Peer Discovery Example

This example demonstrates peer discovery and health management in UNRDF Federation.

Features

• Peer Registration: Register multiple federation peers with metadata
• Health Checks: Ping peers to verify availability
• Status Management: Track peer health (healthy, degraded, unreachable)
• Peer Discovery: List and filter peers by status
• Dynamic Updates: Update peer information and status

Usage

# Install dependencies
pnpm install

# Run the example
pnpm start

# Run tests
pnpm test

Example Code

import { createPeerManager } from '@unrdf/federation';

// Create peer manager
const peerManager = createPeerManager();

// Register peers
peerManager.registerPeer('peer-1', 'http://localhost:8001/sparql', {
  region: 'us-west',
  dataset: 'movies',
});

// List all peers
const peers = peerManager.listPeers();

// Check peer health
const isHealthy = await peerManager.ping('peer-1');

// Filter by status
const healthyPeers = peerManager.listPeers({ status: 'healthy' });

// Update peer status
peerManager.updateStatus('peer-1', 'degraded');

API

Register Peer

const peer = peerManager.registerPeer(id, endpoint, metadata);

List Peers

const allPeers = peerManager.listPeers();
const healthyPeers = peerManager.listPeers({ status: 'healthy' });

Check Health

const isHealthy = await peerManager.ping(id, timeout);

Update Status

peerManager.updateStatus(id, 'healthy' | 'degraded' | 'unreachable');

Get Peer Info

const peer = peerManager.getPeer(id);

Remove Peer

peerManager.unregisterPeer(id);

Status Types

• healthy: Peer is responding to health checks
• degraded: Peer responded but with errors
• unreachable: Peer did not respond to health check

Metadata

Peers can store arbitrary metadata for routing decisions:

{
  region: 'us-west',
  dataset: 'movies',
  version: '2.0',
  capabilities: ['sparql', 'graphql']
}

Learn More

• Federation Documentation
• Distributed Queries Example
• UNRDF Core

Testing

Run the test suite:

pnpm test

Run tests in watch mode:

pnpm test:watch

Generate coverage report:

pnpm test:coverage

Test coverage: 80%+ (minimum requirement)