[#1427] Extra check that admin OAuth scope is used by admin. Adjusted tests.

lib/pleroma/plugs/user_is_admin_plug.ex

@@ -6,29 +6,37 @@ defmodule Pleroma.Plugs.UserIsAdminPlug do
   import Pleroma.Web.TranslationHelpers
   import Plug.Conn
 
+  alias Pleroma.User
   alias Pleroma.Web.OAuth
 
   def init(options) do
     options
   end
 
-  def call(%Plug.Conn{assigns: assigns} = conn, _) do
+  def call(%{assigns: %{user: %User{is_admin: true}} = assigns} = conn, _) do
     token = assigns[:token]
-    user = assigns[:user]
 
     cond do
+      not Pleroma.Config.enforce_oauth_admin_scope_usage?() ->
+        conn
+
       token && OAuth.Scopes.contains_admin_scopes?(token.scopes) ->
         # Note: checking for _any_ admin scope presence, not necessarily fitting requested action.
         #   Thus, controller must explicitly invoke OAuthScopesPlug to verify scope requirements.
         conn
 
-      user && user.is_admin && !Pleroma.Config.enforce_oauth_admin_scope_usage?() ->
-        conn
-
       true ->
-        conn
-        |> render_error(:forbidden, "User is not an admin or OAuth admin scope is not granted.")
-        |> halt()
+        fail(conn)
     end
   end
+
+  def call(conn, _) do
+    fail(conn)
+  end
+
+  defp fail(conn) do
+    conn
+    |> render_error(:forbidden, "User is not an admin or OAuth admin scope is not granted.")
+    |> halt()
+  end
 end

lib/pleroma/user.ex

@@ -1736,7 +1736,8 @@ defmodule Pleroma.User do
 
     with {:ok, updated_user} <- update_and_set_cache(changeset) do
       if user.is_admin && !updated_user.is_admin do
-        # Tokens & authorizations containing any admin scopes must be revoked (revoking all)
+        # Tokens & authorizations containing any admin scopes must be revoked (revoking all).
+        # This is an extra safety measure (tokens' admin scopes won't be accepted for non-admins).
         global_sign_out(user)
       end