Bespoke CloudFront Edge Metrics
When I migrated the Speedrun API from API Gateway to CloudFront, I lost an important latency metric; End-to-End (E2E) API latency. Detailed CloudFront metrics provide this latency metric and a few others, but I was curious to see if I could get more granular. Could I get realtime origin latency by edge location, software version and whether there was a coldstart? Kind of. In this post, I'll show how I used CloudFront Functions and the Embedded Metrics Format (EMF) to obtain more insight into my end user latency.