What is an API Gateway?

Imagine a hotel concierge - they coordinate everything for you. That's what an API Gateway does!

The Problem

Without API Gateway

Mobile app needs to call 12 different microservices - Slow, many network calls, hard to manage!

The Solution

Python - Simple Gateway
from flask import Flask, jsonify
import requests

app = Flask(__name__)

@app.route('/api/user/')
def get_user(user_id):
    response = requests.get(f"http://user-service:8080/users/{user_id}")
    return jsonify(response.json())

Production API Gateway Patterns

Build robust API Gateways with authentication, rate limiting, and caching.

Backend for Frontend (BFF) Pattern

Different clients need different data - mobile app vs web vs IoT device.

Rate Limiting

Python - Rate Limiter
import redis

def rate_limit(max_requests=100, window=60):
    redis_client = redis.Redis()
    # Implementation here
    pass

Advanced Gateway Patterns

Enterprise-grade API Gateway with GraphQL federation and service mesh integration.

Netflix API Gateway

  • Dynamic Routing: Routes to different backends
  • Security: Authentication, SSL termination
  • Resilience: Circuit breakers, retries, timeouts

Scale: Handles billions of requests daily