Add extractor for finertech.com

lib/frenzy/pipeline/extractor/finertech.ex

@@ -0,0 +1,39 @@
+defmodule Frenzy.Pipeline.Extractor.FinerTech do
+  @moduledoc """
+  Extractor for https://finertech.com
+  """
+
+  alias Frenzy.Pipeline.Extractor
+  @behaviour Extractor
+
+  @impl Extractor
+  def extract(html_tree) do
+    case Floki.find(html_tree, ".entry-content") do
+      [content_elem | _] ->
+        # remove patreon button
+        content_elem = Floki.traverse_and_update(content_elem, &remove_patreon_banner/1)
+        {:ok, content_elem}
+
+      _ ->
+        {:error, "no matching element"}
+    end
+  end
+
+  @patreon_class_regex ~r/[a-z0-9_]patreon_button/i
+
+  defp remove_patreon_banner({"div", attrs, _children} = elem) do
+    case Enum.find(attrs, fn {attr, _val} -> attr == "class" end) do
+      nil ->
+        elem
+
+      {"class", class} ->
+        if Regex.match?(@patreon_class_regex, class) do
+          nil
+        else
+          elem
+        end
+    end
+  end
+
+  defp remove_patreon_banner(elem), do: elem
+end