ActivityPub Plugin

Plugin
,
307

Hi there :wave:
First of all, thanks for the impressive work that has one into making this happen. I couldn’t be happier of the decision to move our community to Discourse thanks to this.

I added the plugin to our instance and configured one actor. However, when I post in a category with an actor associated, I get a “Internal Server Error”. I couldn’t find much in the logs other than the request failed with a 500 error:

[no timestamp]  by PostsController#create as JSON
[no timestamp]  Parameters: {"raw"=>"This is just a test test test", "title"=>"This is just a test test test", "unlist_topic"=>"false", "category"=>"10", "is_warning"=>"false", "archetype"=>"regular", "typing_duration_msecs"=>"200", "composer_open_duration_msecs"=>"3160", "shared_draft"=>"false", "draft_key"=>"new_topic", "activity_pub_visibility"=>"public", "nested_post"=>"true"}
Sep 25 15:06:38 - Processing by PostsController#create as JSON
Sep 25 15:06:38 - Parameters: {"raw"=>"This is just a test test test", "title"=>"This is just a test test test", "unlist_topic"=>"false", "category"=>"10", "is_warning"=>"false", "archetype"=>"regular", "typing_duration_msecs"=>"200", "composer_open_duration_msecs"=>"3160", "shared_draft"=>"false", "draft_key"=>"new_topic", "activity_pub_visibility"=>"public", "nested_post"=>"true"}
Sep 25 15:06:38 - 172.18.0.1 - - [25/Sep/2024:13:06:38 +0000] "POST /message-bus/3e2e0add2e9a41cc9ce7041980fe4f81/poll HTTP/1.1" 200 2438 "https://community.tuist.io/c/announcements/10" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:130.0) Gecko/20100101 Firefox/130.0"
Sep 25 15:06:38 - 172.18.0.1 - - [25/Sep/2024:13:06:38 +0000] "POST /message-bus/3e2e0add2e9a41cc9ce7041980fe4f81/poll HTTP/1.1" 200 115 "https://community.tuist.io/c/announcements/10" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:130.0) Gecko/20100101 Firefox/130.0"
[no timestamp]  2024-09-25T13:06:38Z cloudron 37a832f8-20ab-41d7-9d4d-82052354c0eb 1101 37a832f8-20ab-41d7-9d4d-82052354c0eb - 172.18.0.1 - - [25/Sep/2024:13:06:38 +0000] "POST /message-bus/3e2e0add2e9a41cc9ce7041980fe4f81/poll HTTP/1.1" 200 115 "https://community.tuist.io/c/announcements/10" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:130.0) Gecko/20100101 Firefox/130.0"
[no timestamp]  start
Sep 25 15:06:39 - start
[no timestamp]  start
Sep 25 15:06:39 - start
[no timestamp]  done
Sep 25 15:06:39 - done
[no timestamp]  start
Sep 25 15:06:39 - start
[no timestamp]  start
[no timestamp]  start
Sep 25 15:06:39 - start
Sep 25 15:06:39 - start
[no timestamp]  done
Sep 25 15:06:39 - done
[no timestamp]  done
Sep 25 15:06:39 - done
[no timestamp]  500 Internal Server Error in 476ms (ActiveRecord: 0.0ms | Allocations: 56364)
[no timestamp]  done
Sep 25 15:06:39 - Completed 500 Internal Server Error in 476ms (ActiveRecord: 0.0ms | Allocations: 56364)
Sep 25 15:06:39 - done
Sep 25 15:06:39 - 172.18.0.1 - - [25/Sep/2024:13:06:39 +0000] "POST /posts HTTP/1.1" 500 46 "https://community.tuist.io/c/announcements/10" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:130.0) Gecko/20100101 Firefox/130.0"
[no timestamp]  start
Sep 25 15:06:39 - start
[no timestamp]  done
Sep 25 15:06:39 - done
[no timestamp]  done
Sep 25 15:06:39 - done

What’s the recommended path to debug this issue?

308

Next step is to go to /logs on your forum, find the corresponding log line and post the stack trace here.

3 Likes
309

Here’s the error:

Message

NoMethodError (undefined method `moderating_groups' for #<Category id: 10, name: "Announcements", color: "652D90", topic_id: 55, topic_count: 5, created_at: "2024-09-25 09:23:28.181772000 +0000", updated_at: "2024-09-27 11:53:47.131692000 +0000", user_id: 3, topics_year: 4, topics_month: 4, topics_week: 4, slug: "announcements", description: "This category is used for announcements by the mai...", text_color: "FFFFFF", read_restricted: false, auto_close_hours: nil, post_count: 4, latest_post_id: 108, latest_topic_id: 83, position: 7, parent_category_id: nil, posts_year: 4, posts_month: 4, posts_week: 4, email_in: nil, email_in_allow_strangers: false, topics_day: 0, posts_day: 0, allow_badges: true, name_lower: "announcements", auto_close_based_on_last_post: false, topic_template: nil, contains_messages: nil, sort_order: nil, sort_ascending: nil, uploaded_logo_id: nil, uploaded_background_id: nil, topic_featured_link_allowed: true, all_topics_wiki: false, show_subcategory_list: false, num_featured_topics: 3, default_view: nil, subcategory_list_style: "rows_with_featured_topics", default_top_period: "all", mailinglist_mirror: false, minimum_required_tags: 0, navigate_to_first_post_after_read: false, search_priority: 0, allow_global_tags: false, reviewable_by_group_id: nil, read_only_banner: nil, default_list_filter: "all", allow_unlimited_owner_edits_on_first_post: false, default_slow_mode_seconds: nil, uploaded_logo_dark_id: nil, uploaded_background_dark_id: nil>)
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
lib/plugin/instance.rb:576:in `block in on'
lib/discourse_event.rb:12:in `bl...

Backtrace

activemodel (7.1.3.4) lib/active_model/attribute_methods.rb:489:in `method_missing'
plugins/discourse-activity-pub/plugin.rb:367:in `block (2 levels) in activate!'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
plugins/discourse-activity-pub/plugin.rb:331:in `block (2 levels) in activate!'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
plugins/discourse-activity-pub/plugin.rb:337:in `block (2 levels) in activate!'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
plugins/discourse-activity-pub/app/models/discourse_activity_pub_object.rb:99:in `after_scheduled'
plugins/discourse-activity-pub/app/models/discourse_activity_pub_activity.rb:109:in `after_scheduled'
plugins/discourse-activity-pub/lib/discourse_activity_pub/delivery_handler.rb:89:in `after_scheduled'
plugins/discourse-activity-pub/lib/discourse_activity_pub/delivery_handler.rb:15:in `perform'
plugins/discourse-activity-pub/lib/discourse_activity_pub/delivery_handler.rb:27:in `perform'
plugins/discourse-activity-pub/app/models/concerns/discourse_activity_pub/ap/model_callbacks.rb:160:in `block in activity_pub_deliver_activity'
plugins/discourse-activity-pub/app/models/concerns/discourse_activity_pub/ap/model_callbacks.rb:159:in `each'
plugins/discourse-activity-pub/app/models/concerns/discourse_activity_pub/ap/model_callbacks.rb:159:in `activity_pub_deliver_activity'
plugins/discourse-activity-pub/app/models/concerns/discourse_activity_pub/ap/model_callbacks.rb:41:in `perform_activity_pub_activity'
plugins/discourse-activity-pub/plugin.rb:455:in `block (2 levels) in activate!'
lib/plugin/instance.rb:376:in `public_send'
lib/plugin/instance.rb:376:in `block (2 levels) in add_to_class'
plugins/discourse-activity-pub/plugin.rb:661:in `block (2 levels) in activate!'
lib/plugin/instance.rb:576:in `block in on'
lib/discourse_event.rb:12:in `block in trigger'
/home/cloudron/rbenv/versions/3.2.2/lib/ruby/3.2.0/set.rb:511:in `each_key'
/home/cloudron/rbenv/versions/3.2.2/lib/ruby/3.2.0/set.rb:511:in `each'
lib/discourse_event.rb:12:in `trigger'
lib/post_creator.rb:258:in `trigger_after_events'
lib/post_creator.rb:220:in `create'
lib/new_post_manager.rb:318:in `perform_create_post'
lib/new_post_manager.rb:252:in `perform'
app/controllers/posts_controller.rb:215:in `create'
actionpack (7.1.3.4) lib/action_controller/metal/basic_implicit_render.rb:6:in `send_action'
actionpack (7.1.3.4) lib/abstract_controller/base.rb:224:in `process_action'
actionpack (7.1.3.4) lib/action_controller/metal/rendering.rb:165:in `process_action'
actionpack (7.1.3.4) lib/abstract_controller/callbacks.rb:259:in `block in process_action'
activesupport (7.1.3.4) lib/active_support/callbacks.rb:121:in `block in run_callbacks'
app/controllers/application_controller.rb:424:in `block in with_resolved_locale'
i18n (1.14.5) lib/i18n.rb:351:in `with_locale'
app/controllers/application_controller.rb:424:in `with_resolved_locale'
activesupport (7.1.3.4) lib/active_support/callbacks.rb:130:in `block in run_callbacks'
activesupport (7.1.3.4) lib/active_support/callbacks.rb:141:in `run_callbacks'
actionpack (7.1.3.4) lib/abstract_controller/callbacks.rb:258:in `process_action'
actionpack (7.1.3.4) lib/action_controller/metal/rescue.rb:25:in `process_action'
actionpack (7.1.3.4) lib/action_controller/metal/instrumentation.rb:74:in `block in process_action'
activesupport (7.1.3.4) lib/active_support/notifications.rb:206:in `block in instrument'
activesupport (7.1.3.4) lib/active_support/notifications/instrumenter.rb:58:in `instrument'
activesupport (7.1.3.4) lib/active_support/notifications.rb:206:in `instrument'
actionpack (7.1.3.4) lib/action_controller/metal/instrumentation.rb:73:in `process_action'
actionpack (7.1.3.4) lib/action_controller/metal/params_wrapper.rb:261:in `process_action'
activerecord (7.1.3.4) lib/active_record/railties/controller_runtime.rb:32:in `process_action'
actionpack (7.1.3.4) lib/abstract_controller/base.rb:160:in `process'
actionview (7.1.3.4) lib/action_view/rendering.rb:40:in `process'
rack-mini-profiler (3.3.1) lib/mini_profiler/profiling_methods.rb:89:in `block in profile_method'
actionpack (7.1.3.4) lib/action_controller/metal.rb:227:in `dispatch'
actionpack (7.1.3.4) lib/action_controller/metal.rb:309:in `dispatch'
actionpack (7.1.3.4) lib/action_dispatch/routing/route_set.rb:49:in `dispatch'
actionpack (7.1.3.4) lib/action_dispatch/routing/route_set.rb:32:in `serve'
actionpack (7.1.3.4) lib/action_dispatch/journey/router.rb:51:in `block in serve'
actionpack (7.1.3.4) lib/action_dispatch/journey/router.rb:131:in `block in find_routes'
actionpack (7.1.3.4) lib/action_dispatch/journey/router.rb:124:in `each'
actionpack (7.1.3.4) lib/action_dispatch/journey/router.rb:124:in `find_routes'
actionpack (7.1.3.4) lib/action_dispatch/journey/router.rb:32:in `serve'
actionpack (7.1.3.4) lib/action_dispatch/routing/route_set.rb:882:in `call'
lib/middleware/omniauth_bypass_middleware.rb:64:in `call'
rack (2.2.9) lib/rack/tempfile_reaper.rb:15:in `call'
rack (2.2.9) lib/rack/conditional_get.rb:40:in `call'
rack (2.2.9) lib/rack/head.rb:12:in `call'
actionpack (7.1.3.4) lib/action_dispatch/http/permissions_policy.rb:36:in `call'
lib/content_security_policy/middleware.rb:12:in `call'
lib/middleware/anonymous_cache.rb:393:in `call'
lib/middleware/csp_script_nonce_injector.rb:12:in `call'
config/initializers/008-rack-cors.rb:14:in `call'
rack (2.2.9) lib/rack/session/abstract/id.rb:266:in `context'
rack (2.2.9) lib/rack/session/abstract/id.rb:260:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/cookies.rb:689:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (7.1.3.4) lib/active_support/callbacks.rb:101:in `run_callbacks'
actionpack (7.1.3.4) lib/action_dispatch/middleware/callbacks.rb:28:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/debug_exceptions.rb:29:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
logster (2.20.0) lib/logster/middleware/reporter.rb:40:in `call'
lib/freedom_patches/rails_rack_logger_from_rails_7_2.rb:35:in `call_app'
lib/freedom_patches/rails_rack_logger_from_rails_7_2.rb:22:in `call'
config/initializers/100-quiet_logger.rb:20:in `call'
config/initializers/100-silence_logger.rb:29:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/request_id.rb:28:in `call'
lib/middleware/enforce_hostname.rb:24:in `call'
rack (2.2.9) lib/rack/method_override.rb:24:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/executor.rb:14:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/static.rb:25:in `call'
rack (2.2.9) lib/rack/sendfile.rb:110:in `call'
rack-mini-profiler (3.3.1) lib/mini_profiler.rb:191:in `call'
message_bus (4.3.8) lib/message_bus/rack/middleware.rb:60:in `call'
lib/middleware/request_tracker.rb:360:in `call'
actionpack (7.1.3.4) lib/action_dispatch/middleware/remote_ip.rb:92:in `call'
railties (7.1.3.4) lib/rails/engine.rb:536:in `call'
railties (7.1.3.4) lib/rails/railtie.rb:226:in `public_send'
railties (7.1.3.4) lib/rails/railtie.rb:226:in `method_missing'
rack (2.2.9) lib/rack/urlmap.rb:74:in `block in call'
rack (2.2.9) lib/rack/urlmap.rb:58:in `each'
rack (2.2.9) lib/rack/urlmap.rb:58:in `call'
unicorn (6.1.0) lib/unicorn/http_server.rb:634:in `process_client'
unicorn (6.1.0) lib/unicorn/http_server.rb:739:in `worker_loop'
unicorn (6.1.0) lib/unicorn/http_server.rb:547:in `spawn_missing_workers'
unicorn (6.1.0) lib/unicorn/http_ser

Env

HTTP HOSTS: community.tuist.io
311

Hey they, I’m the admin of lemmy.dbzer0.com and I would love to see greater interaction between lemmy and discourse as it feels these two pieces fit together much more natively than discourse and mastodon.

I am primarily interested in a way for lemmy users to be able to see and interact with topics without having to create new accounts for each discourse forum.

From what I understand the biggest problem is that the apub plugin doesn’t represent the discourse categories as apub groups which prevent lemmy from seeing them, right?

Anyway, I want to make myself available, in case you want to have access to a lemmy instance and an admin to test with. My account on lemmy is https://lemmy.dbzer0.com/u/db0

5 Likes
312

Hey guys, I’ll be back providing regular support to this plugin from now until at least March of next year. If you’ve been using this plugin and are struggling in some way, please let me know! I will respond to as many outstanding questions as I can.

Every user in Discourse is in an Actor. The following process in Discourse works the same as it does in Lemmy, and as detailed further in FEP-1b12. The reason you can’t follow Discourse Actors yet (i.e. that the primary focus has been on following categories) is because forums are inherently topic-centric, i.e. discussions that inherently involve multiple users. Indeed, this is the approach that has been taken by other forum-style ActivityPub applications, and is what we’ve been working on in the W3C Forum and Threaded Discussion task force (along with NodeBB and similar software).

What you’re describing is the difference between “First Post Only” and “Full Topic” federation. What you’re expecting is how “Full Topic” federation works. Please see the documentation and instructional videos on this here.

This error means that you’re not running an up-to-date version of Discourse. The ActivityPub plugin currently requires the latest version of Discourse to work.

No, the ActivityPub plugin complies fully with FEP-1b12, which was written by Nutomic (the creator of Lemmy) to describe Group-based federation. Have you tried to federate between Lemmy and Discourse?

2 Likes
313

Are you able to investigate meta not correctly showing my domain and not showing my any content from meta?

1 Like
314

Is there a discourse server with this plugin with which we can test? I’m assuming this forum doesn’t use it, yes?

1 Like
315

Meta does use activitypub, e.g. this topic wasn’t federated:

The image shows a computer screen displaying a user interface of a web-based software application. The software appears to be related to discourse or content analysis, and the user is in the process of selecting a feature or option from the interface. (Captioned by AI)
The image shows a computer screen displaying a user interface of a web-based software application. The software appears to be related to discourse or content analysis, and the user is in the process of selecting a feature or option from the interface. (Captioned by AI)1366×768 71 KB

And this one was:

This is a screenshot of a web development dashboard displaying a user interface with a note in the ActivityPub section. (Captioned by AI)
This is a screenshot of a web development dashboard displaying a user interface with a note in the ActivityPub section. (Captioned by AI)1366×768 93.3 KB

316

Where can I see this info? Also the second link is not available to me

This image displays a plain white background with a block of text. (Captioned by AI)
This image displays a plain white background with a block of text. (Captioned by AI)907×166 10.2 KB

317

The URL (as opposed to the AP uri) for that page is

You can see the AP info by clicking on the AP icon.

Screenshot at Oct 09 15-59-17
Screenshot at Oct 09 15-59-171578×648 107 KB

1 Like
318

I’m struggling to find even a single Apub topic. Mostly the icon doesn’t exist

This is a screenshot of a user interface showing a conversation between a user named Yavu and a bot. The conversation is about typing in the users' search window. (Captioned by AI)
This is a screenshot of a user interface showing a conversation between a user named Yavu and a bot. The conversation is about typing in the users' search window. (Captioned by AI)810×405 43.9 KB

And if it exists, it’s disabled.

Nevertheless, I followed the link you posted and searched for the URL in lemmy (which is how one would retrieve links which had not been previously subscribed to) and it cannot be found. I also cannot find the announcement forum at all so I can subscribe to it

1 Like
319

OK, I managed to find it by searching for it as announcements@meta.discourse.org and subscribed to it. I’m going to try to subscribe to a few other topics to see if I can see new posts in lemmy.

EDIT: Some communities are findable like Feature and Announcements, but Support, Plugin and Bug cannot be found https://lemmy.dbzer0.com/search?q=!plugin%40meta.discourse.org&type=Communities&listingType=All&page=1&sort=TopAll

2 Likes
320

That’s because they don’t have Actors. Please check out the documentation and the instructional videos. You’ll see that each Category needs to be given an Actor before it is findable.

On meta, I think it’s just Announcements and Feature that have had Actors created for them.

4 Likes
321

But I’m an external instance trying get federated content from you. I don’t have visibility to that, do I?

EDIT: Oh I see the federation tab now, but only sometimes. Other times it doesn’t appear

This image is a screenshot of a section of a webpage, specifically showing a red banner with the title "Announcements" and a placeholder for all Discourse announcements. (Captioned by AI)
This image is a screenshot of a section of a webpage, specifically showing a red banner with the title "Announcements" and a placeholder for all Discourse announcements. (Captioned by AI)1189×630 50.4 KB

2 Likes
322

Yes, that’ll be addressed soon. If you don’t see it, just refresh the page and it’ll appear. Let me know how you get on.

Just a note that @mcdanlj and I are discussing this privately. It is likely an historical issue (i.e. because Michael was an early adopter).

4 Likes
323

Yes two questions:

  1. What about not being able to find an existing federated thread like https://meta.discourse.org/ap/object/235d597a789c305cef86318ef84d8762? I tried searching for it on lemmy but it won’t appear.
  2. Why are some threads in a topic federated, but others not? How can I tell?

Anyway, maybe Following an ActivityPub Actor can also be updated for some lemmy-related info?

1 Like
324

You could ask both Lemmy developers and @angus at Lemmy - SocialHub so they can coordinate better. Interop with Lemmy would be :tada:

@angus, in a recent Mastodon blog article there’s something worth implementing, e.g., for the featured topic in a user’s profile, if that topic was started by this user:

We’ve decided to create a new kind of OpenGraph tag—the same kind of tags you have on your website to determine which thumbnail image will appear on the preview for the page when shared on Discord, iMessage, or Mastodon. It looks like this: <meta name="fediverse:creator" content="@Gargron@mastodon.social" />.

The meta tag would appear on the topic, so that Mastodon can link to the user’s profile. I know that there’s no user actor in Discourse, but if the ActivityPub actor is, say, a publishing company, and the topic is about their catalogue, then the use-case makes sense. :wink:

1 Like
325

Yes, as @hellekin suggests, I think a more in-depth Lemmy / Discourse discussion would best be handled here

As I’m resuming work on this plugin, please post your more detailed Lemmy questions there and I’ll follow up soon.

Thanks, I’ll have a think about it.

There are User Actors in Discourse. You just can’t follow them (currently). As this misconception has come up three times today already, I’m thinking of surfacing this somewhere in the UI. In answer to the follow up question “Why can’t you follow user actors if they exist?”, the prior question of “Why would you want to follow user actors in Discourse?” needs to be answered first (i.e. what’s a real use case).

(I am aware that Discourse Follow exists - I built it - however there’s a difference between following a user within an instance for notification/discovery purposes and following a User Actor in the fediverse)

4 Likes
326

This will be fixed once this is merged.

Note also that I’ll be writing a Lemmy <> Discourse “how to” topic here on meta with an instructional video soon. If you’re using, or want to use, Lemmy to federate with Discourse please add your thoughts / experiences here and I’ll make sure to address them in the instructions.

https://socialhub.activitypub.rocks/t/lemmy-discourse-federation/4177

2 Likes
327

Oh, nice change that just landed:

:tada:

3 Likes