I need to clean up my code from using:
# class ProjectsController < ApiController
def show
render json: Project.find_by(id: params[:id]).as_json(include: :user)
end
to:
render json: Project.find_by(id: params[:id]) // should include the association
Is there a way to put this logic in the model? Im using Rails 5 API
class Project < ApplicationRecord
belongs_to :user, include: :project // I thought this would work
def self.foo
self.includes(:user)
end
end
# in controller
render json: Project.foo.find_by(id: params[:id]) // nothing
What if Project belongs to many models and to need to include it by only calling Project.find(1), I will have some nested includes in my controller. Could I put all this logic in the model then Project.find(1) would show all the associations in json format?
In your Project model, override as_json method to include association user:
def as_json(options = {})
super(include: :user)
end
Related
More specifically, if I have two options: do a check in the controller or override an association method in the model, which one should I prefer?
Edit:
class Book < ApplicationRecord
belongs_to :author
def author
super || build_author
end
end
Is the code above ok or should I prefer another solution like the one below?
class BooksController < ApplicationController
def update
set_author
if #book.update_attributes(params[:book])
#redirect
else
#render show page - unprocessable entity
end
end
def set_author
a = Author.where(fields)
#book.author = a || #book.build_author
end
end
How do I add parameters to methods for rendering the current place in favorites?
I tried this:
class Place < ActiveRecord::Base
has_and_belongs_to_many :users
def in_fav(user)
if user.places.include?Place.find(id)
return true
else
return false
end
end
end
class User < ActiveRecord::Base
has_and_belongs_to_many :places
end
class PlacesController < ApplicationController
places = Place.all
user = User.first
render json: {desc:true, status:1; data: places}.to_json(:methods => :in_fav(user))
end
I find same problem here
attr_accessor :current_user
def is_favorited_by_user?(user=nil)
user ||= current_user
end
#drops.current_user = current_user
render :json => #drops.to_json(:methods => :is_favorited_by_user?)
I don't understand current_user - it's assocciations? and how to use method current_user for collection #drops
Basically my idea is very simple - I want to create a new cart for each new user. The form itself is generated with scaffold and we're talking rails 4.0.1 here.
Is there a way to do that and if so - how? Maybe you can link me some live examples?
You do not need multiple forms to create multiple objects in Rails controller. Assuming that you have relationships like this:
class User < ActiveRecord::Base
has_many :carts #or has_one :cart
end
class Cart < ActiveRecord::Base
belongs_to :user
end
Then it's perfectly acceptable to do this:
class UsersController < ApplicationController
def new
#user = User.new
end
def create
#user = User.new user_params
if #user.save
#user.carts.create # or #user.create_cart
redirect_to user_path
else
render action: :new
end
end
private
def user_params
params.require(:user).permit(...)
end
end
If the new user form happens to include some cart-specific details, then use fields_for to make them available in the form:
= form_for :user do |f|
... f.blah for user fields ...
= fields_for :cart do |cart_fld|
... cart_fld.blah for cart fields ...
and add cart_params to your controller.
I have set up an event booking application with ruby on rails where I have users who can create events and the general public can book events. I am having problems implementing the booking feature. This is what I have done so far.
Created a Booking resource and associated it with the event model. The booking model contains the following attributes
Booker name
Booker Email
event_id
The goal is to "create a booking" for a current event. However I do not know how to pass the "current_event" parameter to the booking controller and I am also not sure how to define a "current_event".
Update your routes file like this (rails 4):
EventManagement::Application.routes.draw do
resources :events do
resources :bookings
end
end
This will give you a "nested route" -- the route to bookings is always "nested" under events. To create a new booking for an event, you'll use the new_event_booking_path(#event) route and to view a list of all the bookings for the event it's just event_bookings_path(#event). Each of these routes will put the event_id into the params hash.
class BookingsController < ApplicationController
before_filter :load_event
def index
#bookings = #event.bookings
end
def new
#booking = #event.bookings.build
end
def create
#booking = #event.bookings.build booking_params
if #booking.save
..
else
...
end
end
private
def load_event
#event = Event.find params[:event_id]
end
def bookings_params
params.require(:bookings).permit(:booker_name, :booker_email)
end
end
Actually I don't think you should have a Booking resource, but rather an Event resource and only a Booking model. The booking should happen in the events_controller, where you can easily specify the current #event.
Were I you, I would do the following.
# app/models/event.rb
class Event < ActiveRecord::Base
has_many :bookings
end
# /models/booking.rb
class Booking < ActiveRecord::Base
belongs_to :event
end
# app/controllers/events_controller.rb
class EventsController < ApplicationController
# POST /events/{:id}/book
def book_new_ticket
#event = Event.find(params[:id])
if #event.bookings.where(email: params[:email]).count > 0
redirect_to '/somewhere', alert: "THIS EMAIL HAS ALREADY BOOKED, YOU FOOL!"
else
Booking.create!(name: params[:name], email: params[:email], event_id: #event.id)
end
end
end
Haven't really run this code, but it's just a simulation.
If I have a nested resource like so:
resources :users
resources :posts
end
and a user has_many posts, it is possible to have Rails start numbering based on the parent association in the URL? For example, currently, nesting resources just grabs the ID:
#user.posts.find(params[:id])
This correctly namespaces the posts, only allowing posts from #user... however, is there a way such that the post_id is independent? I.E. I want each user's posts to start at 1, where:
/users/1/posts/1
/users/2/posts/1
Actually refer to two different posts?
It can be quite a bit of work, but basically you can do it with these steps:
Create a migration to add a new attribute to store the specific user-post count. (I used user_post_id)
Override Post's to_param method to use the new value you just created. (It has to be a string.)
to_param is the method that the url and path helpers use.
Create a before_save filter that will actually increment the user_post_id value for each new post.
Change all your controller methods to find on user_post_id
#user = User.find(params[:user_id])
#post = #user.posts.where(:user_post_id => (params[:id])).first
Change all your Views that might not work now
You can see the source here: Custom Nested Resource URL example
Code
migration:
class AddUserPostIdToPosts < ActiveRecord::Migration
def change
add_column :posts, :user_post_id, :integer
end
end
post.rb:
class Post < ActiveRecord::Base
before_save :set_next_user_post_id
belongs_to :user
validates :user_post_id, :uniqueness => {:scope => :user_id}
def to_param
self.user_post_id.to_s
end
private
def set_next_user_post_id
self.user_post_id ||= get_new_user_post_id
end
def get_new_user_post_id
user = self.user
max = user.posts.maximum('user_post_id') || 0
max + 1
end
end
A couple controller methods
posts_controller.rb:
class PostsController < ApplicationController
respond_to :html, :xml
before_filter :find_user
def index
#posts = #user.posts.all
respond_with #posts
end
def show
#post = #user.posts.where(:user_post_id => (params[:id])).first
respond_with [#user, #post]
end
...
end