I have multiple belongs_to relationships to the same model. Modeling messages between two users as follows (in the Message model):
belongs_to :to, :class_name => 'User', :foreign_key => 'to_id'
belongs_to :from, :class_name => 'User', :foreign_key => 'from_id'
attr_accessible :to, :from # ...
The corresponding has_many calls are in the User model. Everything works in the spec and the console as I need it to, with the exception of the following deprecation warning (for both from_id and to_id):
DEPRECATION WARNING: You're trying to create an attribute `from_id'. Writing arbitrary attributes on a model is deprecated. Please just use `attr_writer`
The relevant spec follows:
it "can associate users" do
User.delete(:all)
ufrom = FactoryGirl.create(:DrKevorkian)
ufrom.save!
uto = FactoryGirl.create(:JohnSmith)
uto.save!
m = Message.new
m.from = ufrom # <-- Warning here
m.to = uto # <-- Warning here
m.save
m.from.id.should == ufrom.id
m.to.id.should == uto.id
end
It seems to me the warning is happening as a result of the belongs_to association -- is there a cleaner/better way to do this?
Thanks very much.
My experience is that you get this warning if you forgot to run rake db:migrate and rake db:test:prepare after changing your schema.
Related
I am having performance issues on one of my api views so I ran the Bullet gem and found some major N+1 issues with the view.
The api is being consumed so the format has to remain identical.
Bullet N+1 output:
localhost:3000/api/v1/games/1/game_feed N+1 Query detected
CompletedQuest => [:comments] Add to your finder: :include =>
[:comments] N+1 Query method call stack
/app/views/api/v1/games/game_feed.json.jbuilder:3:in block in
_b3b681b668d1c2a5691a5b3f7c15bb8e' /app/views/api/v1/games/game_feed.json.jbuilder:1:in
_b3b681b668d1c2a5691a5b3f7c15bb8e'
But I don't know how to accomplish the fix. Here are the relevant parts.
View:
json.game_feed(#game_photos) do |f|
json.extract! f, :id, :user_id, :username, :image_url_original, :comments_count, :likes_count
json.comments f.comments do |comment|
json.(comment, :username, :comment)
end
json.likes f.likes do |like|
json.(like, :id, :user_id, :username)
end
end
Controller:
#game_photos = CompletedQuest.game_photos(#game.id)
Model:
def self.game_photos(game_id)
where("completed_quests.game_id = ?", game_id).order("completed_quests.id DESC").just_photos
end
scope :just_photos, -> { where.not( image_file_name: nil ) }
Model relationships:
# CompletedQuests:
belongs_to :user
has_many :comments, dependent: :destroy
has_many :likes, dependent: :destroy
# Comments:
belongs_to :completed_quest, counter_cache: true
belongs_to :user
So basically for each photo in the feed, it then grabs every comment & likes for ever record - obviously this is bad and I see why, but I can't figure out how to fix it with my current structure.
Any help would be appreciated - but one thing is the structure of the JSON must remain identical.
You could include the associated comments in the query as follows:
# app/models/completed_quest.rb
def self.game_photos(game_id)
includes(:comments).where("completed_quests.game_id = ?", game_id).order("completed_quests.id DESC").just_photos
end
This will include all the associated comments in the result, so when you do f.comments in your view, there won't be a database query for comments of each f instance.
This is EXTREMELY bizarre. I'm upgrading a Rails 2.3.12 app and running into this same problem over and over again. I'm stumped and nothing else out there seems to touch on it.
I have two models:
class User < ActiveRecord::Base
has_many :logs, :class_name => 'UserLog'
end
and
class UserLog < ActiveRecord::Base
attr_accessor :site_id, :controller, :action, :url, :session
belongs_to :user
validates_presence_of :user
end
then in another controller I'm doing this:
def log_user_activity
#current_user.logs.create(:site_id => #site.id, :controller => params[:controller],
:action => params[:action], :url => request.path,
:session => request.session_options[:id]) if #current_user
end
as you can see, it's pretty straightforward but when I call log_user_activity I'm getting this:
Can't mass-assign protected attributes: site_id, controller, action, url, session
HOWEVER, if I change all my creates or builds to this:
def log_user_activity
log = #current_user.logs.new
log.site_id = #site.id
log.controller = params[:controller]
log.action = params[:action]
log.url = request.path
log.session = request.session_options[:id]
log.save
end
then it works fine!?
Has anyone seen this? Any clues?
In class UserLog, add the following:
attr_accessible :site_id, :controller, :action, :url, :session
The reason you have to use attr_accessible is most likely because you are utilizing a plugin that is relying on this being present for a model. It has happened to all of us and is a royal pita)
Once attr_accessible is designated for a class, then any attribute that is not specified as 'accessible' will not be allowed to be updated.
Here is an example of my problem.
I have a 'Room' model:
class Room < ActiveRecord::Base
has_many :items, :inverse_of => :room
accepts_nested_attributes_for :items
end
And I have an 'Item' model:
class Item < ActiveRecord::Base
belongs_to :room, :inverse_of => :items
validates :some_attr, :uniqueness => { :scope => :room}
end
I want to validate the uniqueness of the :some_attr attribute of all the Items which belongs to a certain room.
When I try to validate the items, I get this error:
TypeError (Cannot visit Room)
I cannot set the scope of the validation to be :room_id since the items are not saved yet so the id is nil. I also want to prevent using custom validators in the 'Room' model.
Is there any clean way to do it in Rails? I also wonder if I set the :inverse_of option correctly...
I don't see anything wrong with how you're using inverse_of.
As for the problem, in a similar situation I ended up forcing a uniqueness constraint in a migration, like so
add_index :items, [ :room_id, :some_attr ], :unique => true
This is in addition to the AR-level validation
validates_uniqueness_of :some_attr, :scope => :room_id
(I'm not sure if it's valid to use the association name as a scope, won't the DB adapter raise an exception when trying to refer to the non-existent room column in a query?)
I recently upgraded an app to rails 3.2.2.
I'm using Factory_girl
Factory.sequence :name do |n| "name-#{n}" end
Factory.define :user do |u| u.first_name{ Factory.next(:name) }
u.last_name { |u| 'last_' + u.first_name } u.password 'secret'
u.password_confirmation { |u| u.password } u.sequence(:email) { |i|
"user_#{i}#example.com" }
end
and this simple test
specify { Factory.build(:user).should be_valid }
generate the following warning
DEPRECATION WARNING: You're trying to create an attribute user_id'.
Writing arbitrary attributes on a model is deprecated. Please just use
attr_writer` etc. (called from block (2 levels) in
at...
How can I get rid of it?
It's probably because you haven't prepared/migrated your test database with updated column definitions, thus it thinks you're trying to arbitrarily set the attribute.
Run rake db:test:prepare to make sure it's updated.
Here's the source code of that method, where you can see Rails checks for the column or attribute first, then warns if they're not found.
I've met the same warning with the following code:
Ad model:
class Ad < ActiveRecord::Base
belongs_to :user
end
Factories:
FactoryGirl.define do
factory :ad do
association :user
end
end
FactoryGirl.define do
factory :user do
first_name {Factory.next(:first_name)}
last_name {Factory.next(:last_name)}
email {|x| "#{x.first_name}.#{x.last_name}#{Factory.next(:count)}#test.com"}
password Forgery(:basic).password
confirmed_at Date.today << 10
end
end
Test
require 'spec_helper'
describe Ad do
before(:each) do
#ad = Factory.build(:ad)
end
"it is not valid without a user"
end
Running the test gave me a similar error.
Adding
attr_accessor :user
to the Ad model fixed the warning.
I hope it helps.
I had this same warning while doing tests in Rspec and my issue was that I had a Parent model and Child model where I accidentally had this:
class Child < ActiveRecord::Base
belongs_to :parent
end
......
class Parent < ActiveRecord::Base
belongs_to :child
end
I'm working on an app that has the models User and Project, and User can be assigned to multiple Projects, via ProjectUser, with a role (e.g. Developer, Designer).
Project
has_many :project_users
has_many :users, :through => :project_users
User
has_many :project_users
has_many :projects, :through => :project_users
ProjectUser (user_id, project_id, role)
belongs_to :user
belongs_to :project
I can call #project.users and #user.projects, but since there are varying roles, I'd like to be a bit more specific with the relations. Ideally, I want to be able to do the following:
#project.developers
# returns #project.users, but only where ProjectUser.role = 'Developer'
#project.designers << #user
# creates a ProjectUser for #project, #user with role 'Designer'
#user.development_projects
# returns projects where #user is assigned as a 'Developer'
#user.design_projects << #project
# creates a ProjectUser for #project, #user with role 'Designer'
I currently have the following code:
has_many :developers, :through => :project_users, :source => :user,
:class_name => "User",
:conditions => ['project_users.role = ?','Developer']
But this only really does the fetching one-way, and doesn't give me much else - I can't build or assign or anything.
I'm attempting some more complex logic which I think might work, but would appreciate some pointers:
has_many :developer_assignments, :source => :project_user,
:conditions => { :role => 'Developer' }
has_many :developers, :through => :developer_assignments # class_name?
Any suggestions? Thanks!
has_many accepts a block that can define/override methods for the association. This will allow you to create a custom method for <<. I've created a small example for you, you could create build in a similar fashion.
# Project.rb
has_many :developers, :through => :project_users, :source => :user,
:conditions => "project_users.role = 'developer'" do
def <<(developer)
proxy_owner.project_users.create(:role => 'developer', :user => developer)
end
end
Now you can add a new developer to your your project with: #project.developers << #user as requested. #project.developers gives you all the developers.
If you have a lot of roles, it might be useful to create these has_many statements dynamically.
# Project.rb
ROLES = ['developer','contractor']
ROLES.each do |role|
self.class_eval <<-eos
has_many :#{role.downcase}s, :through => :project_users, :source => :user,
:conditions => "project_users.role = '#{role}'" do
def <<(user)
proxy_owner.project_users.create(:role => '#{role}', :user => user)
end
end
eos
end
Looking back at everything above it doesn't seem like the rails way of doing things. Scoping this should make it possible to get the build and create commands working without redefining everything.
Hope this helps!
It sounds like what you're looking for is a combination of RoR's single table inheritance and named scopes.
Take a look at the following article for a nice example about polymorphic associations. This should help you with achieving the following:
#project.developers
# returns #project.users, but only where ProjectUser.role = 'Developer'
#project.designers << #user
# creates a ProjectUser for #project, #user with role 'Designer'
Scopes will give you a clean way to implement #user.development_projects but there may be more trickery required to get the << operator.
Did you try using scopes yet? It doesn't let you do <<. But it simplifies querying.
Try:
Project
scope :developers, lambda {
includes(:project_users).where("project_users.role = ?", "developer")
}
You will be able to get all developers using: #project.developers