refactor(anti-spam): make anti-spam agnostic from Akismet

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/anti_spam/provider.ex

@@ -0,0 +1,58 @@
+defmodule Mobilizon.Service.AntiSpam.Provider do
+  @moduledoc """
+  Provider Behaviour for anti-spam detection.
+
+  ## Supported backends
+
+    * `Mobilizon.Service.AntiSpam.Akismet` [🔗](https://akismet.com/)
+
+  """
+
+  @type spam_result :: :ham | :spam | :discard
+  @type result :: spam_result() | {:error, any()}
+
+  @doc """
+  Make sure the provider is ready
+  """
+  @callback ready?() :: boolean()
+
+  @doc """
+  Check an user details
+  """
+  @callback check_user(email :: String.t(), ip :: String.t(), user_agent :: String.t()) ::
+              result()
+
+  @doc """
+  Check a profile details
+  """
+  @callback check_profile(
+              username :: String.t(),
+              summary :: String.t(),
+              email :: String.t() | nil,
+              ip :: String.t(),
+              user_agent :: String.t() | nil
+            ) :: result()
+
+  @doc """
+  Check an event details
+  """
+  @callback check_event(
+              event_body :: String.t(),
+              username :: String.t(),
+              email :: String.t() | nil,
+              ip :: String.t(),
+              user_agent :: String.t() | nil
+            ) :: result()
+
+  @doc """
+  Check a comment details
+  """
+  @callback check_comment(
+              comment_body :: String.t(),
+              username :: String.t(),
+              is_reply? :: boolean(),
+              email :: String.t() | nil,
+              ip :: String.t(),
+              user_agent :: String.t() | nil
+            ) :: result()
+end