API Gateway

2 min read

Related: Lambda
Service made to create and manage APIs. Endpoint/entry point for applications.
Sits between applications and backend services (integration)
Highly available scaleable. Is a public service, so can connect to on-premise too.
Throttle control - how many requests can be sent per API key

HTTP APIs, REST APIs and WebSocket APIs

Authentication

NOTE

Can be setup without authentication

Amazon Cognito:
Lambda Authorizer:
IAM Passing Credentials with headders..

Endpoint types

  1. Edge optimized - route to nearest CloudFront POP
  2. Regional - covering specific region
  3. Private - accessible only within VPC via interface endpoint

Stages

When you deploying API, you do it with stages, like dev.. prod..
Provides isolation and testing. Also, there are Canary deployments which can be upgrade into the new base stage

Errors

  • 4XX - Client-side errors. Invalid requests on client side
  • 5XX - Server Error. Valid request, backend issue

Also.

  • 400 - Generic client-side error
  • 403 - Access denied - Authorizer denies or Web Application Firewall (WAF) Filtered
  • 429 - API Gateway can throttle - this means you’ve exceeded that amount (Too many requests)
  • 502 - Bad Gateway Exception - bad output from backend (like bad output from lambda)
  • 503 - Service Unavailable backend endpoint offline? Major service issues.
  • 504 - Integration failure/Timeout 29s limit for lambda to provide a request to API Gateway.
    Common Errors - Amazon API Gateway

Caching

IMPORTANT

Cache is setup per stage

Default TTL is 300s - can be min 0s max 3600s
Cache can be encrypted
Cache size 500MB to 237GB.

Demo

Graph View

Backlinks