Separate extra automatic verification logic to existing module

lib/philomena/artist_links.ex

@@ -14,30 +14,11 @@ defmodule Philomena.ArtistLinks do
   alias Philomena.Tags.Tag
 
   @doc """
-  Check links pending verification to see if the user placed
-  the appropriate code on the page.
+  Updates all links pending verification to transition to link verified or reset
+  next update time.
   """
   def automatic_verify! do
-    now = DateTime.utc_now() |> DateTime.truncate(:second)
-
-    # Automatically retry in an hour if we don't manage to
-    # successfully verify any given link
-    recheck_time = DateTime.add(now, 3600, :second)
-
-    recheck_query =
-      from ul in ArtistLink,
-        where: ul.aasm_state == "unverified",
-        where: ul.next_check_at < ^now
-
-    recheck_query
-    |> Repo.all()
-    |> Enum.map(fn link ->
-      ArtistLink.automatic_verify_changeset(
-        link,
-        AutomaticVerifier.check_link(link, recheck_time)
-      )
-    end)
-    |> Enum.map(&Repo.update!/1)
+    Enum.each(AutomaticVerifier.generate_updates(), &Repo.update!/1)
   end
 
   @doc """

lib/philomena/artist_links/automatic_verifier.ex

@@ -1,5 +1,47 @@
 defmodule Philomena.ArtistLinks.AutomaticVerifier do
-  def check_link(artist_link, recheck_time) do
+  @moduledoc """
+  Artist link automatic verification.
+
+  Artist links contain a random code which is generated when the link is created. If the user
+  places the code on their linked page and this verifier finds it, this expedites the process
+  of verifying a link for the moderator, as they can simply use the presence of the code in a
+  field controlled by the artist to ascertain the validity of the artist link.
+  """
+
+  alias Philomena.ArtistLinks.ArtistLink
+  alias Philomena.Repo
+  import Ecto.Query
+
+  @doc """
+  Check links pending verification to see if the user placed the appropriate code on the page.
+
+  Polls each artist link in unverified state and generates a changeset to either set it to
+  link verified, if the code was found on the page, or reset the next check time, if the code
+  was not found.
+
+  Returns a list of changesets with updated links.
+  """
+  def generate_updates do
+    # Automatically retry in an hour if we don't manage to
+    # successfully verify any given link
+    now = DateTime.utc_now(:second)
+    recheck_time = DateTime.add(now, 3600, :second)
+
+    Enum.map(links_to_check(now), fn link ->
+      ArtistLink.automatic_verify_changeset(link, check_link(link, recheck_time))
+    end)
+  end
+
+  defp links_to_check(now) do
+    recheck_query =
+      from ul in ArtistLink,
+        where: ul.aasm_state == "unverified",
+        where: ul.next_check_at < ^now
+
+    Repo.all(recheck_query)
+  end
+
+  defp check_link(artist_link, recheck_time) do
     artist_link.uri
     |> PhilomenaProxy.Http.get()
     |> contains_verification_code?(artist_link.verification_code)