X-Ray

AWS X-Ray
-         https://docs.aws.amazon.com/xray/latest/devguide/aws-xray.html
-         a service that collects data about requests that your application serves, and provides tools you can use to view, filter, and gain insights into that data to identify issues and opportunities for optimization.
-         Traces requests as they travel through application components/microservices; builds a component map. This helps with:
          §  Bulging a dependency tree
          §  Detecting latency issues across regions / AZs
          §  Identify services not operating as expected
          §  Identify errors / bugs

-         You can use AWS X-Ray to trace and analyze user requests as they travel through your Amazon API Gateway APIs to the underlying services. API Gateway supports AWS X-Ray tracing for all API Gateway endpoint types: regional, edge-optimized, and private. You can use AWS X-Ray with Amazon API Gateway in all regions where X-Ray is available

-         X-Ray gives you an end-to-end view of an entire request, so you can analyze latencies in your APIs and their backend services. You can use an X-Ray service map to view the latency of an entire request and that of the downstream services that are integrated with X-Ray. And you can configure sampling rules to tell X-Ray which requests to record, at what sampling rates, according to criteria that you specify. If you call an API Gateway API from a service that's already being traced, API Gateway passes the trace through, even if X-Ray tracing is not enabled on the API

-         You can enable X-Ray for an API stage by using the API Gateway management console, or by using the API Gateway API or CLI.

Components:
-         Trace – collection of data point sharing a TraceID
-         Segment – all data points in a single component
-         Sampling – data NOT FOR EVERY request is collected from a component – X-RAY can NOT be used as a compliance tool that requires data completeness
-         Annotation – system or user-defined data associated with a segment

-         Errors – annotations for a segment that responded with an error to an X-Ray call