I have a live_view that uses live_components to swap out the content of the page’s main content area depending on the selected item in the parent. I am having an issue where the live_component’s update/2 function’s params argument always contains ALL parameters including (what is in my world) non-new. I would expect mount/1 to be called once, and it is and update/2 to be called each time an parameter changes and only include the parameters that have changed since the last call to update.

But I see update being passed all the params every time. Am i missing something, or dont i understand what constitudes “new”?

The render in the parent looks something like this:

  @impl true
  def render(assigns) do
    selected_resource = assigns.selected_resource
    page = selected_resource && page_module(selected_resource.type, selected_resource.page)
    assigns = assign(assigns, :page, page)

    ~H"""
    <div class="flex h-screen w-screen bg-green">
      <.side_menu
        project={@project}
        selected_tab={@selected_tab}
        search_active={@search_active}
        selected_resource={@selected_resource}
      />
      <div class="flex-1">
        <.async_result :let={resource} assign={@resource}>
          <:loading>
            Loading...
          </:loading>
          <:failed>
            Failed to fetch resource
          </:failed>

          <.live_component
            :if={@page}
            id="page"
            module={@page}
            resource={resource}
            resource_id={@selected_resource}
            project_id={@project_id}
            current_user={@current_user}
            timezone={@timezone}
          />
        </.async_result>
      </div>
    </div>
    """
  end

My live_component update function does:

Map.keys(params) #=> [:id, :resource, :current_user, :resource_id, :timezone, :project_id]

And outputs the same keys every time update is called.