Hello and thanks, your answer is really helpfull!
I will try the :sys.trace/2 thing first thing tomorrow morning. As of my setup and code :
Here is my genserver’s code (code insights welcome as well, still not really comfortable with it) :
defmodule MyApp.MyExternalAppModule do
use GenServer
@external_app_node Application.get_env(:my_app, :external_app_node)
@mailer Application.get_env(:my_app, :mailer)
def start_link(_args) do
GenServer.start_link(__MODULE__, %{}, name: __MODULE__)
end
def insert(field1, field2, field3) do
GenServer.call(__MODULE__, {:insert, field1, field2, field3})
end
def init(%{}) do
{:ok, %{ref: nil}}
end
def handle_call(
{:insert, _field1, _field2, _field3},
_from,
%{ref: ref} = state
)
when is_reference(ref) do
{:reply, :ok, state}
end
def handle_call({:insert, field1, field2, field3}, _from, %{ref: nil}) do
task =
Task.Supervisor.async_nolink(
{MyExternalApp.TaskSupervisor, @external_app_node},
MyExternalApp.MyExternalAppModule,
:my_function,
[field1, field2, field3]
)
{:reply, :ok, %{field1: field1, field2: field2, field3: field3, ref: task.ref}}
end
def handle_info(
{ref, {:ok, _external_element}},
%{ref: ref, field1: field1, field2: field2, field3: field3} = state
) do
Process.demonitor(ref, [:flush])
@mailer.send_mail("(...)success")
{:noreply, %{state | ref: nil}}
end
def handle_info(
{ref, {:error, reason}},
%{ref: ref, field1: field1, field2: field2, field3: field3} = state
)
when is_atom(reason) do
Process.demonitor(ref, [:flush])
@mailer.send_mail("(...)failure")
{:noreply, %{state | ref: nil}}
end
def handle_info(
{ref, {:error, _changeset}},
%{ref: ref, field1: field1, field2: field2, field3: field3} = state
) do
Process.demonitor(ref, [:flush])
@mailer.send_mail("(...)failure")
{:noreply, %{state | ref: nil}}
end
end
Tests :
defmodule MyApp.MyExternalAppModuleTest do
use ExUnit.Case, async: true
@my_external_app_module Application.get_env(:my_app, :my_external_app_module)
describe "insert/3" do
test "when my_external_app node is up and the data exists returns (TODO)" do
assert :ok == @my_external_app_module.insert("field1", "field2", "field3")
assert_receive {_, {:ok, _}}, 3000
end
end
end
And you’re right, my GenServer is started by the Supervisor! Didn’t get that would be a problem…
