GitLab

Environment

• Installation type (OTP or From Source): From Source
• Pleroma version (could be found in the "Version" tab of settings in Pleroma-FE): 2.4.2
• Elixir version (elixir -v for from source installations, N/A for OTP): Elixir 1.9.1
• Operating system: Ubuntu 20.04.4 LTS
• PostgreSQL version (psql -V): psql (PostgreSQL) 14.2 (Ubuntu 14.2-1.pgdg20.04+1+b1)

Bug description

I have an Owncast instance set up, which will send out notifications to followers (as Create activities with a Note).

I noticed that the notifications will work fine in other ActivityPub implementations, but with Pleroma I receive an "Unhandled Activity" error.

The Pleroma installation was set up with these instructions: https://docs-develop.pleroma.social/backend/installation/debian_based_en/ and is using the stock configuration.

I did notice that in Owncast, if I modify the source to not include an attachment, the activity shows up in follower's timelines. The only striking thing I notice about the Owncast-generated attachment and others - the attachment is a JSON object, but most fediverse things seem to use an array of objects. From reading the specs, I believe this is fine.

So for reference, here's the JSON from an activity that generated the "Unhandled Activity" message - posted to the user's inbox:

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    "http://joinmastodon.org/ns"
  ],
  "actor": "https://owncast.localhost.localdomain/federation/user/streamer",
  "audience": "https://www.w3.org/ns/activitystreams#Public",
  "id": "https://owncast.localhost.localdomain/federation/KCfHuqU7Rz",
  "object": {
    "attachment": {
      "content": "Live stream preview",
      "type": "Image",
      "url": "https://owncast.localhost.localdomain/preview.gif?us=KjfNX387gm"
    },
    "attributedTo": "https://owncast.localhost.localdomain/federation/user/streamer",
    "audience": "https://www.w3.org/ns/activitystreams#Public",
    "content": "<p>I've gone live!</p><p></p><p><a class=\"hashtag\" href=\"https://directory.owncast.online/tags/owncast\">#owncast</a> <a class=\"hashtag\" href=\"https://directory.owncast.online/tags/streaming\">#streaming</a></p><a href=\"https://owncast.localhost.localdomain\">https://owncast.localhost.localdomain</a>",
    "id": "https://owncast.localhost.localdomain/federation/KjBNuq8ng",
    "published": "2022-04-17T15:42:03Z",
    "tag": [
      {
        "href": "https://directory.owncast.online/tags/owncast",
        "name": "#owncast",
        "type": "Hashtag"
      },
      {
        "href": "https://directory.owncast.online/tags/streaming",
        "name": "#streaming",
        "type": "Hashtag"
      },
      {
        "href": "https://directory.owncast.online/tags/owncast",
        "name": "#owncast",
        "type": "Hashtag"
      }
    ],
    "to": "https://www.w3.org/ns/activitystreams#Public",
    "type": "Note"
  },
  "to": "https://www.w3.org/ns/activitystreams#Public",
  "type": "Create"
}

Whereas this JSON works correctly (same as above, just with the attachment property removed:

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    "http://joinmastodon.org/ns"
  ],
  "actor": "https://owncast.localhost.localdomain/federation/user/streamer",
  "audience": "https://www.w3.org/ns/activitystreams#Public",
  "id": "https://owncast.localhost.localdomain/federation/h7S-lqU7gz",
  "object": {
    "attributedTo": "https://owncast.localhost.localdomain/federation/user/streamer",
    "audience": "https://www.w3.org/ns/activitystreams#Public",
    "content": "<p>I've gone live!</p><p></p><p><a class=\"hashtag\" href=\"https://directory.owncast.online/tags/owncast\">#owncast</a> <a class=\"hashtag\" href=\"https://directory.owncast.online/tags/streaming\">#streaming</a></p><a href=\"https://owncast.localhost.localdomain\">https://owncast.localhost.localdomain</a>",
    "id": "https://owncast.localhost.localdomain/federation/2nI-lqUnR",
    "published": "2022-04-17T15:30:21Z",
    "tag": [
      {
        "href": "https://directory.owncast.online/tags/owncast",
        "name": "#owncast",
        "type": "Hashtag"
      },
      {
        "href": "https://directory.owncast.online/tags/streaming",
        "name": "#streaming",
        "type": "Hashtag"
      },
      {
        "href": "https://directory.owncast.online/tags/owncast",
        "name": "#owncast",
        "type": "Hashtag"
      }
    ],
    "to": "https://www.w3.org/ns/activitystreams#Public",
    "type": "Note"
  },
  "to": "https://www.w3.org/ns/activitystreams#Public",
  "type": "Create"
}