Return webfinger for ap_ids.

lib/pleroma/web/web_finger/web_finger.ex

@@ -18,11 +18,15 @@ defmodule Pleroma.Web.WebFinger do
   def webfinger(resource) do
     host = Pleroma.Web.host
     regex = ~r/(acct:)?(?<username>\w+)@#{host}/
-    case Regex.named_captures(regex, resource) do
+    with %{"username" => username} <- Regex.named_captures(regex, resource) do
-      %{"username" => username} ->
       user = User.get_by_nickname(username)
       {:ok, represent_user(user)}
-      _ -> nil
+    else _e ->
+      with user when not is_nil(user) <- User.get_cached_by_ap_id(resource) do
+        {:ok, represent_user(user)}
+      else _e ->
+        {:error, "Couldn't find user"}
+      end
     end
   end
 

test/web/web_finger/web_finger_test.exs

@@ -11,6 +11,22 @@ defmodule Pleroma.Web.WebFingerTest do
     end
   end
 
+  describe "incoming webfinger request" do
+    test "works for fqns" do
+      user = insert(:user)
+
+      {:ok, result} = WebFinger.webfinger("#{user.nickname}@#{Pleroma.Web.host}")
+      assert is_binary(result)
+    end
+
+    test "works for ap_ids" do
+      user = insert(:user)
+
+      {:ok, result} = WebFinger.webfinger(user.ap_id)
+      assert is_binary(result)
+    end
+  end
+
   describe "fingering" do
     test "returns the info for a user" do
       user = "shp@social.heldscal.la"