API Gateway vs Direct Service Exposure PDF

208 API Gateway vs Direct Service * * Exposure ** API Gateway and Direct Service Exposure are two approaches to exposing **...

208 API Gateway vs Direct Service * * Exposure ** API Gateway and Direct Service Exposure are two approaches to exposing ** ** ** * ** services and APIs in a microservices architecture or a distributed system. Each ** * approach has its own benefits and is suitable for different scenarios. API Gateway ** Definition: An API Gateway is a single entry point for all clients to access various ** *** ** services in a microservices architecture. It acts as a reverse proxy, routing requests * *** *** * from clients to the appropriate backend services. * ** Characteristics: ** ** Aggregation: The gateway aggregates requests and responses from various ** services. ** Cross-Cutting Concerns: Handles cross-cutting concerns like authentication, ** authorization, rate limiting, and logging. ** Simplifies Client Interaction: Clients interact with one endpoint, simplifying the ** client-side logic. ** Example: An e-commerce platform where the API Gateway routes user requests to ** *** *** *** ** appropriate services like product catalog, user accounts, or order processing. * *** *** *** *** *** *** A mobile app client makes a single request to the API Gateway to get a user’s * * * * * profile and order history, * and the gateway routes this request to the respective services. *** *** *** *** * * ** Pros: ** ** Centralized Management: Simplifies management of cross-cutting ** * * * * * functionalities. *  ❗ ** Reduced Complexity for Clients: Clients need to know only the endpoint of the ** * ** ** API Gateway, not the individual services. * *** ** ~~ ~~ * ** Enhanced Security: Provides an additional layer of security by offering ** * ** centralized authentication and SSL termination. ** ** ** * ** Cons: ** ** Single Point of Failure: Can become a bottleneck if not properly managed. ** ** Increased Latency: Adding an extra network hop can increase response ** * * *** times. *** * Direct Service Exposure (no API Gateway) * ~~ ~~ ** Definition: In direct service exposure, each microservice or service is directly ** * * *** exposed to clients. Clients interact with each service through its own endpoint. *** ** Characteristics: ** *** Direct Access: Clients access services directly using individual service endpoints. * ** *** Decentralized: Each service manages its own cross-cutting concerns. *** * * ** Example: In a cloud storage service, clients might directly interact with separate ** *** *** endpoints for file uploads, downloads, and metadata retrieval. The client application has to manage multiple endpoints * * and handle cross-service functionalities like authentication for each service * * * * * separately. * ** Pros: ** ** Eliminates Single Point of Failure: Avoids the bottleneck of a central gateway. ~~ ~~** ** Potentially Lower Latency: Can offer reduced latency as requests do not go * * ** * through an additional layer. ~~ ~~ *  ❗ ** Cons: ** ** Increased Client Complexity: Clients must handle interactions with multiple * * ** services. *** Redundant Implementations: Cross-cutting concerns may need to be * ** implemented in each service. Key Differences ** Point of Contact: ** ** API Gateway provides a single point of contact for accessing multiple ** *** *** * * services, * while direct service exposure requires clients to interact with multiple * *** *** * * * * endpoints. ** Cross-Cutting Concerns: ** ** API Gateway centralizes common functionalities like security and rate ** * * * * *** *** *** limiting, *** * whereas in direct service exposure, these concerns are handled by each * ** ** * service. * Conclusion The choice between using an API Gateway and direct service exposure depends on ** ** ** ** * the specific requirements of the architecture and the trade-offs in terms of ** ** ** ** ** complexity, latency, and single points of failure. ** ** ** ** ** * ** API Gateways are beneficial for unifying access to a distributed system and ** * * * simplifying client interactions, making them suitable for complex, large-scale * * microservices architectures. * ** Direct service exposure can be more efficient in terms of latency and is simpler ** * * * architecturally but places more burden on the client to manage interactions with * *** *** * * * multiple services. *