import { send } from '@vercel/queue';

const { messageId } = await send('order-events', {
  orderId: '123',
  action: 'created',
}, {
  delaySeconds: 30,              // delay before visible
  idempotencyKey: 'order-123',   // deduplication (full retention window)
  retentionSeconds: 3600,        // message TTL (default: 86400 = 24h)
  headers: { 'x-trace-id': 'abc' },
});

// app/api/queues/fulfill-order/route.ts
import { handleCallback } from '@vercel/queue';

export const POST = handleCallback(
  async (message, metadata) => {
    // metadata: { messageId, deliveryCount, createdAt, expiresAt, topicName, consumerGroup, region }
    await processOrder(message);
    // Return normally = acknowledge
    // Throw = retry with backoff
  },
  {
    visibilityTimeoutSeconds: 600, // lease duration (default 300s, auto-extended by SDK)
    retry: (error, metadata) => {
      if (metadata.deliveryCount > 5) return { acknowledge: true }; // give up
      const delay = Math.min(300, 2 ** metadata.deliveryCount * 5);
      return { afterSeconds: delay };
    },
  },
);

{
  "functions": {
    "app/api/queues/fulfill-order/route.ts": {
      "experimentalTriggers": [{
        "type": "queue/v2beta",
        "topic": "order-events",
        "retryAfterSeconds": 60,
        "initialDelaySeconds": 0
      }]
    }
  }
}

import { PollingQueueClient } from '@vercel/queue';

const { receive } = new PollingQueueClient({ region: 'iad1' });

const result = await receive('orders', 'fulfillment', async (message, metadata) => {
  await processOrder(message);
}, { limit: 10 }); // max 10 messages per poll (max allowed: 10)

if (!result.ok && result.reason === 'empty') {
  // No messages available
}

import { QueueClient } from '@vercel/queue';

const queue = new QueueClient({ region: 'sfo1' });
export const { send, handleCallback } = queue;

import { QueueClient, BufferTransport, StreamTransport } from '@vercel/queue';