Amazon SQS - Producing & Consuming Messages

Producing Messages

• Producers use AWS SDKs or API calls like SendMessage or SendMessageBatch.

• Messages remain stored in SQS until explicitly deleted by consumers.

• Common pattern: Include attributes such as Order ID, Customer ID, or metadata.

Consuming Messages

• Consumers (EC2, Lambda, on-premise apps, etc.) poll the queue using ReceiveMessage.

• Can receive up to 10 messages per API call.

• After processing, messages must be deleted explicitly via DeleteMessage.

• Visibility Timeout:
• Period during which a received message is hidden from other consumers.
• Prevents duplicate processing while a consumer is still working on it.
• Default: 30 seconds, configurable up to 12 hours.

Scaling and Monitoring

• CloudWatch metrics like ApproximateNumberOfMessagesVisible help monitor queue depth.

• Auto Scaling Groups (ASGs) can be configured to scale based on queue length.

• Consumers can be horizontally scaled to increase processing throughput.