Watch all Phoenix.LiveView and LiveComponent handle_event callbacks

PASTE_ME.exs

(fn gl ->
  :dbg.stop_clear()

  repr = fn
    %Phoenix.LiveView.Socket{} -> "socket"
    v -> inspect(v)
  end

  {:ok, _} =
    :dbg.tracer(
      :process,
      {fn
         {:trace, pid, :call, {module, function, args}}, _ ->
           IO.puts(gl, [
             [inspect(pid), ": ", inspect(module), ".", Atom.to_string(function), "("],
             args |> Enum.map(repr) |> Enum.intersperse(", "),
             ")"
           ])
       end, :state}
    )

  :dbg.p(:all, [:call])

  for {app, _desc, _version} <- :application.loaded_applications(),
      {:ok, modules} = :application.get_key(app, :modules),
      module <- modules,
      Kernel.function_exported?(module, :__live__, 0),
      do: :dbg.tpl(module, :handle_event, [{:_, [], []}])
end).(Process.group_leader())

Paste the above at the iex> prompt to print out the function calls being made to your handle_event callbacks:

MyApp.MyViewLive.handle_event("change", %{"_csrf_token" => "...", "param" => "value"}}, socket)

Works on remote prompts, because Process.group_leader(); see Pretty for more detail on how that works.