Merge pull request 'Fix System missing system actor in prod and prevent deletion' (#379) from fix/system_actor into main

Reviewed-on: #379

lib/accounts/user.ex

@@ -86,7 +86,13 @@ defmodule Mv.Accounts.User do
     #       - :create_user (for manual user creation with optional member link)
     #       - :register_with_password (for password-based registration)
     #       - :register_with_rauthy (for OIDC-based registration)
-    defaults [:read, :destroy]
+    defaults [:read]
+
+    destroy :destroy do
+      primary? true
+      # Required because custom validation (system actor protection) cannot run atomically
+      require_atomic? false
+    end
 
     # Primary generic update action:
     # - Selected by AshAdmin's generated "Edit" UI and generic AshPhoenix
@@ -169,6 +175,13 @@ defmodule Mv.Accounts.User do
       end
     end
 
+    # Internal update used only by SystemActor/bootstrap and tests to assign role to system user.
+    # Not protected by system-user validation so bootstrap can run.
+    update :update_internal do
+      accept []
+      require_atomic? false
+    end
+
     # Admin action for direct password changes in admin panel
     # Uses the official Ash Authentication HashPasswordChange with correct context
     update :admin_set_password do
@@ -359,6 +372,21 @@ defmodule Mv.Accounts.User do
         :ok
       end
     end
+
+    # Prevent modification of the system actor user (required for internal operations).
+    # Block update/destroy on UI-exposed actions only; :update_internal is used by bootstrap/tests.
+    validate fn changeset, _context ->
+               if Mv.Helpers.SystemActor.system_user?(changeset.data) do
+                 {:error,
+                  field: :email,
+                  message:
+                    "Cannot modify system actor user. This user is required for internal operations."}
+               else
+                 :ok
+               end
+             end,
+             on: [:update, :destroy],
+             where: [action_is([:update, :update_user, :admin_set_password, :destroy])]
   end
 
   def validate_oidc_id_present(changeset, _context) do

lib/mv/helpers/system_actor.ex

@@ -172,6 +172,31 @@ defmodule Mv.Helpers.SystemActor do
     end
   end
 
+  @doc """
+  Returns whether the given user is the system actor user (case-insensitive email match).
+
+  Use this instead of ad-hoc `to_string(user.email) == system_user_email()` so
+  comparisons are consistent and case-insensitive everywhere.
+
+  ## Returns
+
+  - `boolean()` - true if user's email matches system user email (case-insensitive)
+
+  ## Examples
+
+      iex> Mv.Helpers.SystemActor.system_user?(user_with_system_email)
+      true
+      iex> Mv.Helpers.SystemActor.system_user?(other_user)
+      false
+
+  """
+  @spec system_user?(Mv.Accounts.User.t() | map() | nil) :: boolean()
+  def system_user?(%{email: email}) when not is_nil(email) do
+    normalized_email(to_string(email)) == normalized_system_user_email()
+  end
+
+  def system_user?(_), do: false
+
   @doc """
   Returns the email address of the system user.
 
@@ -191,6 +216,11 @@ defmodule Mv.Helpers.SystemActor do
   @spec system_user_email() :: String.t()
   def system_user_email, do: system_user_email_config()
 
+  # Case-insensitive normalized form for comparisons
+  defp normalized_system_user_email, do: normalized_email(system_user_email_config())
+
+  defp normalized_email(email) when is_binary(email), do: String.downcase(email)
+
   # Returns the system user email from environment variable or default
   # This allows configuration via SYSTEM_ACTOR_EMAIL env var
   @spec system_user_email_config() :: String.t()
@@ -368,7 +398,7 @@ defmodule Mv.Helpers.SystemActor do
       upsert_identity: :unique_email,
       authorize?: false
     )
-    |> Ash.Changeset.for_update(:update, %{})
+    |> Ash.Changeset.for_update(:update_internal, %{})
     |> Ash.Changeset.manage_relationship(:role, admin_role, type: :append_and_remove)
     |> Ash.update!(authorize?: false)
     |> Ash.load!(:role, domain: Mv.Accounts, authorize?: false)

lib/mv_web/error_helpers.ex

@@ -0,0 +1,25 @@
+defmodule MvWeb.ErrorHelpers do
+  @moduledoc """
+  Shared helpers for formatting errors in the web layer.
+
+  Use `format_ash_error/1` for Ash errors so behaviour stays consistent
+  (e.g. handling Invalid errors whose entries may lack a `:message` field).
+  """
+
+  @doc """
+  Formats an Ash error for display to the user.
+
+  Handles `Ash.Error.Invalid` by joining error messages; entries without
+  a `:message` field are inspected to avoid FunctionClauseError.
+  Other errors are inspected.
+  """
+  @spec format_ash_error(Ash.Error.t() | term()) :: String.t()
+  def format_ash_error(%Ash.Error.Invalid{errors: errors}) when is_list(errors) do
+    Enum.map_join(errors, ", ", fn
+      %{message: message} when is_binary(message) -> message
+      other -> inspect(other)
+    end)
+  end
+
+  def format_ash_error(error), do: inspect(error)
+end

lib/mv_web/live/user_live/form.ex

@@ -264,12 +264,31 @@ defmodule MvWeb.UserLive.Form do
   def mount(params, _session, socket) do
     actor = current_actor(socket)
 
-    user =
-      case params["id"] do
-        nil -> nil
-        id -> Ash.get!(Mv.Accounts.User, id, domain: Mv.Accounts, load: [:member], actor: actor)
+    case load_user_or_redirect(params["id"], actor, socket) do
+      {:redirect, socket} ->
+        {:ok, socket}
+
+      {:ok, user} ->
+        mount_continue(user, params, socket)
+    end
   end
 
+  defp load_user_or_redirect(nil, _actor, _socket), do: {:ok, nil}
+
+  defp load_user_or_redirect(id, actor, socket) do
+    user = Ash.get!(Mv.Accounts.User, id, domain: Mv.Accounts, load: [:member], actor: actor)
+
+    if Mv.Helpers.SystemActor.system_user?(user) do
+      {:redirect,
+       socket
+       |> put_flash(:error, gettext("This user cannot be edited."))
+       |> push_navigate(to: ~p"/users")}
+    else
+      {:ok, user}
+    end
+  end
+
+  defp mount_continue(user, params, socket) do
     action = if is_nil(user), do: gettext("New"), else: gettext("Edit")
     page_title = action <> " " <> gettext("User")
 

lib/mv_web/live/user_live/index.ex

@@ -25,10 +25,18 @@ defmodule MvWeb.UserLive.Index do
 
   import MvWeb.LiveHelpers, only: [current_actor: 1]
 
+  require Ash.Query
+  import MvWeb.ErrorHelpers, only: [format_ash_error: 1]
+
   @impl true
   def mount(_params, _session, socket) do
     actor = current_actor(socket)
-    users = Ash.read!(Mv.Accounts.User, domain: Mv.Accounts, load: [:member], actor: actor)
+
+    users =
+      Mv.Accounts.User
+      |> Ash.Query.filter(email != ^Mv.Helpers.SystemActor.system_user_email())
+      |> Ash.read!(domain: Mv.Accounts, load: [:member], actor: actor)
+
     sorted = Enum.sort_by(users, & &1.email)
 
     {:ok,
@@ -64,7 +72,7 @@ defmodule MvWeb.UserLive.Index do
              )}
 
           {:error, error} ->
-            {:noreply, put_flash(socket, :error, format_error(error))}
+            {:noreply, put_flash(socket, :error, format_ash_error(error))}
         end
 
       {:error, %Ash.Error.Query.NotFound{}} ->
@@ -75,7 +83,7 @@ defmodule MvWeb.UserLive.Index do
          put_flash(socket, :error, gettext("You do not have permission to access this user"))}
 
       {:error, error} ->
-        {:noreply, put_flash(socket, :error, format_error(error))}
+        {:noreply, put_flash(socket, :error, format_ash_error(error))}
     end
   end
 
@@ -137,12 +145,4 @@ defmodule MvWeb.UserLive.Index do
   defp toggle_order(:desc), do: :asc
   defp sort_fun(:asc), do: &<=/2
   defp sort_fun(:desc), do: &>=/2
-
-  defp format_error(%Ash.Error.Invalid{errors: errors}) do
-    Enum.map_join(errors, ", ", fn %{message: message} -> message end)
-  end
-
-  defp format_error(error) do
-    inspect(error)
-  end
 end

lib/mv_web/live/user_live/show.ex

@@ -75,9 +75,16 @@ defmodule MvWeb.UserLive.Show do
     actor = current_actor(socket)
     user = Ash.get!(Mv.Accounts.User, id, domain: Mv.Accounts, load: [:member], actor: actor)
 
+    if Mv.Helpers.SystemActor.system_user?(user) do
+      {:ok,
+       socket
+       |> put_flash(:error, gettext("This user cannot be viewed."))
+       |> push_navigate(to: ~p"/users")}
+    else
       {:ok,
        socket
        |> assign(:page_title, gettext("Show User"))
        |> assign(:user, user)}
     end
+  end
 end

priv/gettext/de/LC_MESSAGES/default.po

@@ -2125,3 +2125,13 @@ msgstr "E-Mail"
 #, elixir-autogen, elixir-format
 msgid "email %{email} has already been taken"
 msgstr "E-Mail %{email} wurde bereits verwendet"
+
+#: lib/mv_web/live/user_live/form.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be edited."
+msgstr "Dieser Benutzer kann nicht bearbeitet werden."
+
+#: lib/mv_web/live/user_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be viewed."
+msgstr "Dieser Benutzer kann nicht angezeigt werden."

priv/gettext/default.pot

@@ -2126,3 +2126,13 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "email %{email} has already been taken"
 msgstr ""
+
+#: lib/mv_web/live/user_live/form.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be edited."
+msgstr ""
+
+#: lib/mv_web/live/user_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be viewed."
+msgstr ""

priv/gettext/en/LC_MESSAGES/default.po

@@ -2126,3 +2126,13 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "email %{email} has already been taken"
 msgstr ""
+
+#: lib/mv_web/live/user_live/form.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be edited."
+msgstr ""
+
+#: lib/mv_web/live/user_live/show.ex
+#, elixir-autogen, elixir-format
+msgid "This user cannot be viewed."
+msgstr ""

priv/repo/migrations/20260127124937_ensure_system_actor_user_exists.exs

@@ -0,0 +1,62 @@
+defmodule Mv.Repo.Migrations.EnsureSystemActorUserExists do
+  @moduledoc """
+  Ensures the system actor user always exists.
+
+  The system actor is used for systemic operations (email sync, cycle generation,
+  background jobs). It is created by seeds in development; in production seeds
+  may not run, so this migration guarantees the user exists.
+
+  Creates a user with email "system@mila.local" (default from Mv.Helpers.SystemActor)
+  and the Admin role. The user has no password and no OIDC ID, so it cannot log in.
+  """
+  use Ecto.Migration
+  import Ecto.Query
+
+  @system_user_email "system@mila.local"
+
+  def up do
+    admin_role_id = ensure_admin_role_exists()
+    ensure_system_actor_user_exists(admin_role_id)
+  end
+
+  def down do
+    # Not reversible - do not delete system user on rollback
+    :ok
+  end
+
+  defp ensure_admin_role_exists do
+    case repo().one(from(r in "roles", where: r.name == "Admin", select: r.id)) do
+      nil ->
+        execute("""
+        INSERT INTO roles (id, name, description, permission_set_name, is_system_role, inserted_at, updated_at)
+        VALUES (uuid_generate_v7(), 'Admin', 'Administrator with full access', 'admin', false, (now() AT TIME ZONE 'utc'), (now() AT TIME ZONE 'utc'))
+        """)
+
+        role_id = repo().one(from(r in "roles", where: r.name == "Admin", select: r.id))
+        IO.puts("✅ Created 'Admin' role (was missing)")
+        role_id
+
+      role_id ->
+        role_id
+    end
+  end
+
+  defp ensure_system_actor_user_exists(_admin_role_id) do
+    case repo().one(from(u in "users", where: u.email == ^@system_user_email, select: u.id)) do
+      nil ->
+        # Use subquery for role_id to avoid nil/empty-string UUID (CI can lag after role insert)
+        execute("""
+        INSERT INTO users (id, email, hashed_password, oidc_id, member_id, role_id)
+        SELECT uuid_generate_v7(), '#{@system_user_email}', NULL, NULL, NULL, r.id
+        FROM roles r
+        WHERE r.name = 'Admin'
+        LIMIT 1
+        """)
+
+        IO.puts("✅ Created system actor user (#{@system_user_email})")
+
+      _ ->
+        :ok
+    end
+  end
+end

priv/repo/seeds.exs

@@ -268,9 +268,9 @@ case Accounts.User
      |> Ash.read_one(domain: Mv.Accounts, authorize?: false) do
   {:ok, existing_system_user} when not is_nil(existing_system_user) ->
     # System user already exists - ensure it has admin role
-    # Use authorize?: false for bootstrap
+    # Use authorize?: false for bootstrap; :update_internal bypasses system-user modification block
     existing_system_user
-    |> Ash.Changeset.for_update(:update, %{})
+    |> Ash.Changeset.for_update(:update_internal, %{})
     |> Ash.Changeset.manage_relationship(:role, admin_role, type: :append_and_remove)
     |> Ash.update!(authorize?: false)
 
@@ -287,7 +287,7 @@ case Accounts.User
       upsert_identity: :unique_email,
       authorize?: false
     )
-    |> Ash.Changeset.for_update(:update, %{})
+    |> Ash.Changeset.for_update(:update_internal, %{})
     |> Ash.Changeset.manage_relationship(:role, admin_role, type: :append_and_remove)
     |> Ash.update!(authorize?: false)
 

test/mv/helpers/system_actor_test.exs

@@ -10,6 +10,14 @@ defmodule Mv.Helpers.SystemActorTest do
 
   require Ash.Query
 
+  # Deletes a user row directly via SQL, bypassing Ash validations.
+  # Use only in tests when setting up "no system user" / "no users" scenarios;
+  # Ash.destroy! forbids deleting the system actor user.
+  defp delete_user_bypass_ash(user) do
+    id = Ecto.UUID.dump!(user.id)
+    Ecto.Adapters.SQL.query!(Mv.Repo, "DELETE FROM users WHERE id = $1", [id])
+  end
+
   # Helper function to ensure admin role exists
   defp ensure_admin_role do
     case Authorization.list_roles() do
@@ -49,7 +57,7 @@ defmodule Mv.Helpers.SystemActorTest do
          |> Ash.read_one(domain: Mv.Accounts, authorize?: false) do
       {:ok, user} when not is_nil(user) ->
         user
-        |> Ash.Changeset.for_update(:update, %{})
+        |> Ash.Changeset.for_update(:update_internal, %{})
         |> Ash.Changeset.manage_relationship(:role, admin_role, type: :append_and_remove)
         |> Ash.update!(authorize?: false)
         |> Ash.load!(:role, domain: Mv.Accounts, authorize?: false)
@@ -60,7 +68,7 @@ defmodule Mv.Helpers.SystemActorTest do
           upsert_identity: :unique_email,
           authorize?: false
         )
-        |> Ash.Changeset.for_update(:update, %{})
+        |> Ash.Changeset.for_update(:update_internal, %{})
         |> Ash.Changeset.manage_relationship(:role, admin_role, type: :append_and_remove)
         |> Ash.update!(authorize?: false)
         |> Ash.load!(:role, domain: Mv.Accounts, authorize?: false)
@@ -124,7 +132,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^"system@mila.local")
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -163,7 +171,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^"system@mila.local")
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -177,7 +185,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^admin_email)
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -227,7 +235,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^"system@mila.local")
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -241,7 +249,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^admin_email)
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -275,7 +283,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^"system@mila.local")
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -314,7 +322,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^"system@mila.local")
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -328,7 +336,7 @@ defmodule Mv.Helpers.SystemActorTest do
            |> Ash.Query.filter(email == ^admin_email)
            |> Ash.read_one(domain: Mv.Accounts, actor: system_actor) do
         {:ok, user} when not is_nil(user) ->
-          Ash.destroy!(user, domain: Mv.Accounts, actor: system_actor)
+          delete_user_bypass_ash(user)
 
         _ ->
           :ok
@@ -365,9 +373,9 @@ defmodule Mv.Helpers.SystemActorTest do
 
       system_actor = SystemActor.get_system_actor()
 
-      # Assign wrong role to system user
+      # Assign wrong role to system user (use :update_internal so bootstrap-style update is allowed)
       system_user
-      |> Ash.Changeset.for_update(:update, %{})
+      |> Ash.Changeset.for_update(:update_internal, %{})
       |> Ash.Changeset.manage_relationship(:role, read_only_role, type: :append_and_remove)
       |> Ash.update!(actor: system_actor)
 

test/mv_web/live/user_live/show_test.exs

@@ -154,4 +154,14 @@ defmodule MvWeb.UserLive.ShowTest do
       assert html =~ gettext("Show User") || html =~ to_string(user.email)
     end
   end
+
+  describe "system actor user" do
+    test "redirects to user list when viewing system actor user", %{conn: conn} do
+      system_actor = Mv.Helpers.SystemActor.get_system_actor()
+      conn = conn_with_oidc_user(conn)
+
+      assert {:error, {:live_redirect, %{to: "/users"}}} =
+               live(conn, ~p"/users/#{system_actor.id}")
+    end
+  end
 end

test/mv_web/user_live/form_test.exs

@@ -420,4 +420,14 @@ defmodule MvWeb.UserLive.FormTest do
       assert is_nil(updated_user.member)
     end
   end
+
+  describe "system actor user" do
+    test "redirects to user list when editing system actor user", %{conn: conn} do
+      system_actor = Mv.Helpers.SystemActor.get_system_actor()
+      conn = conn_with_oidc_user(conn, %{email: "admin@example.com"})
+
+      assert {:error, {:live_redirect, %{to: "/users"}}} =
+               live(conn, "/users/#{system_actor.id}/edit")
+    end
+  end
 end

test/mv_web/user_live/index_test.exs

@@ -405,6 +405,27 @@ defmodule MvWeb.UserLive.IndexTest do
     end
   end
 
+  describe "system actor user" do
+    test "does not show system actor user in list", %{conn: conn} do
+      # Ensure system actor exists (e.g. via get_system_actor in conn_with_oidc_user)
+      _system_actor = Mv.Helpers.SystemActor.get_system_actor()
+      system_email = Mv.Helpers.SystemActor.system_user_email()
+
+      conn = conn_with_oidc_user(conn)
+      {:ok, _view, html} = live(conn, "/users")
+
+      refute html =~ system_email,
+             "System actor user (#{system_email}) must not appear in the user list"
+    end
+
+    test "destroying system actor user returns error", %{current_user: current_user} do
+      system_actor = Mv.Helpers.SystemActor.get_system_actor()
+
+      assert {:error, %Ash.Error.Invalid{}} =
+               Ash.destroy(system_actor, domain: Mv.Accounts, actor: current_user)
+    end
+  end
+
   describe "member linking display" do
     test "displays linked member name in user list", %{conn: conn} do
       system_actor = Mv.Helpers.SystemActor.get_system_actor()