Devise with Associated Record validation - ruby-on-rails

My background
I am/was a PHP developper. Have been for 15 years. Ruby is new to me (My new challenge)!
Current Setup
I am using Devise with a User model.
Rails: 3.2.1
Devise: 2.1.2
Use Case
When the user registers (going thru Devise controller), I want to create the User record but also a Foo record automatically. I created an after_create which handles the creation of the Foo record.
Class User < ActiveRecord::Base
after_create :make_foo
def make_foo
Foo.create(
:name => name,
:user_id => id
)
end
end
Class Foo < ActiveRecord::Base
belongs_to :user
end
Symptoms
I had a problem where when the Foo record was not being created (validation for example), then the User record was still created (I did not want that). I added a Raise Exception in after_create which rolls back the User creation.
However, I would prefer some nice error handling rather than Exception being throwed. Right now I get a 500 Error page with that Exception.
I would prefer that the form can be shown again with the reason(s) of the failure.
Class User < ActiveRecord::Base
after_create :make_foo
def make_foo
foo = Foo.create(
:name => name,
:user_id => id
)
if !foo.valid?
raise Exception.new('Foo creation failed.')
end
end
end
Plea for help
Any suggestions?

Instead of raising an exception you can redirect back to same page with setting flash message in
if !foo.valid?
block like this
flash[:error] = 'error msg'
and redirect using
session[:return_to] = request.referer
redirect_to session[:return_to]

I ended up overriding the Devise Resitrations Controller and putting a begin...rescue...end inside the create method.
# routes.rb
devise_for :users, :controllers => { :registrations => "my_devise/registrations" }
# app/controllers/my_devise/registrations_controller.rb
class MyDevise::RegistrationsController < Devise::RegistrationsController
def create
begin
super
rescue Exception
self.resource.errors[:base] << "My error message here"
clean_up_passwords resource
respond_with resource
end
end
end

You might want to look at Rails3: Devise User has_one relationship to see if better modelling can make the problem easier.
The way you are modelling user.rb now, is indeed such that a User may exist without Foo (which must belong to a User however), so it just calls :make_foo as an after_create callback with no other guarantees whatsoever.

Related

Creating model and nested model (1:n) at once with ActiveRecord

My Rails5 application has an organization model and a user model (1:n relationship). The workflow of creating an organization should include the creation of the organization's first user as well. I thought this would be able with ActiveRecord through nested models, however the create action fails with the error message "Users organization must exist".
class Organization < ApplicationRecord
has_many :users, dependent: :destroy
accepts_nested_attributes_for :users
end
class User < ApplicationRecord
belongs_to :organization
end
class OrganizationsController < ApplicationController
def new
#organization = Organization.new
#organization.users.build
end
def create
#organization = Organization.new(organization_params)
if #organization.save
redirect_to #organization
else
render 'new'
end
end
def organization_params
params.require(:organization).permit(:name, users_attributes: [:name, :email, :password, :password_confirmation])
end
end
In the view I use the <%= f.fields_for :users do |user_form| %> helper.
Is this a bug on my side, or isn't this supported by ActiveRecord at all? Couldn't find anything about it in the rails guides. After all, this should be (theoretically) possible: First do the INSERT for the organization, then the INSERT of the user (the order matters, to know the id of the organization for the foreign key of the user).
As described in https://github.com/rails/rails/issues/18233, Rails5 requires integrity checks. Because I didn't like a wishy-washy solution like disabling the integrity checks, I followed DHH's advice from the issue linked above:
I like aggregation through regular Ruby objects. For example, we have a Signup model that's just a Ruby object orchestrating the build process. So I'd give that a go!
I wrote a ruby class called Signup which encapsulates the organization and user model and offers a save/create interface like an ActiveRecord model would. Furthermore, by including ActiveModel::Model, useful stuff comes in to the class for free (attribute hash constructor etc., see http://guides.rubyonrails.org/active_model_basics.html#model).
# The Signup model encapsulates an organization and a user model.
# It's used in the signup process and helps persisting a new organization
# and a referenced user (the owner of the organization).
class Signup
include ActiveModel::Model
attr_accessor :organization_name, :user_name, :user_email, :user_password, :user_password_confirmation
# A save method that acts like ActiveRecord's save method.
def save
#organization = build_organization
return false unless #organization.save
#user = build_user
#user.save
end
# Checks validity of the model.
def valid?
#organization = build_organization
#user = build_user
#organization.valid? and #user.valid?
end
# A create method that acts like ActiveRecord's create method.
# This builds the object from an attributes hash and saves it.
def self.create(attributes = {})
signup = Signup.new(attributes)
signup.save
end
private
# Build an organization object from the attributes.
def build_organization
#organization = Organization.new(name: #organization_name)
end
# Build a user object from the attributes. For integritiy reasons,
# a organization object must already exist.
def build_user
#user = User.new(name: #user_name, email: #user_email, password: #user_password, password_confirmation: #user_password_confirmation, organization: #organization)
end
end
Special thanks to #engineersmnky for pointing me to the corresponding github issue.
You're looking for "Association Callbacks". Once you send those params to your organization model you have access to them inside that model. If everytime an organization is created there will be a new user assigned to it you can just do the following in your Organization Model:
has_many :users, dependent: :destroy, after_add: :create_orgs_first_user
attr_accessor: :username #create virtual atts for all the user params and then assign them as if they were organizational attributes in the controller. This means changing your `organization_params` method to not nest user attributes inside the array `users_attributes`
def create_orgs_first_user
User.create(name: self.username, organization_id: self.id, etc.) # You can probably do self.users.create(params here) but I didn't try it that way.
end
The "Users organization must exist" error should not occur. ActiveRecord is "smart," in that it should execute two INSERTs. First, it will save the model on the has_many side, so that it has an id, and then it will save the model on the belongs_to side, populating the foreign key value. The problem is actually caused by a bug in accepts_nested_attributes_for in Rails 5 versions prior to 5.1.1. See https://github.com/rails/rails/issues/25198 and Trouble with accepts_nested_attributes_for in Rails 5.0.0.beta3, -api option.
The solution is to use the inverse_of: option or, better yet, upgrade to Rails 5.1.1.
You can prove that this is true by removing the accepts_nested_attributes_for in your Organization model and, in the Rails console, creating a new Organization model and a new User model, associating them (eg myorg.users << myuser) and trying a save (eg myorg.save). You'll find that it will work as expected.

Best name for a Rails controller?

I'm writing a simple Rails app and I'm wondering what to name a controller that creates accounts.
Some background: Users create a schedule and it's publicly visible. There are users and events. An event can have multiple event_sessions. That's pretty much it.
During registration a user is created, an event is created, and sessions are created. So where do I put this, the UsersController? And, if account creation includes all this other stuff, do I put it in a new controller? If so, what do I call the controller — ExternalSiteController? AccountController?
I would start with something like the following, and tweak as necessary:
class UsersController < ActionController::Base
def create
# ...
User.create(user_params)
# ...
end
end
class User < ActiveRecord::Base
after_create :setup_initial_event
has_many :events
DEFAULT_EVENT_PARAMS = {
# ...
}
def setup_initial_event
events.create(DEFAULT_EVENT_PARAMS)
end
end
class Event < ActiveRecord::Base
after_create :setup_initial_sessions
belongs_to :user
has_many :sessions
def setup_initial_sessions
# You get the idea
end
end
If you don't have an account model (in which case AccountsController would be perfect), I'd put the code in the UsersController. User is probably the most complex and important model of the three (the registration of a user is what's kicking everything off, after all). Of course, you can create any object in any controller (i.e. you can call User.create() in the EventsController).

Devise remove a user but keep his data, and set a flag _is_deleted in rails 3.1

I would like to delete a user with devise but be able to save its data just setting a flag like is_deleted to true and prevent login for those users.
What would be the best way to do this in devise ? I have seen some write-ups on this but they were for rails 2.x projects, Im on rails 3.1
If you want to prevent sign_in users whose deleted_at fields are not null, override active_for_authentication? on your devise resource model:
def active_for_authentication?
super && !deleted_at
end
You can set that deleted flag normally then override the find_for_authentication class level method in the user model.
The following should work
def self.find_for_authentication(conditions)
super(conditions.merge(:is_deleted => false))
end
Another approach is to use a default scope on your model.
Define a state on your User model, and add a default scope (Rails 3), this will scope all the queries on the User model with the condition from the scope:
app/models/user.rb
class User < ActiveRecord::Base
default_scope where("state != 'disabled'")
def disable!
self.update_attribute(:state, 'disabled')
end
end
Then, over-write the destroy method in your session controller, make sure you to grab the destroy code from the version of devise you're using:
*app/controllers/registrations_controller.rb*
class Users::RegistrationsController < Devise::RegistrationsController
# paranoid DELETE /resource
def destroy
resource.disable! # we don't remove the record with resource.destroy
Devise.sign_out_all_scopes ? sign_out : sign_out(resource_name)
set_flash_message :notice, :destroyed if is_navigational_format?
respond_with_navigational(resource){ redirect_to after_sign_out_path_for(resource_name) }
end
end
You can take it a step further by defining a state machine on your User model (be careful of how this will not cascade down the dependency tree, like a :dependent => :destroy would):
app/models/user.rb
class User < ActiveRecord::Base
include ActiveRecord::Transitions
state_machine do
state :passive
state :active
state :disabled, :enter => :bye_bye_user
event :activate do
transitions :from => :passive, :to => :active
end
event :disable do
transitions :from => [:passive,:active], :to => :disabled
end
end
default_scope where("state != 'disabled'")
end
#dgmdan: In regards to using :deleted_at => nil instead of false:
Devise's find_for_authentication method runs the conditions through a filter which stringifies values. What's happening is that the nil value being passed in for deleted_at is being converted to an empty string. This makes the query match no one, and thus to the end user it looks like the username and password were incorrect.
find_for_authentication calls find_first_by_auth_conditions like this:
def find_for_authentication(tainted_conditions)
find_first_by_auth_conditions(tainted_conditions)
end
Per the author, find_first_by_auth_conditions takes an optional second parameter, another conditions hash, but this one does not go through the filter. So what you can do is change the method like this:
def self.find_for_authentication(conditions)
find_first_by_auth_conditions(conditions, {:deleted_at => nil})
end
The second conditions hash with the :deleted_at => nil should be passed straight through to the ORM layer.

how to automatically add a role to a user when signing up using devise

I am using Devise 1.1.5. I got a roles and a roles_assignment table. Is it possible to assign a role automatically in my role_assignments table when the user signs up? Many thanks!
I tried this but it wont work
class User < ActiveRecord::Base
after_create :assign_role_after_sign_up
protected
def assign_role_after_sign_up(user)
RoleAssignment.create(:role_id => 1, :user_id => user.id)
end
end
Your after_create method won't work because you're trying to pass user, which isn't much of anything in the model. All user attributes are actually accessible as instance variable, so you should instead do:
def assign_role_after_sign_up
RoleAssignment.create(:role_id => 1, :user_id => id)
end
If you have a relationship between users and role_assignments (and if you don't, why not?), you can simply do this instead:
# If user :has_one :role_assignment
def assign_role_after_sign_up
create_role_assignment(:role_id => 1)
end
# If user :has_many :role_assignments
def assign_role_after_sign_up
role_assignments.create(:role_id => 1)
end
Create an after_create callback in the User model that creates and saves a role for the newly created user.
More information about callbacks is available in the Ruby on Rails guides.

How to test a named_scope that references a class attribute with Shoulda?

I have the following ActiveRecord classes:
class User < ActiveRecord::Base
cattr_accessor :current_user
has_many :batch_records
end
class BatchRecord < ActiveRecord::Base
belongs_to :user
named_scope :current_user, lambda {
{ :conditions => { :user_id => User.current_user && User.current_user.id } }
}
end
and I'm trying to test the named_scope :current_user using Shoulda but the following does not work.
class BatchRecordTest < ActiveSupport::TestCase
setup do
User.current_user = Factory(:user)
end
should_have_named_scope :current_user,
:conditions => { :assigned_to_id => User.current_user }
end
The reason it doesn't work is because the call to User.current_user in the should_have_named_scope method is being evaluated when the class is being defined and I'm change the value of current_user afterwards in the setup block when running the test.
Here is what I did come up with to test this named_scope:
class BatchRecordTest < ActiveSupport::TestCase
context "with User.current_user set" do
setup do
mock_user = flexmock('user', :id => 1)
flexmock(User).should_receive(:current_user).and_return(mock_user)
end
should_have_named_scope :current_user,
:conditions => { :assigned_to_id => 1 }
end
end
So how would you test this using Shoulda?
I think you are going about this the wrong way. Firstly, why do you need to use a named scope? Wont this just do?
class BatchRecord < ActiveRecord::Base
belongs_to :user
def current_user
self.user.class.current_user
end
end
In which case it would be trivial to test. BUT! WTF are you defining current_user as a class attribute? Now that Rails 2.2 is "threadsafe" what would happen if you were running your app in two seperate threads? One user would login, setting the current_user for ALL User instances. Now another user with admin privileges logs in and current_user is switched to their instance. When the first user goes to the next page he/she will have access to the other persons account with their admin privileges! Shock! Horror!
What I reccomend doing in this case is to either making a new controller method current_user which returns the current user's User instance. You can also go one step further and create a wrapper model like:
class CurrentUser
attr_reader :user, :session
def initialize(user, session)
#user, #session = user, session
end
def authenticated?
...
end
def method_missing(*args)
user.send(*args) if authenticated?
end
end
Oh, and by the way, now I look at your question again perhaps one of the reasons it isn't working is that the line User.current_user && User.current_user.id will return a boolean, rather than the Integer you want it to. EDIT I'm an idiot.
Named scope is really the absolutely wrong way of doing this. Named scope is meant to return collections, rather than individual records (which is another reason this fails). It is also making an unnecessary call the the DB resulting in a query that you don't need.
I just realized the answer is staring right at me. I should be working from the other side of the association which would be current_user.batch_records. Then I simply test the named_scope on the User model and everything is fine.
#Chris Lloyd - Regarding the thread safety issue, the current_user attribute is being set by a before_filter in my ApplicationController, so it is modified per request. I understand that there is still the potential for disaster if I chose to run in a multi-threaded environment (which is currently not the case). That solution I suppose would be another topic entirely.

Resources