Intermediate LevelSoftware Engineering Principles
What is the API Gateway Pattern and how does it handle cross-cutting concerns?
❓ Interview Prompt: Explain API Gateway pattern (Kong, NGINX, AWS API Gateway), request routing, SSL termination, rate limiting, auth offloading, and BFF pattern.
An API Gateway serves as the single reverse-proxy entry point for all client requests entering a microservice architecture:
Cross-Cutting Responsibilities Offloaded:
1
Request Routing: Routes client requests to target microservices.
2
Authentication & Authorization: Offloads JWT verification at the edge.
3
Rate Limiting & Throttling: Protects downstream microservices from DoS.
4
SSL/TLS Termination: Decrypts HTTPS traffic at the perimeter.
Code Implementation Example
yaml
# Kong API Gateway Routing & Plugin Config
services:
- name: user-service
url: http://user-service.internal:3000
routes:
- paths: [/api/v1/users]
plugins:
- name: rate-limiting
config: { minute: 100 }💡Configuring routing and rate-limiting plugins in Kong API Gateway.
🎯 Interview Key Takeaway
Deploy an API Gateway to centralize authentication, rate limiting, and request routing at the perimeter.
#API Gateway#Kong#Architecture#Intermediate
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