transmogrifier: significantly rework handling of peertube videos, add test

lib/pleroma/web/activity_pub/transmogrifier.ex

@@ -170,8 +170,14 @@ def fix_attachments(%{"attachment" => attachment} = object) when is_list(attachm
     attachments =
       attachment
       |> Enum.map(fn data ->
-        url = [%{"type" => "Link", "mediaType" => data["mediaType"], "href" => data["url"]}]
+        media_type = data["mediaType"] || data["mimeType"]
-        Map.put(data, "url", url)
+        href = data["url"] || data["href"]
+
+        url = [%{"type" => "Link", "mediaType" => media_type, "href" => href}]
+
+        data
+        |> Map.put("mediaType", media_type)
+        |> Map.put("url", url)
       end)
 
     object
@@ -190,7 +196,22 @@ def fix_url(%{"url" => url} = object) when is_map(url) do
     |> Map.put("url", url["href"])
   end
 
-  def fix_url(%{"url" => url} = object) when is_list(url) do
+  def fix_url(%{"type" => "Video", "url" => url} = object) when is_list(url) do
+    first_element = Enum.at(url, 0)
+
+    link_element =
+      url
+      |> Enum.filter(fn x -> is_map(x) end)
+      |> Enum.filter(fn x -> x["mimeType"] == "text/html" end)
+      |> Enum.at(0)
+
+    object
+    |> Map.put("attachment", [first_element])
+    |> Map.put("url", link_element["href"])
+  end
+
+  def fix_url(%{"type" => object_type, "url" => url} = object)
+      when object_type != "Video" and is_list(url) do
     first_element = Enum.at(url, 0)
 
     url_string =
@@ -200,15 +221,9 @@ def fix_url(%{"url" => url} = object) when is_list(url) do
         true -> ""
       end
 
-    if Map.get(object, "type") == "Video" do
-      object
-      |> Map.delete("url")
-      |> Map.put("attachment", url_string)
-    else
     object
     |> Map.put("url", url_string)
   end
-  end
 
   def fix_url(object), do: object
 

test/web/activity_pub/transmogrifier_test.exs

@@ -684,6 +684,36 @@ test "it rejects activities without a valid ID" do
 
       :error = Transmogrifier.handle_incoming(data)
     end
+
+    test "it remaps video URLs as attachments if necessary" do
+      {:ok, object} =
+        ActivityPub.fetch_object_from_id(
+          "https://peertube.moe/videos/watch/df5f464b-be8d-46fb-ad81-2d4c2d1630e3"
+        )
+
+      attachment = %{
+        "type" => "Link",
+        "mediaType" => "video/mp4",
+        "href" =>
+          "https://peertube.moe/static/webseed/df5f464b-be8d-46fb-ad81-2d4c2d1630e3-480.mp4",
+        "mimeType" => "video/mp4",
+        "size" => 5_015_880,
+        "url" => [
+          %{
+            "href" =>
+              "https://peertube.moe/static/webseed/df5f464b-be8d-46fb-ad81-2d4c2d1630e3-480.mp4",
+            "mediaType" => "video/mp4",
+            "type" => "Link"
+          }
+        ],
+        "width" => 480
+      }
+
+      assert object.data["url"] ==
+               "https://peertube.moe/videos/watch/df5f464b-be8d-46fb-ad81-2d4c2d1630e3"
+
+      assert object.data["attachment"] == [attachment]
+    end
   end
 
   describe "prepare outgoing" do