Hi, I created a basic LiveView example to test the “broadcast_from” messaging, and it works great. This is my controller:
defmodule HelloWeb.ThermostatLive do
use Phoenix.LiveView
@topic "deployments"
def render(assigns) do
~L"""
<h1>The light is <%= @light_bulb_status %>.</h1>
<button phx-click="on">On</button>
<button phx-click="off">Off</button>
"""
end
def mount(_params, _session, socket) do
HelloWeb.Endpoint.subscribe(@topic)
socket = assign(socket, :light_bulb_status, "off")
{:ok, socket}
end
def handle_event(light_bulb_status, _value, socket) do
HelloWeb.Endpoint.broadcast_from(self(), @topic, "status_change", light_bulb_status)
{:noreply, assign(socket, :light_bulb_status, light_bulb_status)}
end
def handle_info(%{topic: @topic, payload: light_bulb_status}, socket) do
IO.puts "HANDLE BROADCAST FOR"
IO.puts light_bulb_status
{:noreply, assign(socket, :light_bulb_status, light_bulb_status)}
end
end
Now, I would like to change the values of light_bulb_status from an external app. To do that I created an /api endpoint named /api/notify and would like it to send messages to the ThermostatLive controller.
This is my NotifyController:
defmodule HelloWeb.NotifyController do
use HelloWeb, :controller
use Phoenix.LiveView
@topic "deployments"
def get(conn, _params) do
HelloWeb.Endpoint.broadcast_from(self(), @topic, "status_change", "on")
{:noreply, Phoenix.LiveView.assign(socket, :light_bulb_status, "on")}
json(conn, %{result: "get"})
end
end
When I call it from cURL with:
curl -H "Content-Type: application/json" "http://127.0.0.1:4000/api/notify"
I get this:
= Compilation error in file lib/hello_web/controllers/notify_controller.ex ==
** (CompileError) lib/hello_web/controllers/notify_controller.ex:8: undefined function socket/0
(elixir 1.12.3) src/elixir_locals.erl:114: anonymous fn/3 in :elixir_locals.ensure_no_undefined_local/3
(stdlib 3.16.1) erl_eval.erl:685: :erl_eval.do_apply/6
(elixir 1.12.3) lib/kernel/parallel_compiler.ex:319: anonymous fn/4 in Kernel.ParallelCompiler.spawn_workers/7
How can I broadcast messages from my api to the other controller?
