Rails Admin Devise - How to edit other users? - ruby-on-rails

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As you've rightly stated, you can use CanCanCan (CanCan is no longer maintained) to do this, although there are many similar gems such as Pundit etc.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