Build a Secure API Gateway for Microservices

In microservice architectures, services often expose multiple APIs to internal or external consumers. Without a secure API gateway, these services are vulnerable to unauthorized access, brute-force attacks, and data leaks. A well-configured gateway acts as the first line of defense, enforcing security policies and managing traffic efficiently.

The gateway acts as a reverse proxy and central point of control for incoming requests. It verifies identity using JWT or OAuth tokens, applies rate limits, inspects requests for malicious patterns, and routes them securely to the target microservice with audit logging.

Every incoming request first passes through the API Gateway. It authenticates the user via tokens, checks for throttling violations, inspects payloads, and then forwards the request to the correct service. Logging and metrics are collected for audit and monitoring.

• API client sends request with authentication token to the gateway.
• Gateway validates token and checks if the user has access to the requested resource.
• It applies rate limiting, request body validation, and content filtering.
• Gateway forwards the request to the target microservice securely over HTTPS.
• All interactions are logged and can be monitored in a dashboard.

• Kong Gateway Documentation
• Express Gateway Overview
• JWT.io – JSON Web Tokens
• OAuth 2.0 Protocol Guide
• Nginx as API Gateway