Added ability to change user roles in admin/users index

app/controllers/admin/users_controller.rb

@@ -1,6 +1,6 @@
 class Admin::UsersController < ApplicationController
+  before_action :set_user, only: [ :show, :update ]
   before_action :authorize!
-  before_action :set_user, only: [ :show, :edit ]
 
   def index
     @users = User.all.order(:lastname, :firstname)
@@ -20,6 +20,14 @@ class Admin::UsersController < ApplicationController
   end
 
   def update
+    authorize! @user
+    if @user.update(user_params)
+      respond_to do |format|
+        format.html { redirect_to admin_users_path }
+      end
+    else
+        render :index, status: :unprocessable_entity
+    end
   end
 
   private
@@ -27,4 +35,8 @@ class Admin::UsersController < ApplicationController
   def set_user
     @user = User.find(params[:id])
   end
+
+  def user_params
+    params.require(:user).permit(:role)
+  end
 end