Phase 4: API Design & Implementation
Build robust backend APIs
Deliverables
1. API Specification
OpenAPI/Swagger format:
yamlopenapi: 3.0.0 info: title: User API version: 1.0.0 paths: /api/users: get: summary: List users responses: '200': description: User list content: application/json: schema: type: array items: $ref: '#/components/schemas/User' post: summary: Create user requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateUser'
2. Endpoint Implementation
typescript// app/api/users/route.ts import { NextRequest, NextResponse } from 'next/server'; export async function GET(request: NextRequest) { const users = await db.user.findMany(); return NextResponse.json(users); } export async function POST(request: NextRequest) { const body = await request.json(); const user = await db.user.create({ data: body }); return NextResponse.json(user, { status: 201 }); }
3. Error Handling
typescript// Standard error response { "error": { "code": "VALIDATION_ERROR", "message": "Invalid email format", "details": [ { "field": "email", "message": "Must be a valid email" } ] } }
API Patterns
- RESTful resource naming
- Consistent response format
- Proper HTTP status codes
- Input validation
- Rate limiting
Output
Save to: docs/02-design/api-spec.yaml
Next Phase
After completion: /phase-5-design-system or /phase-6-ui-integration
