Key Features of API Gateways
While simple routing is the core function, modern API Gateways are powerful platforms that offer a wide array of features. Here are the most critical ones.1. Routing and Load Balancing#
Path-based Routing: /users -> User Service, /products -> Product Service.
Load Balancing: If the User Service has 3 instances, the Gateway distributes traffic among them (Round Robin, Least Connections) to ensure high availability.
2. Authentication and Authorization (Auth Offloading)#
Instead of every microservice validating JWTs, the Gateway does it globally.The Gateway checks the Authorization header.
If valid, it passes the request to the backend (often adding a header like X-User-ID: 123 so the backend knows who it is).
If invalid, it returns 401 immediately, protecting the backend from bad traffic.
3. Rate Limiting and Throttling#
Protects your services from being overwhelmed (DDoS or accidental spikes).Rate Limiting: "User A can make 100 requests per minute."
Throttling: "Create a queue if requests exceed 1000/sec, processing them slowly instead of dropping them."
Monetization: You can sell API tiers (Bronze: 100 calls/day, Gold: Unlimited) enforcing these limits at the Gateway.
Example: The Client speaks classical REST (HTTP/JSON), but the legacy backend speaks SOAP (XML), or the modern backend speaks gRPC. The Gateway converts the payload on the fly.
Data Masking: Removing sensitive fields (e.g., stripping credit_card_id) from the response before sending it to the client.
Header Modification: Adding Trace-ID headers for observability.
6. Caching#
Reduce load on the backend by caching frequent read responses.If 10,000 users ask for "Get Product Categories" (which rarely changes), the Gateway serves the cached version, hitting the database only once every 10 minutes.
7. Monitoring and Analytics#
Since all traffic flows through the Gateway, it is the perfect place to gather metrics.
Key Takeaways#
Gateways handle Road Traffic (Routing, Load Balancing) and Security (Auth, Rate Limiting).
They can also perform Transformation (REST to gRPC) and Caching to optimize performance.
Modified atΒ 2025-12-29 04:29:59
