API Gateway Pattern
Centralized entry point that handles cross-cutting concerns like authentication, rate limiting, and routing for microservices.
Medium ComplexityTechnologies & Tools
KongAWS API GatewayAzure API ManagementEnvoySpring Cloud Gateway
Architecture Flow
1
Client Request
Client sends request to API Gateway
HTTP/HTTPSRESTGraphQL
2
Authentication & Authorization
Validate JWT tokens and check permissions
JWTOAuth2RBAC
3
Request Routing
Route request to appropriate microservice
Load BalancerService DiscoveryRouting Rules
4
Response Aggregation
Aggregate responses from multiple services
Response CachingData Transformation
Use Cases
Multi-service applications
Mobile API backends
Third-party integrations
Legacy system modernization
Multi-tenant applications
Pros
Centralized security management
Simplified client integration
Request/response transformation
Rate limiting and throttling
API versioning support
Cons
Single point of failure
Performance overhead
Increased complexity
Vendor lock-in risk
Debugging challenges
When to Use
Multiple microservices
Need for centralized security
API management requirements
Client simplification needs
Cross-cutting concerns
Alternatives
Direct service communicationService meshBackend for frontendGraphQL federation
Performance Metrics
Latency
Low (milliseconds)
Throughput
High (thousands of requests/sec)
Scalability
Excellent
Reliability
High
Cost
Medium
Key Trade-offs
Single Point of Failure
Gateway failure affects all services
Centralized Control
Easier to manage security and policies
Performance Overhead
Additional latency for each request
Category Information
Category
API Gateway
Complexity Level
Medium