Discourse Comments

WASM-powered embedded comment system for Discourse forums.

Features

• Framework-agnostic web component
• WASM-based Discourse API client
• OAuth authentication via Discourse User API Keys
• Shadow DOM isolation
• TypeScript support

Getting Started

1. Build the component

git clone https://github.com/ducks/discourse-comments.git
cd discourse-comments
npm install
npm run build

2. Configure your Discourse instance

In your Discourse admin panel (/admin/site_settings), configure these settings:

• cors_origins: Add the domain where you'll host the component (e.g., https://your-blog.com)
• user_api_key_allowed_auth_redirects: Add the full URL pattern for OAuth redirects (e.g., https://your-blog.com/*)

3. Create a topic for comments

Create a topic in your Discourse forum that will hold the comments. Note the topic ID from the URL (e.g., /t/my-post-comments/123 has topic ID 123).

4. Add to your page

Copy the dist/ and wasm/ folders to your site, then add:

<script type="module" src="./dist/index.js"></script>

<discourse-comments
  discourse-url="https://your-forum.com"
  topic-id="123">
</discourse-comments>

Development

npm install
npm run build

Open demo.html in a browser to see the component in action.

Requirements

Discourse Version: For authenticated commenting (OAuth login), your Discourse instance must be running a version from December 11, 2025 or later. This is when RSA-OAEP padding support was added for User API Key encryption (PR #36592).

Anonymous comment reading works on any Discourse version.

CORS Configuration: Your Discourse instance needs to allow requests from wherever you host this component. Set cors_origins in site settings.

OAuth Redirect: For login to work, add your demo URL to the allowed user_api_key_allowed_auth_redirects site setting.

Architecture

• src/discourse-comments.ts - Web component implementation
• WASM client from discourse-api-rs