Reusable Phoenix.LiveView

list_view.ex

defmodule ListView do

  @callback query(socket :: Phoenix.LiveView.Socket.t()) :: Ecto.Query.t()

  defmacro __using__(opts \\ []) do
    quote bind_quoted: [opts: opts] do
      opts = Keyword.validate!(opts, [:repo, :schema, :per_page])
      @repo Keyword.fetch!(opts, :repo)
      @schema Keyword.get(opts, :schema)
      @per_page Keyword.get(opts, :per_page, 10)

      @behaviour ListView

      use MyAppWeb, :live_view
      import Ecto.Query

      on_mount __MODULE__

      def on_mount(:default, _params, _session, socket) do
        {:cont, assign(socket, schema_list: schema_list(socket))}
      end

      def query(socket) do
        Ecto.Query.from(@schema)
      end

      def schema_list(socket) do
        socket
        |> query()
        |> Ecto.Query.limit(@per_page)
        |> @repo.all()
      end

      def render(var!(assigns)) do
        ~H"""
        <h1>Default render</h1>
        <ul>
          <%= for schema <- @schema_list do %>
            <li><%= inspect schema %></li>
          <% end %>
        </ul>
        """
      end

      defoverridable ListView
      defoverridable render: 1
    end
  end
end

defmodule MyAppWeb.UserLive.List do
  use ListView, repo: MyApp.Repo, schema: MyApp.Accounts.User, per_page: 2
end

defmodule MyAppWeb.UserLive.List do
  use ListView, repo: MyApp.Repo

  def query(socket) do
    Ecto.Query.from(u in MyApp.Accounts.User, where: u.is_active == true)
  end

  def render(assigns) do
    ~H"""
    <h1>override render <%= inspect @schema_list %></h1>
    """
  end
end