I have a User model, Post model and Bookmark model. How do i need to set up relationship among them so that I can use current_user.bookmarks.posts.
Maybe:
class User < ApplicationRecord
has_many :bookmarks
end
class Bookmark < ApplicationRecord
belongs_to :user
has_many :posts
end
class Post < ApplicationRecord
belongs_to :bookmark
end
If you're wanting to get all the posts that belong to the user, then you can use the has_many :through association:
class User < ApplicationRecord
has_many :bookmarks
has_many :posts, through: :bookmarks
end
class Bookmark < ApplicationRecord
belongs_to :user
has_many :posts
end
class Post < ApplicationRecord
belongs_to :bookmark
end
Then you can just call:
user = User.first
all_posts = user.posts
It will return an array containing all the posts for each of the bookmarks belonging to the user.
Related
Hi I'm trying to set up a many to many relationship in my app. I have two models Count.rb
class Count < ApplicationRecord
has_many :users, through: :counts_users
end
users.rb:
class User < ApplicationRecord
has_many :counts, through: :counts_users
end
and counts_users.rb:
class CountsUser < ApplicationRecord
belongs_to :user
belongs_to :count
end
Now I can create a count
Count.new(message: 'hello')
but if I then do
Count.last.users << User.last
I get the error ActiveRecord::HasManyThroughAssociationNotFoundError: Could not find the association :counts_users in model ErrorCount
I assume I've done something wrong setting up the association, but I'm not sure what?
Your models' associations should be set up like this:
# count.rb
class Count < ApplicationRecord
has_many :counts_users
has_many :users, through: :counts_users
end
# user.rb
class User < ApplicationRecord
has_many :counts_users
has_many :counts, through: :counts_users
end
# counts_user.rb
class CountsUser < ApplicationRecord
belongs_to :user
belongs_to :count
end
See: the Rails Guides on has_many :through Association
When I do #post = Post.first.comments.build(content: "bla", user: #user) and search via #user.comments nothing shows up. But when I do it with #post.comments, it lists the comment. How can I see my comment with both #user.comments and #post.comments?
class Post < ApplicationRecord
belongs_to :user
has_many :comments
end
my user model
class User < ApplicationRecord
has_many :posts
has_many :comments
end
comment model
class Comment < ApplicationRecord
belongs_to :user
belongs_to :post
end
use through to get comments of all posts associated with the user's posts.
class User
has_many :posts
has_many :comments, through: :posts
end
Here is my models:
class User < ActiveRecord::Base
has_many :products
has_many :comments
end
class Product < ActiveRecord::Base
belongs_to :user
has_many :comments
end
class Comment < ActiveRecord::Base
belongs_to :user
belongs_to :product
end
I need to get comment records from current user products only
How do I do that? thanks
If we move the relationships to use a has_many: comments, through: products you can probably get what you're after:
class User < ActiveRecord::Base
has_many :products
has_many :comments, through: products
end
class Product < ActiveRecord::Base
belongs_to :user
has_many :comments
end
class Comment < ActiveRecord::Base
belongs_to :user
belongs_to :product
end
Now you can do user.comments.
The rails docs are here, which say:
A has_many :through association is often used to set up a many-to-many
connection with another model. This association indicates that the
declaring model can be matched with zero or more instances of another
model by proceeding through a third model. For example, consider a
medical practice where patients make appointments to see physicians.
I have 3 Models: Place, User, Reviews. Place and Users related with has_many_belongs_to - for favorites, and has_many :through - for reviews.
I want to insert to favorites some place, but this place inserted to reviews table, what is wrong?
Or create model Favorites?
class Place < ActiveRecord::Base
has_and_belongs_to_many :users
has_many :reviews
has_many :users, through: :reviews
end
class User < ActiveRecord::Base
has_and_belongs_to_many :places
has_many :reviews
has_many :places, through: :reviews
end
class Review < ActiveRecord::Base
belongs_to :user
belongs_to :place
end
class FavoritesController < ApplicationController
def add_favorites
if User.first.places.push(Place.find(params[:place_id]))
render json: {desc:true, status:0, error:nil}
else
render json: {desc:false, status:1, error: "Problem insert to table places_users"}
end
end
Have you try having different names for the associations? Right now both your favorites and reviewed places are called the same.
Try something like:
class User < ActiveRecord::Base
has_and_belongs_to_many :favorite_places
has_many :reviews
has_many :reviewed_places, through: :reviews
end
And for the controller:
User.first.favorite_places.push(Place.find(params[:place_id]))
You could always use active record serializers to store a array of favorites ids in the User model.
class User < ActiveRecord::Base
serialize :favorites
end
user = User.create(favorites: [1, 4, 8, 9])
I have a model called company that has_many users then users belongs_to company.
class Company < ActiveRecord::Base
has_many :users
end
class User < ActiveRecord::Base
belongs_to :company
end
If something belongs to users will it also belong to company?
You have to use has_many :through association for this.
class Comment < ActiveRecord::Base
belongs_to :user
end
class User < ActiveRecord::Base
belongs_to :company
has_many :comments
end
class Company < ActiveRecord::Base
has_many :users
has_many :comments, :through => :users
end
Now you can do the following:
c = Company.first
c.users # returns users
c.comments # returns all the comments made by all the users in the company