26. How can I monitor my Amazon API Gateway APIs?
Amazon API Gateway logs API calls, latency, and error rates to Amazon CloudWatch in your AWS account. The metrics are also available through the Amazon API Gateway console in a REST API dashboard. API Gateway also meters utilization by third-party developers, the data is available in the API Gateway console and through the APIs.
27. Can I set up alarms on the Amazon API Gateway metrics?
Yes, Amazon API Gateway sends logging information and metrics to Amazon CloudWatch. You can utilize the Amazon CloudWatch console to set up custom alarms.
28. How can I protect my backend systems and applications from traffic spikes?
Amazon API Gateway provides throttling at multiple levels including global and by service call. Throttling limits can be set for standard rates and bursts. For example, API owners can set a rate limit of 1,000 requests per second for a specific method in their REST APIs, and also configure Amazon API Gateway to handle a burst of 2,000 requests per second for a few seconds. Amazon API Gateway tracks the number of requests per second. Any requests over the limit will receive a 429 HTTP response. The client SDKs (except Javascript) generated by Amazon API Gateway retry calls automatically when met with this response.
29. What happens if a large number of end users try to invoke my API simultaneously?
If caching is not enabled and throttling limits have not been applied, then all requests will pass through to your backend service until the account level throttling limits are reached. If throttling limits are in place, then Amazon API Gateway will shed the necessary amount of requests and send only the defined limit to your back-end service. If a cache is configured, then Amazon API Gateway will return a cached response for duplicate requests for a customizable time, but only if under configured throttling limits. This balance between the backend and client ensures optimal performance of the APIs for the applications that it supports.
