fIt is a way for clients to talk to AWS resources. They access the REST API, which then proxies to AWS resources.
Lambda + API Gateway: No infrastructure
- Support for the WebSocket protocol
- Handle different environments, API versions, and security
- Transform and validate requests and responses
Integration
Lambda Function
- Invoke functions
- Easy way to expose REST API backed by AWS Lambda
HTTP
- Expose HTTP endpoints in the backend
- Example: internal HTTP API on premise, ALB…
- Why? Add rate limiting, caching, user auth, API keys…
AWS Service
- Expose any AWS API through the API Gateway
- Example: start an AWS Step Function workflow, post a message to SQS
Endpoint Types
Edge Optimized
- Default, for global clients
- Requests are routed through CloudFront Edge locations (improved latency)
- API Gateway still lives in only one region
Regional:
- For clients with the same region
- Can manually combine with CloudFront (more control)
Private:
- Can only be accessed from VPC using interface VPC endpoint (ENI)
- Use a resource policy to define access