ActivityWiki

Integrate your MediaWiki instance with the Fediverse via ActivityPub.

Overview

ActivityWiki is a MediaWiki extension that enables wiki instances to participate in the Fediverse by implementing the ActivityPub protocol. This allows:

• Share wiki activity: Article creation and modifications are broadcast to the Fediverse
• User attribution: Track which user made edits and attribute contributions accurately
• Discoverability: Make your wiki discoverable to Mastodon, Pixelfed, and other ActivityPub-compatible platforms
• Federation: Connect your wiki with other federated services

Features

Current (Phase 1)

• ✅ Wiki actor profile (ActivityPub compatible)
• ✅ Activity creation for page edits (Create/Update)
• ✅ REST API endpoints for ActivityPub discovery
• ✅ Activity logging and storage
• ✅ Configuration management

Planned (Phase 2+)

• 🔄 HTTP signature delivery to follower inboxes
• 🔄 Receive Follow/Unfollow requests
• 🔄 Per-user ActivityPub actor profiles
• 🔄 Inbox endpoint for incoming activities

Requirements

• MediaWiki 1.35 or later
• PHP 7.2 or later
• Database: MySQL/MariaDB or PostgreSQL
• HTTP access to external Fediverse servers (for Phase 2+)

Installation

1. Clone the extension

cd /path/to/your/mediawiki/extensions
git clone https://github.com/lucamauri/ActivityWiki.git ActivityWiki
cd ActivityWiki

2. Add to LocalSettings.php

// Enable ActivityWiki extension
wfLoadExtension( 'ActivityWiki' );

// Configuration (optional)
$wgActivityPubEnabled = true;
$wgActivityPubActorName = 'MyWiki';  // Display name in Fediverse
$wgActivityPubEnableUserActors = false;  // Per-user actors (Phase 3)

3. Run database setup

php maintenance/run.php update.php

This creates the necessary database tables.

4. Verify installation

Visit: https://your-wiki.example.com/api/rest_v1/activitypub/actor

You should see a JSON ActivityPub actor profile.

Configuration

Basic Settings (LocalSettings.php)

// Enable/disable the extension
$wgActivityPubEnabled = true;

// How the wiki appears in the Fediverse
$wgActivityPubActorName = 'My Wiki';

// Optional: Enable per-user ActivityPub actors
$wgActivityPubEnableUserActors = false;

// Optional: Exclude certain namespaces from federation
$wgActivityPubExcludedNamespaces = [ NS_TEMPLATE, NS_CATEGORY ];

// Optional: Exclude bot edits from ActivityPub feed
$wgActivityPubExcludeBots = true;

// Optional: Exclude minor edits
$wgActivityPubExcludeMinor = false;

API Endpoints

Once installed, the following ActivityPub endpoints become available:

Actor Profile

GET /api/rest_v1/activitypub/actor

Returns the wiki's ActivityPub actor profile (Service type).

Response:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "id": "https://your-wiki.example.com/api/rest_v1/activitypub/actor",
  "type": "Service",
  "name": "My Wiki",
  "preferredUsername": "mywiki",
  "inbox": "https://your-wiki.example.com/api/rest_v1/activitypub/inbox",
  "outbox": "https://your-wiki.example.com/api/rest_v1/activitypub/outbox",
  "followers": "https://your-wiki.example.com/api/rest_v1/activitypub/followers",
  "publicKey": { ... },
  "summary": "The My Wiki wiki"
}

Activity Outbox

GET /api/rest_v1/activitypub/outbox?limit=10&page=1

Returns paginated list of activities (Create/Update).

Followers

GET /api/rest_v1/activitypub/followers

Returns list of Fediverse accounts following your wiki.

Usage

Following Your Wiki

1. Open your Fediverse client (Mastodon, Pixelfed, etc.)
2. Search for: @yourwikiname@your-wiki.example.com
3. Click Follow
4. When users edit articles, activities appear in your Fediverse feed

Example Activity

When a user edits an article, an Activity is created:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "actor": "https://your-wiki.example.com/api/rest_v1/activitypub/actor",
  "object": {
    "type": "Article",
    "name": "Example Article",
    "url": "https://your-wiki.example.com/wiki/Example_Article",
    "content": "Article content...",
    "attributedTo": "https://your-wiki.example.com/api/rest_v1/activitypub/actor"
  },
  "published": "2025-12-08T22:17:00Z"
}

Development

Repository Structure

ActivityWiki/
├── extension.json           # Extension metadata
├── README.md               # This file
├── includes/
│   ├── Hooks.php           # MediaWiki hook handlers
│   ├── ActivityBuilder.php  # Build ActivityPub JSON
│   ├── DeliveryQueue.php    # Queue activities
│   ├── Api/
│   │   └── ActivityPubModule.php  # REST endpoints
│   └── Jobs/
│       └── DeliveryJob.php  # Async delivery job
├── db/
│   └── tables.sql          # Database schema
└── tests/
    └── phpunit/            # Unit tests

Running Tests

cd /path/to/mediawiki
php tests/phpunit/phpunit.php extensions/ActivityWiki/tests

Code Style

This extension follows MediaWiki coding standards:

• PSR-12 for PHP
• 4-space indentation
• No trailing whitespace

Contributing

We welcome contributions! Please:

1. Fork the repository
2. Create a feature branch (git checkout -b feature/my-feature)
3. Commit changes (git commit -m 'Add my feature')
4. Push to the branch (git push origin feature/my-feature)
5. Open a Pull Request

Please ensure:

• Code follows MediaWiki standards
• Tests pass
• Commits are descriptive

See CONTRIBUTING.md for detailed guidelines.

Roadmap

Phase 1: Activity Broadcasting (Current)

• Hook into page saves
• Build ActivityPub activities
• Store activities in database
• Expose REST API endpoints
• Testing on real wiki

Phase 2: HTTP Delivery

• HTTP signature implementation
• POST activities to follower inboxes
• Retry logic for failed deliveries
• Request queuing and rate limiting

Phase 3: Per-User Actors

• User profile endpoints
• Per-user activity attribution
• User preferences for federation

Phase 4: Inbox & Interactions

• POST /inbox endpoint
• Handle Follow/Unfollow requests
• Track followers
• (Future: Handle replies, likes, etc.)

Security Considerations

• HTTP Signatures: Phase 2 will implement RFC 8017 to sign outgoing requests
• Content Sanitization: Page content is sanitized before inclusion in activities
• Rate Limiting: Configuration options prevent spamming followers
• Private Key Storage: Private keys stored securely in LocalSettings.php
• Access Control: Only public wiki content is federated

Troubleshooting

Activities not appearing in the Fediverse

1. Verify the extension is enabled:

   curl https://your-wiki.example.com/api/rest_v1/activitypub/actor

   Should return actor JSON, not 404.

2. Check MediaWiki error logs:

   tail -f /path/to/mediawiki/logs/debug.log | grep -i activitypub

3. Verify REST API is enabled in LocalSettings.php:

   $wgEnableRestAPI = true;

"No public key found"

1. Generate key pair (will be automatic in v0.2)
2. Verify keys are in database

License

GPL-3.0-or-later

This extension is licensed under the GNU General Public License v3.0 or later. See LICENSE file for details.

Support

• Issues: Report bugs on GitHub Issues
• Discussions: Ask questions on GitHub Discussions
• Documentation: Full docs at mediawiki.org

References

• ActivityPub Specification
• MediaWiki Extension Development
• Fediverse Overview

Acknowledgments

Inspired by XWiki's ActivityPub implementation and the need for federation in wiki communities.

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Created for WikiTrek and the broader MediaWiki community.