API Gateway Patterns

# API Gateway Patterns

API gateways are the front door to your microservices. Here's how to use them effectively.

## Core Responsibilities

**Routing**

Direct requests to appropriate backend services.

**Authentication & Authorization**

Centralized security. JWT validation, OAuth flows.

**Rate Limiting**

Protect backends from overload. Per-user, per-API limits.

**Request/Response Transformation**

Adapt legacy backends to modern clients.

## Advanced Features

**Caching**

Cache responses at the edge. Reduce backend load.

**Aggregation**

Combine multiple backend calls into one response.

**Protocol Translation**

REST to gRPC, HTTP to WebSocket.

## Patterns

**Backend for Frontend (BFF)**

Separate gateways per client type. Mobile, web, IoT.

**Service Mesh Integration**

Gateway handles north-south, mesh handles east-west traffic.

## Popular Solutions

- Kong

- AWS API Gateway

- Azure API Management

- Traefik

- Nginx

Gateways simplify client complexity.