REST API Basics
REST (Representational State Transfer) uses HTTP methods (GET, POST, PUT, DELETE) to perform operations on resources identified by URLs. It's been the standard for web APIs for over a decade.
REST Example
GET /api/users/123
Response: Single user object
GET /api/users/123/posts
Response: All posts by user 123
GET /api/users/123/posts?limit=10
Response: First 10 posts
REST Characteristics
- ✓ Resource-based URLs
- ✓ HTTP verbs for actions
- ✓ Fixed response structures
- ✓ Stateless requests
- ✓ Cacheable responses
GraphQL Basics
GraphQL is a query language developed by Facebook. It allows clients to request exactly the data they need. A single GraphQL endpoint returns only requested fields.
GraphQL Example
{
user(id: 123) {
name
posts(limit: 10) {
title
createdAt
}
}
}
GraphQL Characteristics
- ✓ Single endpoint (usually /graphql)
- ✓ Query language for precise data selection
- ✓ Strongly typed schema
- ✓ Mutations for data changes
- ✓ Subscriptions for real-time updates
Head-to-Head Comparison
| Aspect | REST | GraphQL |
|---|---|---|
| Learning Curve | Easy to learn | Moderate to steep |
| Over/Under Fetching | Common problem | Eliminates both |
| Caching | Native HTTP caching | Requires tooling |
| Monitoring | Simple (per endpoint) | Complex (query-based) |
| Real-time Data | Requires polling | Subscriptions built-in |
| API Versioning | v1, v2, v3... | Schema evolution |
| Mobile Friendly | Good | Excellent (fetch only needed fields) |
Detailed Pros & Cons
REST Advantages
✓ Simple to understand and implement
✓ Great browser caching support
✓ Easy monitoring and debugging
✓ Wide ecosystem and tooling
✓ Native HTTP method semantics
GraphQL Advantages
✓ Eliminates over/under fetching
✓ Single endpoint for all data
✓ Strongly typed schema
✓ Built-in introspection
✓ Real-time with subscriptions
REST Disadvantages
✗ Over-fetching (extra data)
✗ Under-fetching (multiple requests)
✗ API versioning required
✗ Multiple endpoints to maintain
GraphQL Disadvantages
✗ Complex queries can be expensive
✗ Steep learning curve
✗ File uploads more complex
✗ Error handling less standard
When to Use Each
Use REST API When:
- ✓ Building simple CRUD APIs
- ✓ Team is unfamiliar with GraphQL
- ✓ Heavy browser caching is important
- ✓ File uploads are primary use case
- ✓ Easy monitoring/debugging needed
- ✓ Quick MVP development
Use GraphQL When:
- ✓ Multiple client types (web, mobile, IoT)
- ✓ Complex data relationships
- ✓ Real-time data needed (subscriptions)
- ✓ Bandwidth optimization critical (mobile)
- ✓ Complex query requirements
- ✓ Avoiding API versioning headaches
Implementation Guide
Building GraphQL API (Apollo)
npm install apollo-server-express
// Schema definition
const typeDefs = gql`
type Query {
user(id: ID!): User
}
type User {
id: ID!
name: String!
email: String!
}
`
Hybrid Approach
- ✓ Start with REST API
- ✓ Add GraphQL layer as needs grow
- ✓ Both serve different client types
- ✓ Gradually migrate to GraphQL
Best Practices
Security
Validate all inputs, implement authentication/authorization, rate limit queries.
Error Handling
Return meaningful errors with proper status codes. Log errors for debugging.
Documentation
Auto-generated docs (Swagger/GraphQL playground) keep docs in sync with code.
Versioning
REST: URL versioning. GraphQL: Schema evolution with deprecations.
Testing
Unit test resolvers, integration test endpoints, load test under realistic queries.
Monitoring
Track response times, error rates, slow queries, and resource usage.
Deploy Your APIs with Confidence
Build REST or GraphQL APIs and deploy with Spidey Host. Reliable infrastructure, automatic scaling, and monitoring included.
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