Rails Admin Devise - How to edit other users?

Question

I have created a boolean on devise User to determine admins. Now that I have that, I have a list of Users. I want to make other users admins as well, so I put in Edit links, but they just keep linking to my own profile. Do I HAVE to use a gem like CanCan, or is there a way I can do this just with the boolean on a User?

admin_view.html.erb

 <div>
  <h1>Admin View</h1>
   <table>
    <thead>
     <tr>
      <th>First Name</th>
      <th>Last Name</th>
      <th>Native Language</th>
      <th>Learning Language</th>
      <th>Admin?</th>
      <th colspan="3"></th>
     </tr>
   </thead>

   <tbody>
    <% @users.each do |user| %>
     <tr>
      <td><%= user.first_name %></td>
      <td><%= user.last_name %></td>
      <td><%#= user.meeting_time %></td>
      <td><%= user.admin %></td>
      <td><%=  %></td>
      <td><%=  %></td>
      <td><%= link_to 'Edit', edit_user_path(user) %></td>
     <% end %>
    </tr>
   </tbody>
  </table>

edit view

 <h2>Edit <%= resource_name.to_s.humanize %></h2>

  <%= form_for(resource, as: resource_name, url: registration_path(resource_name), html: { method: :put }) do |f| %>
  <%= devise_error_messages! %>

  <div class="field">
    <%= f.label :first_name %>
    <%= f.text_field :first_name, autofocus: true %>
  </div>
  <div class="field">
     <%= f.label :current_password %> <i>(we need your current password to confirm your changes)</i><br />
     <%= f.password_field :current_password, autocomplete: "off" %>
  </div>
  <div class="form-group">
   <%= f.label :admin %>
   <%= f.check_box :admin %>
  </div>
  <div class="actions">
   <%= f.submit "Update" %>
  </div>
<% end %>

Still very new to rails, so please let me know if I need to post anything else. Thanks!

UPDATE

profiler_controller.rb

  def admin_view
    @users = User.all
  end

Answer 1

This is a case for authorization (whether a user has permission).

As you've rightly stated, you can use CanCanCan ( CanCan is no longer maintained) to do this, although there are many similar gems such as Pundit etc.

If using CanCanCan , I would use the following:

---

#config/routes.rb
resources :users do
  post :admin #-> url.com/users/:user_id/admin
end

#app/models/ability.rb
class Ability
  include CanCan::Ability

  def initialize(user)
    user ||= User.new # guest user (not logged in)
    if user.admin?
      can :manage, :user
    end
  end
end

This will allow you to use:

#app/views/admin/users/index.html.erb
<% @users.each do |user| %>
  <tr>
    <td><%= user.first_name %></td>
    <td><%= user.last_name %></td>
    <td><%= user.admin %></td>
    <td><%= link_to "Admin?", user_admin_path(user), method: :post if can? :manage, user %></td>
    <td><%= link_to 'Edit', edit_user_path(user) %></td>
  </tr>
<% end %>

#app/controllers/users_controller.rb
class UsersController < ApplicationController 
  def admin
    @user = User.find params[:user_id]
    @user.toggle :admin if can? :manage, @user
    redirect_to @user 
  end
end

I can provide more if required; this should answer your question though.