Fix wrongly linkified image urls with markdown AP content

When we get a Markdown source in AP, we prefer that over HTML. Our linkifying of urls however should not be run in this case, we want the markdown to be as it was sent.

Fixes broken images between Socialhome instances.

federation/entities/activitypub/entities.py

@@ -67,6 +67,10 @@ class CleanContentMixin(RawContentMixin):
                 return
             return attrs
 
+        if self._media_type == "text/markdown":
+            # Skip when markdown
+            return
+
         self.raw_content = bleach.linkify(
             self.raw_content,
             callbacks=[remove_tag_links],

federation/tests/entities/activitypub/test_entities.py

@@ -481,6 +481,17 @@ class TestEntitiesPostReceive:
             "public": False,
         }]
 
+    @patch("federation.entities.activitypub.entities.bleach.linkify", autospec=True)
+    def test_post_post_receive__linkifies_if_not_markdown(self, mock_linkify, activitypubpost):
+        activitypubpost._media_type = 'text/html'
+        activitypubpost.post_receive()
+        mock_linkify.assert_called_once()
+
+    @patch("federation.entities.activitypub.entities.bleach.linkify", autospec=True)
+    def test_post_post_receive__skips_linkify_if_markdown(self, mock_linkify, activitypubpost):
+        activitypubpost.post_receive()
+        mock_linkify.assert_not_called()
+
 
 class TestEntitiesPreSend:
     def test_post_inline_images_are_attached(self, activitypubpost_embedded_images):