Api Route Creator

Step 3: Add TypeScript Types

// src/types/api.ts
export interface CreateUserRequest {
  name: string;
  email: string;
}

export interface CreateUserResponse {
  success: boolean;
  data: User;
}

export interface ApiError {
  error: string;
  message?: string;
}

Step 4: Add Validation

import { z } from 'zod';

const CreateUserSchema = z.object({
  name: z.string().min(1).max(100),
  email: z.string().email()
});

app.post('/api/users', async (req, res) => {
  try {
    const parsed = CreateUserSchema.parse(req.body);
    // ... rest of handler
  } catch (error: any) {
    if (error instanceof z.ZodError) {
      return res.status(400).json({ 
        error: 'Validation failed',
        details: error.errors 
      });
    }
    // ... handle other errors
  }
});

Step 5: Add Tests

// tests/api/users.test.ts
import { describe, it, expect } from 'vitest';

describe('POST /api/users', () => {
  it('creates a new user', async () => {
    const response = await fetch('/api/users', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ name: 'Test', email: '[email protected]' })
    });
    
    expect(response.status).toBe(201);
    const data = await response.json();
    expect(data.success).toBe(true);
  });
  
  it('validates required fields', async () => {
    const response = await fetch('/api/users', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({})
    });
    
    expect(response.status).toBe(400);
  });
});

API Patterns

Error Handling

try {
  // Operation
} catch (error: any) {
  console.error('Operation failed:', error);
  res.status(500).json({ 
    error: error.message || 'An unexpected error occurred' 
  });
}

Response Format

// Success
{
  success: true,
  data: { ... },
  message?: string
}

// Error
{
  success: false,
  error: string,
  details?: any
}

Pagination

interface PaginatedResponse<T> {
  data: T[];
  total: number;
  page: number;
  limit: number;
  hasMore: boolean;
}

Best Practices

• Always use try-catch for async operations
• Validate all input with Zod
• Return consistent response formats
• Use appropriate HTTP status codes
• Log errors but don't expose internals
• Add rate limiting for public endpoints
• Use path traversal protection for file operations
• Sanitize user input

Example

User: "Add an endpoint to create a new project"

You:

1. Add POST /api/projects route to server.ts
2. Add validation schema with Zod
3. Create project in workspace directory
4. Return project data with 201 status
5. Add error handling
6. Create test file
7. Add TypeScript types