API Gateway — Complete Guide

API Gateway for Backend Services

Learn how API gateways centralize routing, authentication, rate limiting, and request transformation for backend services in distributed systems. robust

Introduction to API Gateway

Learn what an API Gateway is and how it serves as a single entry point for routing, authentication, rate limiting, and transforming API traffic in microservices.

Why API Gateway — Benefits and Use Cases

Learn why you need an API gateway: centralized authentication, rate limiting, request routing, protocol translation, and reduced client complexity in microservices.

Reverse Proxy Fundamentals — Complete Guide

Learn reverse proxy fundamentals: how it differs from forward proxy, request forwarding, load distribution, SSL termination, and its role in API gateway architecture.

Request Routing at the API Gateway

Learn request routing at the API gateway: path-based, header-based, method-based routing, service discovery integration, and dynamic route configuration patterns.

Load Balancing at the API Gateway

Learn load balancing at the API gateway: round-robin, least connections, IP hash, weighted distribution, health checks, and integration with service discovery.

Request Transformation at the API Gateway

Learn request transformation at the API gateway: header modification, body rewriting, query parameter manipulation, protocol conversion, and request enrichment patterns.

Response Transformation at the API Gateway

Learn response transformation at the API gateway: header modification, body rewriting, error standardization, response aggregation, and format conversion patterns.

Rate Limiting at the API Gateway

Learn rate limiting at the API gateway: token bucket, sliding window, distributed rate limiting with Redis, per-client limits, and gateway-level throttling patterns.

Authentication at the API Gateway

Learn authentication at the API gateway: JWT validation, OAuth2 integration, API key verification, single sign-on, and centralized authentication patterns.

Authorization at the API Gateway

Learn authorization at the API gateway: RBAC, ABAC, policy enforcement, scope validation, IP-based access control, and centralized authorization patterns.

API Key Management at the Gateway

Learn API key management at the gateway: key generation, hashing, rotation, revocation, tier-based rate limiting, and secure storage of API credentials.

IP Whitelisting at the API Gateway

Learn IP whitelisting at the API gateway: allow lists, CIDR range matching, geo-blocking, dynamic IP management, and IP-based access control patterns.

Circuit Breaker Pattern at the API Gateway

Learn the circuit breaker pattern at the API gateway: failure detection, open/closed/half-open states, fallback responses, and preventing cascading failures.

Gateway Caching Strategies — Complete Guide

Learn caching at the API gateway: response caching, cache keys, TTL strategies, cache invalidation, distributed caching with Redis, and CDN integration.

Request Aggregation at the API Gateway

Learn request aggregation at the API gateway: combining multiple backend responses, parallel requests, response composition, and reducing client round trips.

API Versioning at the Gateway

Learn API versioning at the gateway: routing versioned traffic, header-based version detection, backward compatibility, and migrating clients between versions.

WebSocket Gateway — Complete Guide

Learn WebSocket support at the API gateway: connection upgrade, long-lived connections, pub-sub routing, scaling WebSockets, and gateway-level WebSocket management.

Kong API Gateway — Complete Guide

Learn Kong API Gateway: service registration, route configuration, plugin system, rate limiting, authentication plugins, custom plugins, and Kong Manager.

NGINX as API Gateway — Complete Guide

Learn NGINX as API gateway: reverse proxy configuration, load balancing, SSL termination, rate limiting, caching, authentication, and routing rules.

Envoy Proxy — Complete Guide

Learn Envoy proxy: L7 routing, cluster management, circuit breakers, retry policies, observability, and dynamic configuration via xDS protocol.

AWS API Gateway — Complete Guide

Learn AWS API Gateway: REST and HTTP APIs, Lambda integration, stage management, usage plans, API keys, caching, throttling, and WebSocket support.

Gateway Security — Protecting Your API Gateway

Learn how to secure your API gateway against common attacks including injection, auth bypass, rate-limit abuse, and misconfigured CORS with practical defense strategies.

Azure API Management — Complete Guide

Learn Azure API Management: API import, policies, products, subscriptions, developer portal, version management, and integration with Azure Functions and App Service.

gRPC Gateway — Bridging HTTP and gRPC Services

Learn how to expose gRPC services through an API gateway using gRPC-Web, gRPC transcoding, and protocol translation for REST clients consuming gRPC backends.

Gateway Analytics — Monitoring Traffic Patterns and Metrics

Learn how to implement analytics at your API gateway: request counting, latency tracking, error rate monitoring, traffic pattern analysis, and business metric collection.

GraphQL Gateway — Complete Guide

Learn GraphQL gateway: schema federation, Apollo Federation, schema stitching, query planning, rate limiting for GraphQL, and combining REST with GraphQL.

Gateway Logging — Structured Logging for API Gateways

Learn how to implement structured logging at the API gateway level: correlation IDs, request/response capture, log levels, and integration with centralized logging systems.

Gateway Monitoring and Observability — Complete Guide

Learn gateway monitoring: metrics collection, request logging, distributed tracing, health checks, alerting, and integration with Prometheus and Grafana.

API Gateway Mini Project — Complete Guide

Build a complete API gateway simulation: routing, authentication, rate limiting, caching, response transformation, monitoring, and health checks end-to-end.

Rate Limiting Deep Dive — Algorithms, Strategies, and Distributed Limits

Learn advanced rate limiting algorithms for API gateways: token bucket, leaky bucket, sliding window, distributed counters with Redis, and adaptive rate limiting strategies.

Authentication at the Gateway — Deep Dive into Auth Strategies

Learn advanced authentication patterns at the API gateway: JWT validation, token introspection, multi-factor enforcement, API key rotation, and federated authentication.

Caching at the Gateway — Deep Dive into Request and Response Caching

Learn how to implement caching at the API gateway: response caching, cache invalidation, cache key strategies, stale-while-revalidate, and distributed cache backends.

JWT Authentication at the API Gateway — Validation and Claims Extraction

Learn how to validate JSON Web Tokens at the API gateway: signature verification, claim extraction, key rotation, JWKS endpoint integration, and secure header propagation.

OAuth2 at the Gateway — Authorization Code Flow and Token Management

Learn how to integrate OAuth2 with your API gateway: authorization code flow, token exchange, introspection, scope enforcement, and downstream header propagation.

API Key Authentication at the Gateway — Key Management and Security

Learn how to implement API key authentication at the API gateway: key generation, hashing, rotation, revocation, rate limiting per key, and secure key distribution patterns.

IP Filtering at the Gateway — Whitelists, Blacklists, and Geo-Blocking

Learn how to implement IP-based access control at the API gateway: whitelist and blacklist rules, CIDR range matching, geo-IP blocking, and dynamic IP reputation checks.

Retry Logic at the Gateway — Transient Failure Handling Strategies

Learn how to implement retry logic at the API gateway: exponential backoff, jitter, retry budgets, idempotency checks, and circuit breaker integration for resilient request handling.

Timeout Management at the Gateway — Request Deadlines and Cancellation

Learn how to implement timeout management at the API gateway: request deadlines, per-endpoint timeouts, timeout propagation, cancellation signals, and deadline-aware retries.

Header Manipulation at the Gateway — Request and Response Header Transformation

Learn how to manipulate HTTP headers at the API gateway: adding, removing, and transforming headers, forwarding client headers, and securing sensitive header information.

CORS at the API Gateway — Cross-Origin Resource Sharing Configuration

Learn how to configure CORS at the API gateway: origin validation, preflight handling, allowed methods and headers, credentials support, and per-route CORS policies.

Compression at the Gateway — Response Size Optimization Strategies

Learn how to implement response compression at the API gateway: gzip, brotli, and zstd compression, content negotiation, per-route compression policies, and performance tuning.

SSL Termination at the Gateway — Deep Dive into TLS Configuration

Learn how to implement SSL termination at the API gateway: certificate management, TLS versions, cipher suites, HSTS, mutual TLS, and performance optimization for TLS.

Gateway Clustering — High Availability and Horizontal Scaling

Learn how to cluster API gateways for high availability: shared state, leader election, health-based routing, zero-downtime deployments, and multi-region gateway topologies.

Load Balancing Algorithms for API Gateways — Round Robin to Consistent Hashing

Learn load balancing algorithms for API gateways: round robin, least connections, IP hash, consistent hashing, weighted distribution, and adaptive load-aware routing.

Canary Deployments with API Gateways — Gradual Traffic Shifting

Learn how to implement canary deployments through the API gateway: traffic splitting, gradual rollout, metrics-based promotion, rollback strategies, and A/B testing configurations.

Blue-Green Deployments with API Gateways — Zero-Downtime Releases

Learn how to implement blue-green deployments through the API gateway: environment switching, traffic draining, database compatibility, rollback strategies, and automated cutover.

Gateway Testing — Strategies for Testing API Gateway Configurations

Learn how to test API gateway configurations: unit testing plugins, integration testing routes, load testing performance, contract testing, and chaos engineering for gateways.

Gateway Monitoring with Prometheus and Grafana — Metrics Collection and Visualization

Learn how to monitor API gateways with Prometheus and Grafana: metric types, endpoint instrumentation, dashboard creation, alert rules, and SLO tracking for gateway performance.

Gateway Alerting — Automated Incident Detection and Response

Learn how to set up alerting for API gateways: Prometheus alert rules, Alertmanager configuration, notification channels, escalation policies, and incident response automation.

Gateway Performance Optimization — Throughput, Latency, and Resource Tuning

Learn how to optimize API gateway performance: connection pooling, request pipelining, caching strategies, worker thread tuning, TLS optimization, and scale-out architecture.

Gateway Scaling — Horizontal and Vertical Scaling Strategies

Learn how to scale API gateways: horizontal scaling with load balancers, vertical scaling limits, auto-scaling policies, database-backed state, and multi-region gateway deployment.

Gateway Plugins — Extending API Gateway Functionality

Learn how to use and configure API gateway plugins: authentication plugins, rate limiting, logging, transformation, monitoring, caching, and the plugin execution lifecycle.

Plugin Development for API Gateways — Building Custom Extensions

Learn how to develop custom plugins for API gateways: plugin structure, SDK usage, lifecycle hooks, configuration, testing, and distribution for Kong, Envoy, and custom gateways.

Gateway on Kubernetes — Deploying API Gateways in Container Orchestration

Learn how to deploy API gateways on Kubernetes: deployment manifests, service configuration, Ingress integration, ConfigMaps, horizontal pod autoscaling, and zero-downtime updates.

Gateway and Service Mesh — API Gateways with Istio and Linkerd

Learn how API gateways work with service mesh technology: sidecar proxies, mTLS, traffic policies, observability, and the division of responsibility between gateway and mesh.