Support profile object

[Jiwoon-Kim]

For example, in WordPress, a Profile object could be used to make entities other than the wp_users table — such as a blog page, custom post type, forum, or taxonomy — behave like ActivityPub actors.

mastodon/mastodon#22322

https://www.w3.org/TR/activitypub/#actors
https://www.w3.org/wiki/ActivityPub/Primer/Actors

ActivityPub actors are generally one of the ActivityStreams Actor Types, but they don't have to be. For example, a Profile object might be used as an actor, or a type from an ActivityStreams extension. Actors are retrieved like any other Object in ActivityPub.

• https://www.w3.org/TR/activitystreams-vocabulary/#dfn-profile
• https://www.w3.org/TR/activitystreams-vocabulary/#dfn-describes
• https://www.w3.org/TR/activitystreams-vocabulary/#actor-types
• https://socialhub.activitypub.rocks/t/describes-property-of-profile-object-why-is-this-specified-as-object-only-and-not-uri-or-link/2873/5
• https://meta.discourse.org/t/validate-custom-user-field-for-fediverse-handle/315037

[Jiwoon-Kim]

Exactly — and that’s a very insightful observation.
According to the ActivityPub specification, a Profile object can act as an extension or surrogate of a standard Actor, making it ideal for cases like WordPress, where entities beyond wp_users (such as pages, forums, or taxonomies) can behave as federated actors.
Here’s a structured explanation 👇

---

🧩 1. What is a Profile Object?

Source: ActivityStreams Vocabulary – §5.2 Profile
A Profile is generally defined as:

{
  "type": "Profile",
  "describes": "https://example.com/@username",
  "summary": "My profile for federated blogging"
}

The key idea is that a Profile describes an Actor rather than being one.
It functions as a representation or wrapper for another Actor object.

The describes property is officially defined to accept only an Object, not a URI or Link — although some implementations handle it more flexibly.
See: SocialHub discussion

---

🏗️ 2. Potential Use in WordPress

WordPress treats almost every entity (posts, pages, custom post types, taxonomies, etc.) as a unique Object with its own permalink.
That makes it natural to use a Profile object to make these entities behave like independent ActivityPub actors.

Example — treating a blog page as an actor:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "id": "https://travel-in-busan.com/news/",
  "type": "Profile",
  "describes": {
    "id": "https://travel-in-busan.com/@news",
    "type": "Group",
    "name": "Travel in Busan Newsroom"
  },
  "summary": "Official newsroom of the Travel in Busan blog",
  "icon": "https://travel-in-busan.com/logo.png"
}

→ /news/ can now act as a Group Actor in the Fediverse.
→ The Profile describes the Group, which can publish posts or broadcast announcements.

---

💬 3. Applying It to Forums, Taxonomies, and Custom Post Types

Type	Example URI	Purpose of Profile Object
Forum (CPT)	/forums/travel-tips/	Make a forum behave as a Group Actor that announces new posts
Taxonomy (Category)	/category/busan-culture/	Treat a category as a thematic or topical Actor
Custom Post Type (Organization)	/organization/wordpress-ko/	Represent a project or organization as an Organization Actor
Author Page	/author/kimjiwoon/	Provide an extended profile representation for an existing Person actor

This approach enables federated interactions per content entity, not just per user account.

---

🧠 4. Benefits Summary

1. Flexible Actor Modeling

   • WordPress objects (page, forum, category, etc.) can act as actors

   • Moves beyond user-based ActivityPub models

2. Hierarchical Federation Structure

   • Person → Organization → Group (nested actor relationships)

3. Native Compatibility

   • WordPress already provides unique permalinks, ideal for mapping Profile → Actor

---

⚙️ 5. Implementation Notes

• The Profile.id should point to the permalink of the page or CPT

• The describes property should define a virtual Actor object

• The ActivityPub endpoint may return the Profile when queried

• followers, inbox, and outbox URLs can proxy to or redirect to the described Actor

---

In short:
“Supporting Profile objects in WordPress allows pages, forums, and taxonomies to function as ActivityPub actors — not just users in the wp_users table.”

This aligns perfectly with the spec and mirrors how platforms like Lemmy (community-based) or Threads (topic-based) represent non-user actors.

Exactly — and that’s a very insightful observation. According to the ActivityPub specification, a **Profile object** can act as an **extension or surrogate of a standard Actor**, making it ideal for cases like WordPress, where entities beyond `wp_users` (such as pages, forums, or taxonomies) can behave as federated actors. Here’s a structured explanation 👇

---

🧩 1. What is a Profile Object?

Source: [ActivityStreams Vocabulary – §5.2 Profile](https://www.w3.org/TR/activitystreams-vocabulary/#dfn-profile)
A Profile is generally defined as:

{
  "type": "Profile",
  "describes": "https://example.com/@username",
  "summary": "My profile for federated blogging"
}

The key idea is that a Profile describes an Actor rather than being one.
It functions as a representation or wrapper for another Actor object.

The describes property is officially defined to accept only an Object, not a URI or Link — although some implementations handle it more flexibly.
See: [SocialHub discussion](https://socialhub.activitypub.rocks/t/describes-property-of-profile-object-why-is-this-specified-as-object-only-and-not-uri-or-link/2873/5)

---

🏗️ 2. Potential Use in WordPress

WordPress treats almost every entity (posts, pages, custom post types, taxonomies, etc.) as a unique Object with its own permalink.
That makes it natural to use a Profile object to make these entities behave like independent ActivityPub actors.

Example — treating a blog page as an actor:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "id": "https://travel-in-busan.com/news/",
  "type": "Profile",
  "describes": {
    "id": "https://travel-in-busan.com/@news",
    "type": "Group",
    "name": "Travel in Busan Newsroom"
  },
  "summary": "Official newsroom of the Travel in Busan blog",
  "icon": "https://travel-in-busan.com/logo.png"
}

→ /news/ can now act as a Group Actor in the Fediverse.
→ The Profile describes the Group, which can publish posts or broadcast announcements.

---

💬 3. Applying It to Forums, Taxonomies, and Custom Post Types

Type	Example URI	Purpose of Profile Object
Forum (CPT)	/forums/travel-tips/	Make a forum behave as a Group Actor that announces new posts
Taxonomy (Category)	/category/busan-culture/	Treat a category as a thematic or topical Actor
Custom Post Type (Organization)	/organization/wordpress-ko/	Represent a project or organization as an Organization Actor
Author Page	/author/kimjiwoon/	Provide an extended profile representation for an existing Person actor

This approach enables federated interactions per content entity, not just per user account.

---

🧠 4. Benefits Summary

1. Flexible Actor Modeling

   • WordPress objects (page, forum, category, etc.) can act as actors
   • Moves beyond user-based ActivityPub models

2. Hierarchical Federation Structure

   • Person → Organization → Group (nested actor relationships)

3. Native Compatibility

   • WordPress already provides unique permalinks, ideal for mapping Profile → Actor

---

⚙️ 5. Implementation Notes

• The Profile.id should point to the permalink of the page or CPT
• The describes property should define a virtual Actor object
• The ActivityPub endpoint may return the Profile when queried
• followers, inbox, and outbox URLs can proxy to or redirect to the described Actor

---

In short:
“Supporting Profile objects in WordPress allows pages, forums, and taxonomies to function as ActivityPub actors — not just users in the wp_users table.”

This aligns perfectly with the spec and mirrors how platforms like Lemmy (community-based) or Threads (topic-based) represent non-user actors.