', :action => 'search_result', :language => "english"} %></div>
The model language has a variable name:string which is the one i am using to make the active record query.
The doubt i have is how i can make this query from the post controller to retrieve the right posts which has a field: language.name == "english".
I tried this:
#posts = Post.all(:conditions => ["language.name = ?", params[:language]])
and also this:
#posts = Post.where(:language.name => params[:language])
Hope i have explained well the issue, i am a quite newbie yet. Ah! i would also know what would it be better in this case to use: "all" or "where" ??.
Thanks a lot in advance.
You need to do a join: http://guides.rubyonrails.org/active_record_querying.html#specifying-conditions-on-the-joined-tables
If I have understood your models/database structure correctly, the ActiveRecord call should looks something like:
Post.joins(:language).where('languages.name' => params[:language])
Hope that helps.
PS. The where call is the preferred method these days.

override to_xml to limit fields returned

using ruby 1.9.2 and rails 3, i would like to limit the fields returned when a record is accessed as json or xml (the only two formats allowed).
this very useful post introduced me to respond_with and i found somewhere online that a nice way to blanket allow/deny some fields is to override as_json or to_xml for the class and set :only or :except to limit fields.
example:
class Widget < ActiveRecord::Base
def as_json(options={})
super(:except => [:created_at, :updated_at])
end
def to_xml(options={})
super(:except => [:created_at, :updated_at])
end
end
class WidgetsController < ApplicationController
respond_to :json, :xml
def index
respond_with(#widgets = Widgets.all)
end
def show
respond_with(#widget = Widget.find(params[:id]))
end
end
this is exactly what i am looking for and works for json, but for xml "index" (GET /widgets.xml) it responds with an empty Widget array. if i remove the to_xml override i get the expected results. am i doing something wrong, and/or why does the Widgets.to_xml override affect the Array.to_xml result?
i can work around this by using
respond_with(#widgets = Widgets.all, :except => [:created_at, :updated_at])
but do not feel that is a very DRY method.
In your to_xml method, do the following:
def to_xml(options={})
options.merge!(:except => [:created_at, :updated_at])
super(options)
end
That should fix you up.