     assert "03bd9e" = System.get_env("APP_REVISION")
   end
 
+  defp default_configuration do
+    %{
+      active: false,
+      debug: false,
+      enable_host_metrics: false,
+      endpoint: "https://push.appsignal.com",
+      env: :dev,
+      filter_parameters: nil,
+      ignore_actions: [],
+      ignore_errors: [],
+      running_in_container: false,
+      send_params: true,
+      skip_session_data: false,
+      valid: false
+    }
+  end
+
+  defp valid_configuration do
+    default_configuration
+    |> Map.put(:active, true)
+    |> Map.put(:push_api_key, "00000000-0000-0000-0000-000000000000")
+    |> Map.put(:valid, true)
+  end
+
   defp init_config do
     Config.initialize()
     Application.get_all_env(:appsignal)[:config]
   end
-
 end

  setup do
    Application.delete_env(:appsignal, :config)

    System.delete_env("APPSIGNAL_ACTIVE")
    System.delete_env("APPSIGNAL_ENVIRONMENT")
    System.delete_env("APPSIGNAL_PUSH_API_KEY")
    System.delete_env("APPSIGNAL_APP_NAME")
    System.delete_env("APPSIGNAL_ENABLE_HOST_METRICS")
    System.delete_env("APP_REVISION")
  end

  test "unconfigured" do

    Application.put_env(:appsignal, :config,
      push_api_key: "-test")
    assert :ok = Config.initialize()
  end

  test "default configuration" do
    assert default_configuration == init_config
  end

  test "valid configuration" do
    Application.put_env(
      :appsignal, :config,
      push_api_key: "00000000-0000-0000-0000-000000000000"
    )
    assert valid_configuration == init_config
  end

  test "app revision" do
