REST API with DynamoDB Integration
Understand how to create a REST API integrated with DynamoDB through AWS API Gateway to implement atomic counters. Explore using UpdateItem and PutItem APIs, request and response mappings with Velocity templates, and how to maintain atomicity in distributed systems. Gain practical knowledge to deploy and test APIs managing event counters securely and efficiently.
We'll cover the following...
Atomic counter
Every architect dreams of an independent distributed system where all transactions process independently of the others. Such ideals remain ideals. Despite all the care, we do end up with scenarios where we need some shared resources like counters. An atomic counter is required in many applications. We need a way to count events and assign a unique number to events while ensuring we do not have a race condition.
Note: Atomicity on a distributed, eventually consistent database may seem counterintuitive, but we can make it work with a trick. We can configure the DynamoDB updates to return the updated value immediately. So, the update may take time to propagate within the database. However, the API invoking the update gets the updated value without conflict. AWS documentation ...