5. Boundary: GenServer Clock

Mix.install([
  {:kino, "~> 0.6.2"}
])

import IEx.Helpers

Notes

h(GenServer)

h(Kino.start_child() / 1)

Lab: GenServer Clock

defmodule Clock do
  use GenServer

  # Callbacks

  @impl true
  def init({adapter, options}) do
    # periodically send ticks
    {:ok, adapter.new(options)}
  end

  @impl true
  def handle_call(:tick, _from, clock) do
    {:reply, :rendered_clock, :next_clock_state}
  end

  def start_link(options) do
    GenServer.start_link(__MODULE__, options, name: __MODULE__)
  end

  def tick() do
    GenServer.call(__MODULE__, :tick)
  end
end

Lab: Kino Lifecycle Clock

# start your GenServer here