Form Validation API

import { useState } from 'react';

const API_KEY = process.env.REACT_APP_TINYFN_KEY;

async function validateField(type, value) {
  const endpoints = {
    email: `/v1/validate/email?email=${encodeURIComponent(value)}`,
    url: `/v1/validate/url?url=${encodeURIComponent(value)}`,
    phone: `/v1/validate/phone?phone=${encodeURIComponent(value)}&country=US`
  };

  const response = await fetch(`https://api.tinyfn.io${endpoints[type]}`, {
    headers: { 'X-API-Key': API_KEY }
  });
  return response.json();
}

export function RegistrationForm() {
  const [email, setEmail] = useState('');
  const [errors, setErrors] = useState({});

  const handleEmailBlur = async () => {
    const result = await validateField('email', email);
    if (!result.is_valid) {
      setErrors(prev => ({ ...prev, email: 'Please enter a valid email' }));
    } else {
      setErrors(prev => ({ ...prev, email: null }));
    }
  };

  return (
    <form>
      <input
        type="email"
        value={email}
        onChange={(e) => setEmail(e.target.value)}
        onBlur={handleEmailBlur}
        placeholder="Email address"
      />
      {errors.email && <span className="error">{errors.email}</span>}
    </form>
  );
}

import requests
from functools import lru_cache

API_KEY = os.environ.get('TINYFN_KEY')
BASE_URL = 'https://api.tinyfn.io/v1'

@lru_cache(maxsize=1000)
def validate_email(email: str) -> tuple[bool, str | None]:
    """Validate email with caching."""
    response = requests.get(
        f'{BASE_URL}/validate/email',
        params={'email': email},
        headers={'X-API-Key': API_KEY}
    )
    data = response.json()

    if data['is_valid']:
        return True, None
    return False, 'Invalid email address'


def validate_registration(data: dict) -> dict[str, str]:
    """Validate all registration fields."""
    errors = {}

    # Email validation
    is_valid, error = validate_email(data.get('email', ''))
    if not is_valid:
        errors['email'] = error

    # Password strength
    response = requests.get(
        f'{BASE_URL}/validate/password-strength',
        params={'password': data.get('password', '')},
        headers={'X-API-Key': API_KEY}
    )
    strength = response.json()
    if strength['score'] < 3:
        errors['password'] = f"Password too weak. {strength['feedback']}"

    return errors


# Usage in Flask/FastAPI
@app.post('/api/register')
def register(data: RegisterRequest):
    errors = validate_registration(data.dict())
    if errors:
        raise HTTPException(400, detail=errors)
    # Continue with registration...