How can a solutions architect design a system to durably store the number of calls without requiring changes to the application?
Call the service through an internet gateway.
Decouple the application from the service with an Amazon Simple Queue Service (Amazon SQS) queue.
Publish a custom Amazon CloudWatch metric that counts calls to the service.
Call the service through a VPC peering connection.
Explanations:
Calling the service through an internet gateway does not provide a mechanism for tracking or storing the number of calls made. It is primarily a network routing method and does not address the requirement for tracking calls.
Decoupling the application using Amazon SQS would help with handling requests asynchronously, but it does not inherently track the number of calls to the service. It also introduces unnecessary complexity and does not meet the need for durable call tracking.
Publishing a custom CloudWatch metric is the most efficient solution for tracking service calls. It allows you to count the number of calls to the service and provides a durable, easily accessible log that can be used for billing validation.
A VPC peering connection is used to connect VPCs and is not relevant to tracking the number of calls to an external service. It does not provide any logging or tracking functionality for counting calls.
If I’m correct, the answer is:
Publish a custom Amazon CloudWatch metric that counts calls to the service.