Code Examples

Learn by example with real, working Cortex code

Creating Your First Actor

import { ActorSystem, EventBus } from 'cortex';

const eventBus = EventBus.getInstance();
const actorSystem = new ActorSystem(eventBus);

// Define an actor
class GreeterActor {
  async handle(message: any) {
    console.log(`Hello, ${message.name}!`);
  }
}

// Create and send a message
const greeter = actorSystem.createActor(GreeterActor);
greeter.send({ name: 'Cortex' });

Output:
Hello, Cortex!

Using the Event Bus

import { EventBus } from 'cortex';

const bus = EventBus.getInstance();

// Subscribe to events
bus.on('user:created', (event) => {
  console.log(`User created: ${event.userId}`);
});

// Publish events
bus.emit('user:created', {
  userId: 'user-123',
  email: 'user@example.com'
});

Output:
User created: user-123

Building a REST API

import { CortexHttpServer } from 'cortex';

const server = new CortexHttpServer(3000);

server.get('/api/users/:id', (req, res) => {
  const userId = req.params.id;
  res.writeHead(200, {'Content-Type': 'application/json'});
  res.end(JSON.stringify({
    id: userId,
    name: 'John Doe'
  }));
});

await server.start();
console.log('Server listening on port 3000');

Response:
{"id":"123","name":"John Doe"}

Circuit Breaker Pattern

import { CircuitBreaker } from 'cortex/resilience';

const breaker = new CircuitBreaker({
  threshold: 5,
  timeout: 60000
});

async function unreliableOperation() {
  return breaker.execute(async () => {
    // Your operation here
    return await fetchExternalAPI();
  });
}

Protects against cascading failures through automatic circuit opening

Middleware Stack

const server = new CortexHttpServer(3000);

// Global middleware
server.use((req, res, next) => {
  console.log(`${req.method} ${req.url}`);
  next();
});

// Route with middleware
server.get('/protected',
  authMiddleware,
  loggingMiddleware,
  (req, res) => {
    res.end('Protected endpoint');
  }
);

All requests are logged and authenticated before reaching the handler

Health Checks

import { HealthCheckRegistry } from 'cortex/observability';

const registry = new HealthCheckRegistry();

registry.register('database', async () => {
  return await db.ping();
});

server.registerHealthEndpoint(registry);

// GET /health
// Returns overall system health status

Health Status: UP
Database: UP