My data is basically Gallery(s) have many Picture(s), and Picture(s) belong_to a gallery. the pictures table has the foreign_key 'gallery_id'.
Although I`ve used has_many and belongs_to associations before, so I am not sure what I am doing wrong.
These are my relevant models:
class Gallery < ActiveRecord::Base
attr_accessible :name
has_many :pictures
belongs_to :home
end
class Picture < ActiveRecord::Base
belongs_to :gallery
validates :image, :presence => true
mount_uploader :image, ImageUploader
end
If I do this:
gallery = Gallery.create(:name => 'some name')
picture = Picture.create(:name => 'some name' , :image => 'some_image')
picture.gallery = gallery
this is true:
picture.gallery == #gallery
but this isnt
gallery.pictures == [ picture ]
because gallery.pictures returns an empty array.
On the other hand, if I create the picture this way, everything works as expected:
picture = Picture.create(:name => 'some name' , :image => 'some_image', :gallery_id => gallery)
Why? What I am doing wrong? I am using Rails 3.1.1 and sqlite
it should work
gallery.pictures.create :name => 'some name' , :image => 'some_image'
When adding pictures to your gallery. Try doing the assignment the other way around.
gallery = Gallery.create(:name => 'some name')
picture = Picture.create(:name => 'some name' , :image => 'some_image')
gallery.pictures << picture
This will update the #pictures method to return the newly assigned picture.
Related
Here's my code:
Models:
class Article < ActiveRecord::Base
attr_accessible :title, :author, :content, :imageable_attributes
has_one :image, as: :imageable, dependent: :destroy
accepts_nested_attributes_for :image, allow_destroy: true
validates_presence_of :title, :content, :author
end
class Image < ActiveRecord::Base
mount_uploader :image, ImageUploader
attr_accessible :image, :caption, :imageable_id, :imageable_type, :article_ref
validates_presence_of :image
belongs_to :imageable, :polymorphic => true
end
Here's what I've tried in console:
article = Article.create!(title: "test", content: "test", author: "test", image_attributes: {image: "test.jpg", caption: "test caption"})
This creates an Article without errors, but if I call:
article.image
I get:
=> nil
If I type in console:
article = Article.new(title: "test", content: "test", author: "test")
article.build_image(image: "test.jpg")
I get:
=> Validation failed: Image image can't be blank
Any help greatly appreciated, I'm very confused!
I believe it's necessary to supply the attachment itself, rather than just the path. As an example,
i = Image.new(
:image => File.join(Rails.root, "test.jpg")
)
i.image
# =>
but
i = Image.new(
:image => File.open(File.join(Rails.root, "test.jpg"))
)
i.image
# => /uploads/tmp/20120427-2155-1316-5181/test.jpg
It's not necessary to use File.open when saving using Multipart POST, though.
I have a ROR app that has many players, and many proposed games. The games display on a feed and a player can decide to hide them from this feed. The hidden function works like this:
in player.rb:
has_many :hides, :foreign_key=> "hider_id",
:dependent => :destroy
has_many :hidees, :through => :hides
def hidden?(hidee)
hides.find_by_hidee_id(hidee)
end
def hide!(hidee)
hides.create!(:hidee_id => hidee.id)
end
def unhide!(hidee)
hides.find_by_hidee_id(hidee).destroy
end
hides_controller.rb
class HidesController < ApplicationController
def create
#game = Game.find(params[:hide][:hidee_id])
current_profile.hide!(#game)
redirect_to :back
end
def destroy
#game = Hide.find(params[:id]).hidee
current_profile.unhide!(#game)
redirect_to :back
end
end
hide.rb
class Hide < ActiveRecord::Base
attr_accessible :hidee_id
belongs_to :hider, :class_name => "Player"
belongs_to :hidee, :class_name => "Game"
validates :hider_id, :presence => true
validates :hidee_id, :presence => true
end
game.rb
has_many :reverse_hides, :foreign_key => "hidee_id",
:class_name => "Hide",
:dependent => :destroy
has_many :hiders, :through => :reverse_hides
routes.rb
resources :games do
member do
post :publish
post :unpublish
get :view
get :hidees, :hiders
end
I'm trying to do two things: 1. Write a function that would allow me to hide a game from the feed if a relationship between hidden relationship between game and player exits, and 2. write a "show hidden" button that would allow me to return all projects that were "hidden" by the player.
So far with part 1. I have the following code in the view, and while this does the trick in terms of setting up the relationships, it does not "hide" the game from the feed--I'm guessing I would need ajax for that??
- if current_profile.hidden?(game)
= form_for current_profile.hides.find_by_hidee_id(game), :html => { :method => :delete } do |f|
= f.submit "Unhide", :title => "Unhide this game."
- else
= form_for current_profile.hides.build(:hidee_id => game.id) do |f|
= f.hidden_field :hidee_id
= f.submit "Hide", :title => "Hide this game"
Thank you so much for viewing this, I know it's quite long, but I would appreciate any help you could offer. Also, thank you for you time.
In my Rails 3 app I have two models, Profile and Item. Each has a HABTM relationship with the other. In my Profile model, I have a method wish_items that creates an Array of that same name (wish_items). If an item contains the category "wish", it is added to the wish_items Array for that profile.
For the purpose of this question, say I have an item named "phone" with category "wish". What I'd like to do is be able to find and count all Profiles that have "phone" in their wish_items Array so I can render that count in a view. My code is below.
My Profile.rb model:
class Profile < ActiveRecord::Base
has_and_belongs_to_many :items
def wish_items
wish_items = Array.new
items.each do |item|
if item.category == "wish"
wish_items << item
end
end
return wish_items
end
end
My Item.rb model:
class Item < ActiveRecord::Base
has_and_belongs_to_many :profiles
end
I have a join table items_profiles for this relationship. Here is that migration:
class CreateItemsProfiles < ActiveRecord::Migration
def self.up
create_table :items_profiles, :id =>false do |t|
t.references :item
t.references :profile
end
end
...
end
I saw this previous question and gave the answer a try but got an error NameError: uninitialized constant phone. Here is the code I tried from that:
Profile.all(:include => :items, :conditions => ["items.name = ?", phone])
Specifically I put that code in the following:
<%= pluralize(Profile.all(:include => :items, :conditions => ["items.name = ?", phone])).count, "person") %>
How can I do this?
The above was failing because I didn't have phone in quotations. Simple. The following worked:
Profile.all(:include => :items, :conditions => ["items.name = ?", "phone"])
And pluralizing:
<%= pluralize(Profile.all(:include => :items, :conditions => ["items.name = ?", "phone"]).count, "person") %>
I am looking to remove any duplicated tags being displayed and have a maximum number of 10 tags on display on the index page. Any suggestions on how I might do this?
/controller/tags_controller
class TagsController < ApplicationController
def show
#tag = Tag.limit(10).all
#tag = Tag.find(params[:id])
#articles = #tag.articles
end
end
end
model/tag.rb
class Tag < ActiveRecord::Base
validates :name, :uniqueness => true
#default_scope :order => 'created_at DESC'
has_many :taggings, :dependent => :destroy
has_many :articles, :through => :taggings
end
To avoir duplicate and to order by published date, in your tag model :
validates :name, :uniqueness => true
default_scope :order => 'created_at DESC'
To fetch the ten first tags, in your controller :
#tags = Tag.limit(10).all
Voila!
I'm building a small twitter style microblogging service where users can follow other users and get a feed of their messages
I have the following models:
class Follow < ActiveRecord::Base
belongs_to :follower, :class_name => "User"
belongs_to :followee, :class_name => "User"
end
class User < ActiveRecord::Base
has_many :follows, :foreign_key => 'follower_id',
:class_name => 'Follow'
has_many :followers, :through => :follows
has_many :followed, :foreign_key => 'followee_id',
:class_name => 'Follow'
has_many :followees, :through => :followed
has_many :messages
end
class Message < ActiveRecord::Base
belongs_to :user
end
To get a feed for the current user, I want to perform the following SQL query:
SELECT * FROM follows JOIN users JOIN messages WHERE follows.follower_id = current_user.id AND follows.followee_id = users.id AND users.id = messages.user_id;
What is the correct ActiveRecord way of doing this?
Not sure what you're looking for, but here is my suggestion:
I assume that you have other purposes for that Follow class, otherwise I don't see the purpose of it.
The "correct way" (i.e. my completely subjective way) to do it would actually be something like this:
class User < ActiveRecord::Base
has_and_belongs_to_many :followers, :foreign_key => 'followed_id',
:class_name => 'User', :association_foreign_key => 'follower_id',
:include => [:messages]
has_and_belongs_to_many :follows, :foreign_key => 'follower_id',
:class_name => 'User', :association_foreign_key => 'followed_id'
has_many :messages
end
class Message < ActiveRecord::Base
belongs_to :user
end
Then create the following table:
create_table :users_users, :id => false do |t|
t.integer :followed_id
t.integer :follower_id
end
And you're set:
followed = User.find :first
follower = User.find :last
followed.followers << follower
followed.followers.first.messages
followed.followers.first.followers.first.messages # etc...
But from what I make it, you want to show all the messages from all the followers at the same time.
This should be possible to achieve by adding
has_and_belongs_to_many :followed_messages, :foreign_key => 'follower_id',
:class_name => 'Message', :association_foreign_key => 'followed_id'
to the User class, but I don't know how correct that way would be. Or it might be possible to achieve with association extensions but there I can't really give any examples.
Update:
By changing the :class_name, it will associate it with the Message.id, didn't think about that so it will not be correct in this way.
So the only "nice" option is to go through the User class like in the first example.
The only other options I can see is either the association extensions (which I can't give you an example for) or perhaps using a finder statement.
has_many :followed_messages, :class_name => 'Message',
:finder_sql => 'select * from messages where user_id in(select followed_id from users_users where follower_id = #{id})'
You probably have to customize that sql statement to get everything to work, but at least you should get the picture :)
Keijro's arrangement would work better, though if you need the Follow table, then you can execute the SQL query you specified as follows:
Follow.all(:joins => { :messages, :users }, :conditions => { "follows.follower_id" => current_user.id, "follows.followee_id" => "users.id", "users.id" => "messages.user_id"} )