Provide metrics on root URL

test/kafkaex_lag_exporter_web/views/error_view_test.exs

@@ -0,0 +1,17 @@
+defmodule KafkaexLagExporterWeb.ErrorViewTest do
+  use KafkaexLagExporterWeb.ConnCase, async: true
+
+  # Bring render/3 and render_to_string/3 for testing custom views
+  import Phoenix.View
+
+  test "renders 404.json" do
+    assert render(KafkaexLagExporterWeb.ErrorView, "404.json", []) == %{
+             errors: %{detail: "Not Found"}
+           }
+  end
+
+  test "renders 500.json" do
+    assert render(KafkaexLagExporterWeb.ErrorView, "500.json", []) ==
+             %{errors: %{detail: "Internal Server Error"}}
+  end
+end

test/support/channel_case.ex

@@ -0,0 +1,34 @@
+defmodule KafkaexLagExporterWeb.ChannelCase do
+  @moduledoc """
+  This module defines the test case to be used by
+  channel tests.
+
+  Such tests rely on `Phoenix.ChannelTest` and also
+  import other functionality to make it easier
+  to build common data structures and query the data layer.
+
+  Finally, if the test case interacts with the database,
+  we enable the SQL sandbox, so changes done to the database
+  are reverted at the end of every test. If you are using
+  PostgreSQL, you can even run database tests asynchronously
+  by setting `use KafkaexLagExporterWeb.ChannelCase, async: true`, although
+  this option is not recommended for other databases.
+  """
+
+  use ExUnit.CaseTemplate
+
+  using do
+    quote do
+      # Import conveniences for testing with channels
+      import Phoenix.ChannelTest
+      import KafkaexLagExporterWeb.ChannelCase
+
+      # The default endpoint for testing
+      @endpoint KafkaexLagExporterWeb.Endpoint
+    end
+  end
+
+  setup _tags do
+    :ok
+  end
+end

test/support/conn_case.ex

@@ -0,0 +1,37 @@
+defmodule KafkaexLagExporterWeb.ConnCase do
+  @moduledoc """
+  This module defines the test case to be used by
+  tests that require setting up a connection.
+
+  Such tests rely on `Phoenix.ConnTest` and also
+  import other functionality to make it easier
+  to build common data structures and query the data layer.
+
+  Finally, if the test case interacts with the database,
+  we enable the SQL sandbox, so changes done to the database
+  are reverted at the end of every test. If you are using
+  PostgreSQL, you can even run database tests asynchronously
+  by setting `use KafkaexLagExporterWeb.ConnCase, async: true`, although
+  this option is not recommended for other databases.
+  """
+
+  use ExUnit.CaseTemplate
+
+  using do
+    quote do
+      # Import conveniences for testing with connections
+      import Plug.Conn
+      import Phoenix.ConnTest
+      import KafkaexLagExporterWeb.ConnCase
+
+      alias KafkaexLagExporterWeb.Router.Helpers, as: Routes
+
+      # The default endpoint for testing
+      @endpoint KafkaexLagExporterWeb.Endpoint
+    end
+  end
+
+  setup _tags do
+    {:ok, conn: Phoenix.ConnTest.build_conn()}
+  end
+end