AWS Nov 21, 2019

Improving GraphQL API performance and consistency with AWS AppSync Caching and DynamoDB Transactions support

Article Summary

AWS just shipped two features that solve opposite problems: making GraphQL APIs blazing fast and keeping DynamoDB writes bulletproof. Here's how they change the game for mobile backends.

AWS AppSync now supports server-side caching and DynamoDB transactions for GraphQL APIs. These features address two critical mobile app challenges: reducing latency for frequently accessed data and ensuring data consistency across complex operations.

Key Takeaways

Critical Insight

AppSync now offers managed caching to cut API latency and DynamoDB transactions to guarantee all-or-nothing writes across multiple tables.

The article reveals a clever trick for caching event names while keeping comments live, plus how to invalidate stale cache without waiting for TTL expiration.

About This Article

Problem

E-commerce applications deal with different data update patterns. Inventory volumes change frequently, customer profiles update occasionally, and transaction IDs never change. When you access data sources directly, it adds latency and hurts performance.

Solution

AWS AppSync lets developers cache specific GraphQL fields or query operations with custom TTL values through per-resolver caching. Other fields can still hit live data sources directly.

Impact

The AppSync monitoring dashboard shows how well caching works by tracking hits, misses, evictions, and bytes used. Developers can measure performance improvements without having to maintain infrastructure.