TagValidator: allow Link tags, don't go nuclear for unrecognized Tag types

lib/pleroma/web/activity_pub/object_validators/tag_validator.ex

@@ -24,6 +24,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.TagValidator do
       field(:url, ObjectValidators.Uri)
     end
 
+    field(:mediaType, ObjectValidators.MIME)
     field(:updated, ObjectValidators.DateTime)
     field(:id, ObjectValidators.Uri)
   end
@@ -68,6 +69,14 @@ def changeset(struct, %{"type" => "Emoji"} = data) do
     |> validate_required([:type, :name, :icon])
   end
 
+  def changeset(struct, %{"type" => "Link"} = data) do
+    struct
+    |> cast(data, [:type, :name, :href, :mediaType])
+  end
+
+  # Fallback
+  def changeset(struct, data), do: cast(struct, data, [:type, :name])
+
   def icon_changeset(struct, data) do
     struct
     |> cast(data, [:type, :url])

test/fixtures/fep-e232.json

@@ -0,0 +1,29 @@
+{
+  "@context": "https://www.w3.org/ns/activitystreams",
+  "id": "https://mitra.social/objects/01839574-d41f-01a7-8eef-abfe0badcd6a",
+  "type": "Note",
+  "attributedTo": "https://mitra.social/users/silverpill",
+  "content": "Quote test<p class=\"inline-quote\">RE: <a href=\"https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749\">https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749</a></p>",
+  "published": "2022-10-01T21:30:05.211215Z",
+  "tag": [
+    {
+      "name": "@silverpill@mitra.social",
+      "type": "Mention",
+      "href": "https://mitra.social/users/silverpill"
+    },
+    {
+      "name": "RE: https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749",
+      "type": "Link",
+      "href": "https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749",
+      "mediaType": "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\""
+    }
+  ],
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public",
+    "https://mitra.social/users/silverpill"
+  ],
+  "cc": [
+    "https://mitra.social/users/silverpill/followers"
+  ],
+  "quoteUrl": "https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749"
+}

test/fixtures/tesla_mock/mitra.social_01830912-1357-d4c5-e4a2-76eab347e749.json

@@ -0,0 +1,14 @@
+{
+  "@context": "https://www.w3.org/ns/activitystreams",
+  "id": "https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749",
+  "type": "Note",
+  "attributedTo": "https://mitra.social/users/silverpill",
+  "content": "FEP-e232 (Object Links) has been accepted into FEP repository:<br>\n<br>\n<a href=\"https://codeberg.org/fediverse/fep/src/branch/main/feps/fep-e232.md\" rel=\"noopener noreferrer\">https://codeberg.org/fediverse/fep/src/branch/main/feps/fep-e232.md</a><br>\n<br>\nThis document has the \"DRAFT\" status. It is not finalized and still can be updated based on the feedback from implementers.",
+  "published": "2022-09-04T15:15:23.095610Z",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://mitra.social/users/silverpill/followers"
+  ]
+}

test/pleroma/web/activity_pub/transmogrifier_test.exs

@@ -130,6 +130,47 @@ test "it accepts quote posts" do
       assert Object.normalize("https://misskey.io/notes/8vs6wxufd0")
     end
 
+    test "it accepts FEP-e232 quote posts" do
+      insert(:user, ap_id: "https://mitra.social/users/silverpill")
+
+      object = File.read!("test/fixtures/fep-e232.json") |> Jason.decode!()
+
+      message = %{
+        "@context" => "https://www.w3.org/ns/activitystreams",
+        "type" => "Create",
+        "actor" => "https://mitra.social/users/silverpill",
+        "object" => object
+      }
+
+      assert {:ok, activity} = Transmogrifier.handle_incoming(message)
+
+      # Object was created in the database
+      object = Object.normalize(activity)
+
+      assert object.data["quoteUrl"] ==
+               "https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749"
+
+      # The Link tag was normalized
+      assert object.data["tag"] == [
+               %{
+                 "href" => "https://mitra.social/users/silverpill",
+                 "name" => "@silverpill@mitra.social",
+                 "type" => "Mention"
+               },
+               %{
+                 "href" => "https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749",
+                 "mediaType" =>
+                   "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"",
+                 "name" =>
+                   "RE: https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749",
+                 "type" => "Link"
+               }
+             ]
+
+      # It fetched the quoted post
+      assert Object.normalize("https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749")
+    end
+
     test "it fixes both the Create and object contexts in a reply" do
       insert(:user, ap_id: "https://mk.absturztau.be/users/8ozbzjs3o8")
       insert(:user, ap_id: "https://p.helene.moe/users/helene")

test/support/http_request_mock.ex

@@ -1389,6 +1389,18 @@ def get("https://misskey.io/notes/8vs6wxufd0", _, _, _) do
      }}
   end
 
+  def get("https://mitra.social/objects/01830912-1357-d4c5-e4a2-76eab347e749", _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body:
+         File.read!(
+           "test/fixtures/tesla_mock/mitra.social_01830912-1357-d4c5-e4a2-76eab347e749.json"
+         ),
+       headers: activitypub_object_headers()
+     }}
+  end
+
   def get("https://gleasonator.com/objects/102eb097-a18b-4cd5-abfc-f952efcb70bb", _, _, _) do
     {:ok,
      %Tesla.Env{