Web API Design: REST, GraphQL, and Beyond

Web APIs power modern apps, from mobile clients to cloud services. REST and GraphQL are popular choices, but the best design fits who uses the API and what data they need. A good design helps teams move fast and keeps integrations reliable.

REST basics

REST treats data as resources exposed at clear URLs. Actions use standard HTTP methods: GET to read, POST to create, PUT or PATCH to update, and DELETE to remove. Status codes communicate results, while headers guide caching and versioning. For example, GET /books lists books, GET /books/42 retrieves one item, and POST /books creates a new book. Think about pagination for large lists, filtering for client needs, and a version in the path or header to avoid breaking changes.

GraphQL at a glance

GraphQL centers on a single endpoint with a typed schema. Clients ask for exactly the fields they need, which reduces over-fetching. A query might look like: query { book(id: 42) { title author { name } } }. Pros include precise data shape and fast front ends when data needs vary a lot. Cons include more complex caching, harder validation, and a steeper learning curve for teams new to schemas. GraphQL shines when front ends require many optional fields or rapid schema evolution.

Decision guide: REST, GraphQL, or something else

  • When REST fits well:

    • Clear, stable resources and straightforward CRUD.
    • Wide client support and predictable caching.
    • Simple versioning needs and limited changes.

  • When GraphQL fits well:

    • Front ends that request different fields across screens.
    • Frequent changes in data shape or new fields.
    • Multiple clients sharing the same backend.

  • When to consider other patterns:

    • Real-time updates or streaming data (WebSockets, server-sent events).
    • High-performance RPC needs between services (gRPC).
    • Complex, event-driven architectures with loose coupling.

Examples help: REST can serve a resource like books with GET /books and GET /books/42, while GraphQL can fetch specific fields in one call.

Beyond basics: practice and care

No matter the choice, focus on three pillars: clear documentation, strong security, and solid observability. Use OpenAPI or similar specs for REST APIs to help clients learn and test. For GraphQL, provide a clean schema, helpful error messages, and introspection. Plan caching, rate limiting, and versioning from the start. Regularly review API surface, remove deprecated paths thoughtfully, and keep dashboards for latency and error rates.

In short, REST and GraphQL each offer strengths. A pragmatic approach often blends both: stable REST for core resources and GraphQL for flexible client needs. Think about your users, your teams, and the data you share.

Key Takeaways

  • REST and GraphQL have different strengths; pick based on data shape, client needs, and ecosystem.
  • Documentation, versioning, and security should be built in from day one.
  • Consider future needs like real-time data or service-to-service communication when designing the API.