implement-queue

Set up queue processing with Cloudflare Queues for asynchronous task handling.

Overview

The implement-queue command creates a complete queue processing system using Cloudflare Queues, enabling reliable asynchronous task processing with automatic retries and dead letter queues.

Usage

/template implement-queue <queue-name> [options]

Parameters

• <queue-name> - Name of the queue to implement (e.g., email-queue, image-processing)

Options

• --max-retries - Maximum retry attempts (default: 3)
• --batch-size - Number of messages to process in batch (default: 10)
• --visibility-timeout - Message visibility timeout in seconds (default: 30)

Examples

Basic Queue

/template implement-queue notification-queue

Image Processing Queue

/template implement-queue image-processing --batch-size 5 --visibility-timeout 300

Email Queue with High Retries

/template implement-queue email-queue --max-retries 5

What It Creates

Queue Configuration

• wrangler.toml queue binding
• Queue consumer worker
• Message producer utilities
• Dead letter queue setup

Generated Structure

src/
├── queues/
│   ├── [queue-name]/
│   │   ├── consumer.ts    # Queue consumer logic
│   │   ├── producer.ts    # Message producer utility
│   │   ├── types.ts       # Queue message types
│   │   └── handler.ts     # Message processing logic
│   └── index.ts           # Queue exports

Example Consumer

// src/queues/email-queue/consumer.ts
export async function handleEmailQueue(batch: MessageBatch<EmailMessage>) {
  for (const message of batch.messages) {
    try {
      await processEmail(message.body);
      message.ack();
    } catch (error) {
      message.retry();
    }
  }
}

Example Producer

// src/queues/email-queue/producer.ts
export async function sendToEmailQueue(env: Env, email: EmailMessage) {
  await env.EMAIL_QUEUE.send(email);
}

Best Practices

1. Idempotent Processing: Ensure messages can be processed multiple times safely
2. Error Handling: Implement proper retry logic
3. Monitoring: Add logging and metrics
4. Batch Processing: Use batching for efficiency
5. Timeouts: Set appropriate visibility timeouts

Common Patterns

With R2 Storage

/template add-r2-storage uploads
/template implement-queue file-processing

With Scheduled Jobs

/template implement-queue cleanup-queue
/template add-worker-cron cleanup-trigger "0 * * * *"

Multi-Stage Processing

/template implement-queue upload-queue
/template implement-queue processing-queue
/template implement-queue notification-queue

Integration Points

• Workers KV: For job status tracking
• R2: For file processing queues
• D1: For queue metadata
• Analytics: For queue metrics

Error Handling

The command includes:

• Automatic retries with exponential backoff
• Dead letter queue for failed messages
• Error logging and alerting
• Message deduplication

Performance Considerations

• Batch processing for efficiency
• Concurrent message handling
• Memory-efficient processing
• Optimized for edge runtime

Related Commands

• add-worker-cron - Schedule queue processors
• add-r2-storage - For file processing queues
• setup-analytics - Monitor queue performance