Testing a Rails ApplicationController method with rspec - ruby-on-rails

Just having trouble figuring out how to test an action that utilizes a private ApplicationController method. To explain:
A User has and belongs to many Organisations (through Roles), and vice versa. An Organisation has a bunch of related entities, but in the app a user is only dealing with a single Organisation at a time, so for all of my controller methods I want to scope with a current organisation. So in my ApplicationController:
private
# Returns the organisation that is being operated on in this session.
def current_org
# Get the org id from the session. If it doesn't exist, or that org is no longer operable by the current user,
# find an appropriate one and return that.
if (!session[:current_organisation_id] || !current_user.organisations.where(['organisations.id = ?', session[:current_organisation_id]]).first)
# If an org doesn't exist for this user, all hope is lost, just go to the home page
redirect_to '/' if (!current_user.organisations.first)
# Otherwise set the session with the new org
session[:current_organisation_id] = current_user.organisations.first.id;
end
# Return the current org!
current_user.organisations.first
end
First things first, I don't know if this is the best way to scope. I'd love some elegant default_scope thing, but with the use of session variables this seems problematic. Anyway, the above let's me do this in controllers:
class HousesController < ApplicationController
def index
#houses = current_org.houses
end
end
So now I want to use rspec to test my controllers. How can I make sure the current_org method can be called and returns one of the factory_girl Organisation models so that I can write the spec. I'm just confused at how best to bring the factory, spec, action and AppControlled method together.

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Rails 6 - Pundit "policy wrapper"

I am a little stuck with Pundit: It feels that the solution should be easy - but I am not getting it. Actually I have a bunch of models which are all dependent on one main model. My main model is a script. The script has many roles, many scenes, many costumes, etc. Additionally it has some joined connections like scene.roles. I simply want to authorize the user who created the script to do everything (adding roles, deleting scenes, just everything that is in the scope of her own script) and everybody else to do (and see) nothing. Do I need to create a policy for every model or can I just (re-)use somehow one "script policy"?
How would an authorization look like in a dependent controller (i.e. 'index' in roles or 'new' in scenes)?
The authentication is handled by Device. A user must be logged in to see or do anything.
This is my first post on stack overflow, happy to join the community:-)
Pundit policies are POROs (plain old ruby objects). So you can easily create a policy for the main model:
class ScriptPolicy
attr_reader :user, :script
def initialize(user, script)
#user = user
#script = script
end
def update?
user.actor?
end
def delete?
user.admin?
end
end
And then for every model that you have, simply create an empty class definition that inherits from the ScriptPolicy
class ScenePolicy < ScriptPolicy
end
Another approach would be to overwrite the policy name that Pundit is referencing directly in the child model. So assuming that you have a model Scene that shall use the same policy as Script, you can add a method:
class Scene < ActiveRecord::Base
def self.policy_class
ScriptPolicy
end
end
In the latter, you do not need to create empty policy classes for every model, but you trade it for the decreased flexibility in defining specific permissions for models.
When calling the authorize method in your controller, you can specify the policy class:
authorize #model, policy_class: ScriptPolicy
I find that this solution generates less boilerplate files.
To authorize a scope:
scenes = policy_scope(Scene, policy_scope_class: ScriptPolicy::Scope)
By the way, this is all covered in pundit's README: https://github.com/varvet/pundit

Check object type in Rails controller before calling method

I'm wondering if there is a more object-oriented way to accomplish what I'm doing. A controller in my app has a 'vote' method, which allows a user to cast an up or down vote on a resource. In order for a resource to gain voting functionality, it has to include one of two modules: Votable or DistrictVotable.
The DistrictVotable module means that you need to specify a district when voting. With the Votable module, that is not the case, you can vote without a district.
So, here is what the relevant part of my controller method looks like:
def vote
#resource = find_resource
vote_type = params[:vote_type].to_i
if #resource.is_a? DistrictVotable
#resource.vote(district, vote_type, current_user)
elsif #resource.is_a? Votable
#resource.vote(vote_type, current_user)
end
end
To me, it seems less than ideal that the controller needs to check the #resource type before calling vote, but I can't figure out away around this since that determines whether or not a district needs to be passed in.
This vote method is added to the controller by a VotableController module. Maybe I need to create a separate DistrictVotableController so the type check won't be needed?
You could make the vote method accept arbitrary number of arguments. One way to do it is:
In Votable module:
def vote(args)
user = args.fetch(:user)
vote_type = args.fetch(:vote_type)
# some logic
end
In DistrictVotable module:
def vote(args)
user = args.fetch(:user)
vote_type = args.fetch(:vote_type)
district = args.fetch(:district)
# some logic
end
And you call it with
#resource.vote(user: current_user, vote_type: params[:vote_type], district: district)
The district parameter will be ignored in the Votable module.

Using current user in Rails in a model method

I'm currently trying to implement simple audit for users (just for destroy method). This way I know if the user has been deleted by an admin or user deleted itself. I wanted to add deleted_by_id column to my model.
I was thinking to use before_destroy, and to retrieve the user info like described in this post :
http://www.zorched.net/2007/05/29/making-session-data-available-to-models-in-ruby-on-rails/
module UserInfo
def current_user
Thread.current[:user]
end
def self.current_user=(user)
Thread.current[:user] = user
end
end
But this article is from 2007, I'm not sure will this work in multithreaded and is there something more up to date on this topic, has anyone done something like this lately to pass on the experience?
Using that technique would certainly work, but will violate the principle that wants the Model unaware of the controller state.
If you need to know who is responsible for a deletion, the correct approach is to pass such information as parameter.
Instead of using callbacks and threads (both represents unnecessary complexity in this case) simply define a new method in your model
class User
def delete_user(actor)
self.deleted_by_id = actor.id
# do what you need to do with the record
# such as .destroy or whatever
end
end
Then in your controller simply call
#user.delete_user(current_user)
This approach:
respects the MVC pattern
can be easily tested in isolation with minimal dependencies (it's a model method)
expose a custom API instead of coupling your app to ActiveRecord API
You can use paranoia gem to make soft deletes. And then I suggest destroying users through some kind of service. Check, really basic example below:
class UserDestroyService
def initialize(user, destroyer)
#user = user
#destroyer = destroyer
end
def perform
#user.deleted_by_id = #destroyer.id
#user.destroy
end
end
UserDestroyService.new(user, current_user).perform

Rails 3 ActiveRecord validation based on user permissions

I'm shifting code from an application built in a non-standard custom PHP framework into Ruby on Rails (version 3). In the PHP version all the controllers are really fat, with thin models, which I've always disagreed with, so I'm enjoying the way Rails does validation at the model level, which is probably 90% of what's happening in these fat controllers currently.
One problem I'm facing, and unsure how to resolve however, is that of differing validation rules based on who's making the change to the model. For example, an administrator, or the original creator of the record should be able to do things like flag a record as deleted (soft delete) whereas everybody else should not.
class Something < ActiveRecord::Base
...
validates :deleted, :owned_by_active_user => true
...
end
class OwnedByActiveUserValidator < ActiveModel::EachValidator
validate_each(record, attr_name, attr_value)
# Bad idea to have the model know about things such as sessions?
unless active_user.admin? || active_user.own?(record)
record.errors.add :base, "You do not have permission to delete this record"
end
end
end
Since the model itself is (in theory) unaware of the user who is making the change, what's the "rails way" to do this sort of thing? Should I set the active user as a virtual attribute on the record (not actually saved to DB), or should I just perform these checks in the controller? I have to admit, it does feel strange to have the model checking permissions on the active user, and it adds complexity when it comes to testing the model.
One reason I'm keen to keep as much of this as possible in the model, is because I want to provide both an API (accessed over OAuth) and a web site, without duplicating too much code, such as these types of permissions checks.
It is really the controller's job to handle authorization, or to delegate authorization to an authorization layer. The models should not know about, nor have to care about, who is currently logged in and what his/her permissions are - that's the job of the controller, or whatever auth helper layer the controller delegates that to.
You should make :deleted in-attr_accessible to mass assignment via new, create, or update_attributes. The controller should check the authenticated user's authorizations separately and call deleted= separately, if the authenticated user is authorized.
There are several authorization libraries and frameworks to help with authorization or to function as an authorization layer, such as cancan.
I would solve this with a before_filter in my controller, instead of with validations in my model.
class SomethingController < ApplicationController
before_filter :require_delete_permission, :only => [:destroy]
def destroy
# delete the record
end
private
def require_delete_permission
unless current_user.is_admin || record.owner == current_user
flash[:error] = 'You do not have delete permissions'
redirect_to somewhere
end
end
end
I have come across the same issue in Rails 2.3 and finally come up with this solution. In your model you define some atribute, depending on which you switch on/off validation. Than you your control you set this attribute depending on the date available to controller (such as user privileges in your case) as follows:
Class Model < ActiveRecord::Base
attr_accessor :perform_validation_of_field1 #This is an attribute which controller will use to turn on/off some validation logic depending on the current user
validates_presence_of :field1, :if => :perform_validation_of_field1
#This validation (or any similar one) will occur only if controller sets model.perform_validation_of_field1 to true.
end
Class MyController < ActionController::Base
def update
#item = Model.find(params[:id])
#item.update_attribute(params[:item])
#The controller decides whether to turn on optional validations depending on current user privileges (without the knowledge of internal implementation of this validation logic)
#item.perform_validation_of_field1 = true unless active_user.admin?
if #item.save
flash[:success] = 'The record has been saved'
redirect_to ...
else
flash.now[:error] = 'The record has not passed validation checks'
render :action => :edit
end
end
I think that in Rails 3 it can be done in similar manner.

Rails plugin for Group of users

My Rails application have a User model and a Group model, where User belongs to a Group. Thanks to this, a user can be a admin, a manager, a subscriber, etc.
Until recently, when for example a new admin need to be create on the app, the process is just to create a new normal account, and then an admin sets the new normal account's group_id attribute as the group id of the admin... using some condition in my User controller. But it's not very clean, I think. Because for security, I need to add this kind of code in (for example) User#update:
class UsersController < ApplicationController
# ...
def update
#user = User.find(params[:id])
# I need to add some lines here, just as on the bottom of the post.
# I think it's ugly... in my controller. But I can not put this
# control in the model, because of current_user is not accessible
# into User model, I think.
if #user.update_attributes(params[:user])
flash[:notice] = "yea"
redirect_to root_path
else
render :action => 'edit'
end
end
# ...
end
Is there a clean way to do it, with a Rails plugin? Or without...
By more clean, I think it could be better if those lines from User#update:
if current_user.try(:group).try(:level).to_i > #user.try(:group).try(:level).to_i
if Group.exists?(params[:user][:group_id].to_i)
if Group.find(params[:user][:group_id].to_i).level < current_user.group.level
#user.group.id = params[:user][:group_id]
end
end
end
...was removed from the controller and the application was able to set the group only if a the current user's group's level is better then the edited user. But maybe I'm wrong, maybe my code is yet perfect :)
Note: in my User model, there is this code:
class User < ActiveRecord::Base
belongs_to :group
attr_readonly :group_id
before_create :first_user
private
def first_user
self.group_id = Group.all.max {|a,b| a.level <=> b.level }.id unless User.exists?
end
end
Do you think it's a good way? Or do you process differently?
Thank you.
i prefer the controller methods to be lean and small, and to put actual model logic inside your model (where it belongs).
In your controller i would write something along the lines of
def update
#user = User.find(params[:id]
if #user.can_be_updated_by? current_user
#user.set_group params[:user][:group_id], current_user.group.level
end
# remove group_id from hash
params[:user].remove_key(:group_id)
if #user.update_attributes(params[:user])
... as before
end
and in your model you would have
def can_be_updated_by? (other_user)
other_user.try(:group).try(:level).to_i > self.try(:group).try(:level).to_i
end
def set_group(group_id, allowed_level)
group = Group.find(group_id.to_i)
self.group = group if group.present? && group.level < allowed_level
end
Does that help?
Well if you have a User/Groups (or User/Roles) model there is no other way to go than that you have underlined.
If it is a one-to-many association you can choose to store the user group as a string and if it is a many-to-many association you can go for a bitmask but nonetheless either through business logic or admin choice you need to set the User/Group relation.
You can have several choices on how to set this relationship in a view.
To expand your model's capability I advice you to use CanCan, a very good authorization gem which makes it super easy to allow fine grain access to each resource in your rails app.

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