Tips

order/created/v1
order/created/v2

order/created
order/created-v2
order/placed  // Renamed for clarity

// v1
{
  "orderId": "123",
  "amount": 99.99
}

// v2 (backward compatible)
{
  "orderId": "123",
  "amount": 99.99,
  "currency": "USD",  // New field
  "tax": 8.99         // New field
}

// ❌ Large payload
{
  "order": { /* full order object */ },
  "customer": { /* full customer object */ },
  "items": [ /* full item objects */ ]
}

// ✅ Lean payload
{
  "orderId": "123",
  "customerId": "456",
  "amount": 99.99
}

subscription.on(async (event) => {
  if (await isProcessed(event.idem)) {
    await event.ack();
    return;
  }
  
  await processEvent(event);
  await markProcessed(event.idem);
  await event.ack();
});

if (event.metadata.$internal?.replay_info?.isReplayed) {
  // This is a replayed event
  // Handle accordingly (e.g., skip side effects)
}

// Service A publishes order/created
await client.publish("order/created", ["service-b"], orderData);

// Service B processes and publishes payment/requested
subscription.on(async (event) => {
  await processOrder(event.payload);
  await client.publish("payment/requested", ["payment-service"], paymentData);
  await event.ack();
});

const batch = [];

subscription.on(async (event) => {
  // Acknowledge immediately to receive next event
  await event.ack();
  
  // Add to batch
  batch.push(event.payload);
  
  // Process batch when ready
  if (batch.length >= 10) {
    await processBatch(batch);
    batch = [];
  }
});

// Worker 1
const client1 = await EnSyncClient.create({ appKey, appSecret });
await client1.subscribe("order/*");

// Worker 2
const client2 = await EnSyncClient.create({ appKey, appSecret });
await client2.subscribe("order/*");

// Worker 3
const client3 = await EnSyncClient.create({ appKey, appSecret });
await client3.subscribe("order/*");

// Each worker processes events independently and in parallel