API Gateways

Responsibilities

• Caching
  • Responses can be cached by dedicated CDN servers that get hit
  • Responses can also be cached in memory with something like Valkey/Redis/Memcached
• Authentication and Authorization
  • The API gateway can easily handle auth by calling a SSO endpoint
• Rate Limiting
  • Rate limiting can easily be achieved by implementing a leaky bucket algorithm or by using other similar methods
• Failover
• Monitoring
  • Can provide metrics and logs to metric aggregators and log aggregators
• Load Balancing
  • The API gateway can serve as a Load Balancer, even tho that may not be the best way to handle things.
  • Load balancers can instead be put before or after the gateway
• Validation
  • Can be used to validate the requests or responses coming in/out
  • Can be useful to prevent errors from leaking to the outside
  • Can also lead to automatic Retries
• Circuit Breaker Pattern
• Service Discovery
• Web Application Firewall