API Design

Overview

API (Application Programming Interface) design is the process of defining the endpoints, request/response formats, and communication protocols for your services. Well-designed APIs are intuitive, consistent, and versioned to ensure long-term maintainability.

Key Concepts

1. REST (Representational State Transfer)

  • Verbs: GET, POST, PUT, DELETE, PATCH.
  • Principles: Stateless, cacheable, uniform interface.
  • Strengths: Ubiquitous, easy to understand, works over HTTP.

2. gRPC

  • Mechanism: Remote Procedure Call using Protocol Buffers (protobuf).
  • Strengths: High performance (binary format), strongly typed, supports streaming.
  • Weaknesses: Harder for browser clients to use directly, less human-readable.

3. GraphQL

  • Mechanism: Single endpoint where the client specifies exactly what data it needs.
  • Strengths: Eliminates over-fetching and under-fetching, great for complex data graphs.

Trade-offs & Considerations

  • Versioning: How do you handle changes without breaking clients? (e.g., /v1/, header-based).
  • Rate Limiting: Protecting your API from abuse and ensuring fair usage.
  • Documentation: Essential for developer adoption (e.g., Swagger/OpenAPI).
  • Security: Authentication (OAuth2, JWT) and Authorization (RBAC).

Further Reading