Pass around settings as module instead of Map

lib/boom_notifier.ex

@@ -8,8 +8,20 @@ defmodule BoomNotifier do
   alias BoomNotifier.ErrorInfo
   alias BoomNotifier.NotificationSender
 
+  @spec to_config(Keyword.t() | Atom) :: Keyword.t()
+  def to_config(config) when is_atom(config),
+    do: config.boom_config()
+
+  def to_config(settings),
+    do: settings
+
+  @doc """
+  Runs BoomNotifier triggering logic according to the provided configuration which
+  can be specified either as a keyword list or as a module atom which uses BoomNotifier.
+  """
+  @spec notify_error(Keyword.t(), Plug.Conn.t(), error :: any()) :: nil
   def notify_error(settings, conn, %{kind: :error, reason: %mod{}} = error) do
-    ignored_exceptions = Keyword.get(settings, :ignore_exceptions, [])
+    ignored_exceptions = Keyword.get(to_config(settings), :ignore_exceptions, [])
 
     unless Enum.member?(ignored_exceptions, mod) do
       trigger_notify_error(settings, conn, error)
@@ -44,24 +56,15 @@ defmodule BoomNotifier do
   end
 
   defp run_callback(settings, callback) do
-    missing_keys = Enum.reject([:notifier, :options], &Keyword.has_key?(settings, &1))
-
-    case missing_keys do
-      [] ->
-        callback.(settings[:notifier], settings[:options])
-
-      [missing_key] ->
-        Logger.error("(BoomNotifier) #{inspect(missing_key)} parameter is missing")
-
-      _ ->
-        Logger.error(
-          "(BoomNotifier) The following parameters are missing: #{inspect(missing_keys)}"
-        )
+    if Keyword.has_key?(settings, :notifier) do
+      callback.(settings[:notifier], settings[:options])
+    else
+      Logger.error("Parameter :notifier is missing in #{inspect(settings)}")
     end
   end
 
   defp trigger_notify_error(settings, conn, error) do
-    custom_data = Keyword.get(settings, :custom_data, :nothing)
+    custom_data = Keyword.get(to_config(settings), :custom_data, :nothing)
     error_info = ErrorInfo.build(error, conn, custom_data)
 
     NotificationSender.async_trigger_notify(settings, error_info)
@@ -91,7 +94,11 @@ defmodule BoomNotifier do
       )
 
       def notify_error(conn, error) do
-        BoomNotifier.notify_error(unquote(config), conn, error)
+        BoomNotifier.notify_error(__MODULE__, conn, error)
+      end
+
+      def boom_config do
+        unquote(config)
       end
     end
   end

lib/boom_notifier/notification_sender.ex

@@ -39,7 +39,15 @@ defmodule BoomNotifier.NotificationSender do
     )
   end
 
+  @doc """
+  Call notifiers if error_info should trigger a notification
+  according to settings and the acumulated errors.
+
+  It returns :ok if notification were triggered or {:schedule, time}
+  if it should be delayed and by how much.
+  """
   def trigger_notify(settings, error_info) do
+    settings = BoomNotifier.to_config(settings)
     timeout = Keyword.get(settings, :time_limit)
 
     ErrorStorage.store_error(error_info)

test/unit/boom_notifier_test.exs

@@ -0,0 +1,30 @@
+defmodule BoomNotifier.BoomNotifierTest do
+  use BoomNotifier.Case
+
+  defmodule FakeNotifier do
+    def notify(_, _), do: nil
+  end
+
+  describe "to_config/1" do
+    defmodule ToConfigEndpoint do
+      def call(conn, _opts), do: conn
+
+      use BoomNotifier,
+        notifier: FakeNotifier
+    end
+
+    test "accepts a module name" do
+      assert BoomNotifier.to_config(ToConfigEndpoint) == ToConfigEndpoint.boom_config()
+    end
+
+    test "it calls boom_notifier when a module is specified" do
+      assert_raise(UndefinedFunctionError, fn ->
+        BoomNotifier.to_config(Kernel)
+      end)
+    end
+
+    test "accepts a keyword list" do
+      assert BoomNotifier.to_config(notifier: FakeNotifier) == ToConfigEndpoint.boom_config()
+    end
+  end
+end

test/unit/notifier_test.exs

@@ -319,24 +319,6 @@ defmodule NotifierTest do
     :elixir_config.put(:ignore_module_conflict, false)
   end
 
-  test "logs when parameters in config are missing" do
-    :elixir_config.put(:ignore_module_conflict, true)
-
-    conn = conn(:get, "/")
-
-    assert capture_log(fn ->
-             defmodule PlugLogWithMissingParameterNotifier do
-               use BoomNotifier, other: nil
-
-               def call(_conn, _opts) do
-                 raise TestException.exception([])
-               end
-             end
-           end) =~ "(BoomNotifier) The following parameters are missing: [:notifier, :options]"
-
-    :elixir_config.put(:ignore_module_conflict, false)
-  end
-
   test "logs when one parameter in config is missing" do
     conn = conn(:get, "/")
 
@@ -351,7 +333,7 @@ defmodule NotifierTest do
                  raise TestException.exception([])
                end
              end
-           end) =~ "(BoomNotifier) :notifier parameter is missing"
+           end) =~ "Parameter :notifier is missing"
   end
 
   describe "ignored exceptions" do