SQS (Simple Queue Service) et SNS (Simple Notification Service) sont des services de messagerie AWS qui permettent une communication découplée et asynchrone entre les composants d'une application. SQS est une file de messages (traitement un-à-un) ; SNS est un pub/sub (diffusion un-à-plusieurs).
SQS — files de messages (découplage, traitement asynchrone)
SQS is a managed message QUEUE: producers send messages, consumers process them:
→ producer → [QUEUE] → consumer(s) process messages (at their own pace)
→ DECOUPLES components (producer doesn't wait for/depend on the consumer)
→ BUFFERS load (queue absorbs spikes; consumers process steadily)
→ RELIABLE (messages persist until processed; retries; dead-letter queues for failures)
→ SCALABLE (add more consumers to process faster)
→ Use for: async task processing, decoupling services, smoothing load spikes
