Update the navbar and routes to check the User's role.

lib/decentralised_book_index_web/components/my_partials/navbar.ex

@@ -4,6 +4,7 @@ defmodule DecentralisedBookIndexWeb.Components.MyPartials.Navbar do
 
   import DecentralisedBookIndexWeb.Components.MyComponents.Buttons
   alias Phoenix.LiveView.JS
+  alias DecentralisedBookIndex.Accounts.Role
 
   attr :page_title, :string, required: true
   attr :current_user, :map, default: nil
@@ -28,10 +29,12 @@ defmodule DecentralisedBookIndexWeb.Components.MyPartials.Navbar do
                     <li>
                         <a href={~p"/authors/"} class={selected_navbar_link_css(@page_title, "Listing Authors")} aria-current="page">Authors</a>
                     </li>
-                    <%= if @current_user != nil do %>
+                    <%= if @current_user != nil and Role.can_moderate?(@current_user.role) do %>
                         <li>
                             <a href={~p"/publishers/"} class={selected_navbar_link_css(@page_title, "Listing Publishers")} aria-current="page">Publishers</a>
                         </li>
+                    <% end %>
+                    <%= if @current_user != nil and Role.can_administrate?(@current_user.role) do %>
                         <li>
                             <a href={~p"/servers/"} class={selected_navbar_link_css(@page_title, "Listing Server")} aria-current="page">Servers</a>
                         </li>