Geometrics and testing View Source

When adding Geometrics to a Phoenix project, a plug and a handler is registered. This handler expects that when LiveView connections are made, a traceContext param is sent.

This can cause warnings in live view tests, if the parameter is not configured. This can be done as follows, where the values of traceId and spanId can be set to anything:

defmodule MyAppWeb.PageLiveTest do
  use MyAppWeb.ConnCase

  import Phoenix.LiveViewTest
  alias Phoenix.LiveViewTest

  test "renders", %{conn: conn} do
    {:ok, home_live, disconnected_html} =
      conn
      |> LiveViewTest.put_connect_params(%{
        "traceContext" => %{"traceId" => "11111", "spanId" => "22222"}
      })
      |> live("/")

    assert disconnected_html =~ "Some text"
    assert render(home_live) =~ "Some text"
  end
end

Alternatively, this warning can be disabled entirely for tests by adding the following to config/test.exs:

config :geometrics, :warn_on_no_trace_context, false