User has_many microposts Micropost belongs to users
take users who have more than 10 microposts
Controller:
def active_users
#users = User.active_users
end
Model
def self.active_users
self.select { |u| u.microposts.size > 10}
end
how to rewrite method active_users to ActiveRecord request (probably with using :count :group methods)
**UPDATE**
the solution
self.joins(:microposts).group("users.id").having("count(*) > 10").all
Counter_Cache is your answer.
Go for this maybe:
http://railscasts.com/episodes/23-counter-cache-column
http://guides.rubyonrails.org/association_basics.html#counter-cache
User has_many microposts
Micropost
belongs to users
counter_cache: true
Then do a migration:
class AddMicropostCountToUsers < ActiveRecord::Migration
def change
add_column :users, :microposts_count, :integer
end
end
Then you can go for something like.
#users = User.where('microposts_count > ?', 10)
For further customization, check the links.
Related
I am using cancan to authorize my controller actions. One of classes where access is authorized by cancan is a tree, implemented with acts_as_ancestry. I'm having problems using load_and_authorize_resource when the user is not permitted to access the root level, but rather is allowed access starting at an interior node.
Here are some relavant class definitions:
class User < ActiveRecord::Base
belongs_to :organization, :inverse_of => :users
end
class Post < ActiveRecord::Base
belongs_to :organization, :inverse_of => :posts
end
class Organization < ActiveRecord::Base
has_ancestry :cache_depth => true
has_many :users, :inverse_of => :organization
has_many :posts, :inverse_of => :organization
end
The rules for managing posts are "You can manage posts in any organization below yours". My cancan abilities definition is this:
class Ability
include CanCan::Ability
def initialize(user)
user ||= User.new
# subtree_ids is added by acts_as_ancestry
can :manage, Post, {:organization_id => user.organization.subtree_ids}
end
end
In the controller, I have this (other actions omitted)
class PostsController < ApplicationController
load_and_authorize_resource :post
def index
end
def new
end
end
Everything works fine when the authorized user belongs to the root organization. However, when I login as a user authorized at an internal node, the index action works fine, but when the new action is invoked, I get a can-can authorization error.
Here is what I see in the log:
Access denied on new #<Post id: nil, organization_id: 1>
The organization_id 1 (the root) is coming from the schema:
create_table "posts", :force => true do |t|
t.integer "organization_id", :default => 1
end
With cancan, the new action will build a new Post and assign it to #post. When it does this, it will initialize all the attributes with values taken from the can definition in Abilities.rb. However, it will not do anything if those attributes are Arrays, Hashes or Ranges and the default value ends up coming from the schema.
How can I authorize users to manage posts in their subtree, but when they create a new post, default it to their organization?
In cancan, if the #post variable is already initialized by you, it will not call load_resource on it, only do the authorize part. See this part of the docs: https://github.com/ryanb/cancan/wiki/Authorizing-controller-actions, "Override loading".
So the simplest solution is to take control of the initialization yourself and make it what you need, like here:
class PostsController < ApplicationController
before_filter :initialize_post, :only => [:new, :create]
def initialize_post
#post = current_user.organization.posts.build(params[:post]||{:name=>'Smashing Kittens'})
end
load_and_authorize_resource :post
def index
end
def new
end
def create
end
end
You can see it working in this test project that I created from your post: https://github.com/robmathews/cancan_test.
I had a similar issue and ended up writing ancestry related permissions in blocks like so:
can :manage, Post do |post|
post.organization.subtree_ids.include?(user.organization_id)
end
I am currently building very simple Comment system on Rails. The primary models are User, Albumpost, and Comment. Users can post Albumposts. For each Albumpost, Users can add Comments to the Albumpost. As a result, a Comment belongs to a User and belongs to an Albumpost.
The problem I'm having is that even with the proper associations in my models (see below), I can't get
#comment.user.name
when I'm trying to render the comments in the albumpost 'show' page (/views/albumposts/show.html.erb). When I go to the page, I can't get #comment.user.name (doesn't understand the association) and get a
"undefined method `name' for nil:NilClass"
Oddly I can get
#comment.albumpost.content
I've double-checked my models and also added the proper foreign keys to the models. Am I doing something wrong in the controllers?
Here are my models:
class Comment < ActiveRecord::Base
attr_accessible :body, :albumpost_id, :user_id
belongs_to :albumpost
belongs_to :user
end
class Albumpost < ActiveRecord::Base
attr_accessible :content
belongs_to :user
has_many :comments, dependent: :destroy
end
class User < ActiveRecord::Base
attr_accessible :name, :email, :password, :password_confirmation
has_many :albumposts, dependent: :destroy
has_many :comments, dependent: :destroy
end
Here are the relevant parts of my Albumpost and Comments controllers:
class AlbumpostsController < ApplicationController
def show
#albumpost = Albumpost.find(params[:id])
#comments = #albumpost.comments
#comment = Comment.new
#comment.albumpost_id = #albumpost.id
#comment.user_id = current_user.id
end
end
class CommentsController < ApplicationController
def create
albumpost_id = params[:comment].delete(:albumpost_id)
#comment = Comment.new(params[:comment])
#comment.albumpost_id = albumpost_id
#comment.user_id = current_user.id
#comment.save
redirect_to albumpost_path(#comment.albumpost)
end
end
I think you should prefer setting objects to relations instead of setting their ids. For example, you should do this:
#comment.user = current_user
instead of
#comment.user_id = current_user.id
ActiveRecord will take care of setting corresponding *_id fields. I'm not sure how it handles the reverse. (it should autoload though, if I understand correctly)
I have a model called DefaultCompany that has no controller, instead I create it through the companies_controller which calls the user.set_default_company (defined below) if they check the "default company" checkbox on the form.
Default company is a joining table of user_id and company_id.
class DefaultCompany < ActiveRecord::Base
attr_accessible :company_id, :user_id
belongs_to :company
belongs_to :user
end
I keep getting the following error:
Can't mass-assign protected attributes: company, user
app/models/user.rb:22:in `set_default_company'
app/controllers/companies_controller.rb:23:in `create'
I've set my user model to be able to accept nested attributes for DefaultCompany, like this
class User < ActiveRecord::Base
has_one :default_company
accepts_nested_attributes_for :default_company
attr_accessible :default_company_attributes
def set_default_company(company)
exists = DefaultCompany.find(self.id)
if exists
exists.update_attributes(company: company)
else
DefaultCompany.create(company: company, user: self)
end
end
end
And here is the create action for the companies_controller.rb
def create
#company = Company.new(params[:company])
if #company.save
if params[:default_company]
current_user.set_default_company #company.id
end
flash[:notice] = "Company was successfully created."
Role.assign_creator(#company.id, current_user.id)
redirect_to #company
else
redirect_to new_company_path
end
end
So I'm not sure what I need to add so that mass-assignment will pass, can anyone help me figure out / explain this?
I believe rails is strict about the naming in mass-assignment, so although you've whitelisted company_id and user_id, you have not whitelisted company and user.
Try changing the assignment in set_default_company to:
if exists
exists.update_attributes(company_id: company.id)
else
DefaultCompany.create(company_id: company.id, user_id: self.id)
end
You can either change the attr_accessible attributes on Company to :user and :company or set :company_id and :user_id in your set_default_company method call.
Edit:
exists = DefaultCompany.find(self.id)
This seems to be wrong according to your logic.
I have a model named User . I am using Devise for authentication.
The 'User' has many 'Profiles' and one default profile . So I have added a column called 'default' to the User model. I want to store the id of the default profile.
However the code fails at the current_user.default = statement.
Error - undefined method `default=' for #User:0x402c480
class User < ActiveRecord::Base
..........
has_many :profiles
...........
# Setup accessible (or protected) attributes for your model
attr_accessible :email, :password, :password_confirmation, :remember_me, :default
end
.......
class ProfilesController < ApplicationController
before_filter :authenticate_user! ,:except => [:show]
def create
#profile = current_user.profiles.new(params[:profile])
#profile.user = current_user
respond_to do |format|
if #profile.save
#current_user.default= #profile.id
............
end
How do I go about this ? Adding 'default' to the User model doesnt solve the problem.
I suggest you to use STI, it means add "type" column into 'profiles' table
class User < ActiveRecord::Base
has_many :profiles
has_one :profile_default
after_create do
create_profile_default
end
end
class Profile < ActiveRecord::Base
end
class ProfileDefault < Profile
end
def create
#profile = current_user.profiles.new(params[:profile])
#profile.user = current_user
respond_to do |format|
if #profile.save
...
end
I've been following this guide on the Separate Role Model implementation in CanCan. When a User, tries to sign up this error is thrown when creating the Assignment.
User(#21477600) expected, got Symbol(#5785720)
I'm using a Devise generated User with the following before_save functions
class User < ActiveRecord::Base
.
.
.
def create_profile
profile = Profile.new :user_id => :id
end
def create_role
Assignment.new :user => :id, :role => Role.find_by_role("user").id
end
end
I want to default the user's role to "user", but I'm obviously doing something wrong. How should this be implemented?
Not sure if you've seen this or not, but Ryan Bates has produced a wonderful document regarding:
Separate Role Models
EDIT:
Here's what I am currently using. I believe your 'Assignment' is the same as my 'UserRole'.
user.rb
#--
# Relationship
has_many :user_roles, :dependent => :destroy, :uniq => true
has_many :roles, :through => :user_roles, :uniq => true
#--
# Instance Method
# Determine if the user has a specified role
# You can find this method at: https://github.com/ryanb/cancan/wiki/Separate-Role-Model
# Written by Ryan Bates, I added the downcase though to detect 'Admin' vs 'admin'.
# Example:
# user.has_role? :Admin
# => true
def has_role?(role_sym)
roles.any? { |role| role.name.underscore.to_sym == role_sym.downcase }
end
role.rb
# id :integer(4) not null, primary key
# name :string(255)
#--
# Relationship
has_many :user_roles, :dependent => :destroy, :uniq => true
has_many :users, :through => :user_roles, :uniq => true
user_role.rb
# id :integer(4) not null, primary key
# user_id :integer(4)
# role_id :integer(4)
#--
# Relationship
belongs_to :user
belongs_to :role
Then in my ability.rb
def initialize(user)
user ||= User.new # in case of a guest
if user.has_role? :Admin # The user is an Administrator
can :manage, :all
else
can :read, :all
end
end
Then I can easily assign roles, like in my seed file by doing something like:
# Create Users
...
# Roles
admin = Role.create!(:name => "admin")
standard = Role.create!(:name => "standard")
# UserRoles :Admin
user1.roles << admin
user2.roles << standard
So by calling user.roles << [role_name], I am essentially creating a UserRole, which has a user_id and a role_id.
There might be some more effective ways to accomplish this, but I cant tell without the exact model associations.
Anyway, I think this should work:
def create_role
Assignment.new :user => self, :role => Role.find_by_role("user")
end
Since you specify :user and not :user_id, you should pass self. The same thing for :role. If you had specified :role_id then you should have entered .id after find_by_role but since you only specify :role then remove .id
It looks like you're passing symbols to hash conditions that are expecting objects.
DanneManne's answer should work. You could alternatively do
Assignment.new( :user_id=>self.id, :role_id => Role.find_by_role('user').id )
(but Danne's is better, imo)
One last suggestion -- why not say the name of the role is "name", not "role". So then you'd be doing, Role.find_by_name('user'). That would be easier for a subsequent programmer to follow.
Firstly, you should not use save callback because it will be fired on both create & update.
Secondly, if you set up associations between models like that:
class User < ActiveRecord::Base
has_one :profile
has_many :assignments
end
class Profile < ActiveRecord::Base
belongs_to :user
end
class Assignment < ActiveRecord::Base
belongs_to :user
belongs_to :role
end
You will have convenient methods like user.profile, user.build_profile and user.create_profile. Build & create will set up user_id on profile automatically. You can use them in your callbacks without having to define any methods.
Note that before user is saved it does not have an id. So you need to use either before_create :build_profile either after_create :create_profile. The first one will create profile in memory that will be autosaved after user is saved, the second one is pretty straightforward.
There will be similar methods for assignments too: user.assignments.build user.assignments.create. So the final code for User will look something like this
class User < ActiveRecord::Base
has_one :profile
has_many :assignments
after_create :create_profile, :create_assignment
def create_assignment
assignments.create :role => Role.find_by_role("user")
end
end