I have come across a bit of confusion regarding the use of view helpers controllers. The kind of scenario I have is:
session_helper.rb:
module SessionsHelper
# logs in the given user.
def log_in(user)
session[:user_id]=user.id
end
sessions_controller.rb:
class SessionsController < ApplicationController
def create
user = User.find_by(email: params[:session][:email].downcase)
if user && user.authenticate(params[:session][:password])
log_in user
redirect_to user
end
end
def destroy
log_out
redirect_to root_url()
end
Now, as per the documentation that I have read, it mentions that helpers are used in views, to reduce the amount of coding to be done there.
My question is: how I am able to use the log_in and log_out methods defined in the session_helper in my controller?
If anyone can clear me on this concept would be very much helpful.
Answer on your question:
ActionController::Base.helpers.log_in(user)
But, it's better to place those methods in the controller.
Related
In my application I have permissions set up like so for an admin:
can :read, Journey
can :destroy, Journey
can :update, Journey
And I have controllers like so:
class JourneyController < ApplicationController
authorize_resource class: :journey
def index; end
def show; end
end
module Journeys
class VoidJourneyController < ApplicationController
authorize_resource class: :journey
def show; end
def destroy; end
end
end
This is based on how DHH does his controllers: http://jeromedalbert.com/how-dhh-organizes-his-rails-controllers/
Now the issue I have is that because I have a show method inside the VoidJourney controller (this is to show the user some additional information as we talk to an API) it means a user who doesn't have permission to destroy a journey can access it because show is aliased to read and only the destroy is protected in that controller.
CanCanCan has the alias_action method, but that only allows aliasing a method to another for all controllers, not just one.
The only way I could think to handle this was to do:
def show
authorize! :destroy, :journey
end
So that it checks that method against a different permission. But I'd like to avoid having to do that if possible.
Is it possible to alias a method in only one controller to another? And not alias for all controllers. Looking at the docs I can't see this.
I am working on a application where Users can list their in-game items to trade with other Users. A user's profile url would be something like this:
/users/1/index
And their user listings profile would be something like
/users/1/listings/1
All other resources nested under users would be the same as the latter.
I am trying to implement a method that is called by a before_filter callback that checks to see if a user has blocked or is blocked by the user who owns the profile and respective nested resources such as ability to message them, view their listings etc. If either has blocked each other, then they redirected to the root page of the application. This is the method that I use for the before_filter:
def blocked_relationships
if blocked?
redirect_to :root
end
end
I used another method that checks the state of the relationships between the two users.
This is the method I found and worked on after some research courtesy of the Rails Recipes book:
def blocked?
Relationship.exists?(user_id: current_user.id, other_user_id: params[:user_id], status: "blocked") ||
Relationship.exists?(user_id: params[:user_id], other_user_id: current_user.id, status: "blocked")
end
The problem I have is that this method only works, for example, when User 1 is looking at User 2's items, messages, listings etc. because the url:
/users/2/listings [or items or etc]
will contain a params that makes reference to the user as params[:user_id]. params[:id] in this case and context will refer to the listings id.
BUT, if I am User 1 and I have blocked User 2 and visit User 2's profile, this method will not work because the url /users/2/index will use params[:id] to instead of params[:user_id].
I've been thinking about how to implement this in a DRY way but I can't seem to solve my problem other than doing something like this:
def blocked?
if params[:user_id].blank?
Relationship.exists?(user_id: current_user.id, other_user_id: params[:id], status: "blocked") ||
Relationship.exists?(user_id: params[:id], other_user_id: current_user.id, status: "blocked")
else
Relationship.exists?(user_id: current_user.id, other_user_id: params[:user_id], status: "blocked") ||
Relationship.exists?(user_id: params[:user_id], other_user_id: current_user.id, status: "blocked")
end
end
I also considered the possibility that I'm not even implementing my blocking feature correctly, but before I address that issue, I was wondering if anyone had any ideas on how to solve this problem. Any help or feedback would be greatly appreciated and I would be happy to add anymore information for clarification. Thanks!
Why not other_id = params[:user_id] || params[:id]? This is a way to override :id when :user_id is present.
About your blocking feature though, to me I'd like to see a user even if I've blocked them. I'd create a blocked_by_user_id field on the Relationship to see who did the blocking and only disallow the blocked party from seeing the user's profile.
You'd probably want to checkout authorization gems for rails like cancan or related (it's not my favorite but the most popular). However, you could handle it like this:
class User
has_many :relationships,
scope :accessible_by,
->(user) { where.not id: user.relationships.where(status: :blocked).pluck(:other_user_id) }
end
Then use the relationship User.accessible_by(current_user) on your controller instead of plainly User to retrieve resources. For example:
class UsersController < ApplicationController
def index
#users = User.accessible_by(current_user)
# bleh
end
def show
#user = User.accessible_by(current_user).find(params[:id])
# etc
end
end
When the resource is nested under a user you could do this:
class Users::PicturesController < UsersController
def index
#pictures = User.accessible_by(current_user)
.find(params[:user_id]).pictures
end
def show
#picture = User.accessible_by(current_user)
.find(params[:user_id]).pictures.find(params[:id])
end
end
When a user tries to access a resource that can't view, ActiveRecord::RecordNotFound will be raised, so you should handle it:
class ApplicationController < ActionController::Base
rescue_from ActiveRecord::RecordNorFound, with: :rescue_not_found
private
def rescue_not_found
redirect_to root_path,
notice: 'You can\'t access that with your current priveleges. '
end
end
I am learning Ruby on Rails and was looking into utilizing cancan to help restrict users access to actions that they shouldn't have and to pages depending on who they are. I currently understand how to restrict actions, but I was curious if someone could help with actually restricting certain pages and unique pages.
One example is I have a home page for admin users and one for regular users, how would I restrict the admin page from the normal user?
Thanks, and any pointers on if I am doing something wrong is greatly appreciated.
If you want to use cancan :
Admit you add in your user controller a method admin_home :
def admin_home
#user = current_user
authorize! :admin_home
end
You need to specify in ability.rb file you want to restrict access to admin_home for standard users :
class Ability
include CanCan::Ability
def initialize(user)
user ||= User.new # guest user (not logged in)
if user.admin?
#Authorize all actions
can :manage, User
else
#authorize only self modifications and restrict access to admin_home
can :manage, User, :id => user.id
cannot :admin_home, User
end
end
end
You can find great resources about cancan in official wiki like
https://github.com/ryanb/cancan/wiki/Defining-Abilities and
https://github.com/ryanb/cancan/wiki/Authorizing-controller-actions
Hope this help
Note: I am just giving you an example, you are not supposed to use it as it is, but you can have an Idea that how you will be able to put your logic.
class AdminsController < ApplicationController
before_filter :check_admin, :only => [:index, :show]
def index
#admins = //whatever your query for this action
end
def show
#admin = //whatever your query for this action
end
protected
def check_admin
if(my_condition to check if user type is admin)
{
return true // or anything u want for ur admin user
}
else
{
//anything here when user is not admin
1. you can redirect to users home page using redirect_to
2. you can redirect to a specific page which shows "You are not authorized to see this web page"
}
end
end
end
I've been trying Padrino framework in one of my project, and there is one thing that really annoys me. I want to implement just for instance a user registration process using OmniAuth and want to break my request handler (controller's action) to separate methods, like this:
get ":provider/callback" do
#user = find_the_user_by_oauth(request)
create_user unless #user
store_user_in_session
end
def find_the_user_by_oauth(request)
#...
end
def store_user_in_session
session[:user_id] = #user.id
end
I know it would be nicer to push the logic to the model layer, but my question is, how could I break a controller logic to separated methods and share information among them (like using instance variables). In Rails I created these methods in the private scope of my controller, but here I should extend the Application class because it throws Undefined method exception for the previous code. I tried Helpers, but helpers don't know the instance variables, so you should pass the variables every time.
What is the good way to make my controller actions clean in Padrino?
To define a method inside an Padrino Controller you can use define_method instead of def.
For your example, do something like this:
Admin.controllers :dummy do
define_method :find_the_user_by_oauth do |request|
request.params["username"]
# ...
end
define_method :store_user_in_session do
session[:user_id] = #user
end
get :test do
#user = find_the_user_by_oauth(request)
create_user unless #user
store_user_in_session()
session.inspect
end
end
Padrino runs the block sent to Admin.controllers using instance_eval.
See this answer for the differences https://stackoverflow.com/a/3171649 between define_method and def
possible offtopic, but would you consider to use Espresso Framework instead.
then you'll can solve your issue as simple as:
class App < E
def index provider, action = 'callback'
#user = find_the_user_by_oauth
create_user unless #user
store_user_in_session
end
private
def find_the_user_by_oauth
# provider, action are accessed via `action_params`
# action_params[:provider]
# action_params[:action]
end
def store_user_in_session
session[:user_id] = #user.id
end
end
I want to override authenticate_user! and current_user method of devise gem in my application Controller can you please help me with regards to that
Thanks
You may be able to monkey-patch it like:
module Devise
module Controllers
module Helpers
def authenticate_user!
#do some stuff
end
end
end
end
But I would ask what the ultimate goal is, because Devise has some customizability built into it already, and overriding these methods makes me wonder "why use Devise at all?"
On overriding how a user is authenticated:
Devise uses Warden under the hood
https://github.com/plataformatec/devise/blob/master/lib/devise/controllers/helpers.rb
So you can just add a new strategy in Warden to authenticate your users. See
https://github.com/hassox/warden/wiki/Strategies
You should not need to override current_user. What challenge are you facing ?
Do you need a different model returned ?
If you want to add code to authenticate_user!
class DuckController < ApplicationController
before_action :authenticate_duck
...
private
def authenticate_duck
#use Devise's method
authenticate_user!
#add your own stuff
unless current_user.duck.approved?
flash[:alert] = "Your duck is still pending. Please contact support for support."
redirect_to :back
end
end
end
You have to create a custom class to override the default Devise behavior:
class CustomFailure < Devise::FailureApp
def redirect_url
#return super unless [:worker, :employer, :user].include?(scope) #make it specific to a scope
new_user_session_url(:subdomain => 'secure')
end
# You need to override respond to eliminate recall
def respond
if http_auth?
http_auth
else
redirect
end
end
end
And in your config/initializers/devise.rb:
config.warden do |manager|
manager.failure_app = CustomFailure
end
But I suggest check out the Devise documentation :)
https://github.com/plataformatec/devise/wiki/How-To:-Redirect-to-a-specific-page-when-the-user-can-not-be-authenticated
At application_controller.rb you can overwrite just as you want:
def authenticate_user!
super # just if want the default behavior
call_a_method_to_something if current_user
# or
call_a_method_to_something if current_user.nil?
end