# Etsy API v3 Client

[![npm version](https://badge.fury.io/js/%40profplum700%2Fetsy-v3-api-client.svg)](https://badge.fury.io/js/%40profplum700%2Fetsy-v3-api-client)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
[![TypeScript](https://img.shields.io/badge/%3C%2F%3E-TypeScript-%230074c1.svg)](http://www.typescriptlang.org/)

A modern, universal TypeScript/JavaScript client for the Etsy Open API v3 with full OAuth 2.0 PKCE authentication support. Works seamlessly in both browser and Node.js environments.

This repository is heavily based on the official Etsy OpenAPI specification (`https://www.etsy.com/openapi/generated/oas/3.0.0.json`), as referenced in Etsy's API documentation (`https://developers.etsy.com/documentation/reference`).

## 🚀 Features

- **Universal Compatibility**: Works in browsers, Node.js, and Web Workers
- **OAuth 2.0 PKCE Authentication**: Full support for secure authentication flow
- **TypeScript First**: Complete type definitions with IntelliSense support
- **Rate Limiting**: Built-in request throttling to respect API limits
- **Token Management**: Automatic token refresh with configurable storage
- **Caching**: Optional response caching to improve performance
- **Error Handling**: Comprehensive error types for different failure scenarios
- **Zero Dependencies**: No external runtime dependencies

## 📦 Installation

```bash
npm install @profplum700/etsy-v3-api-client
```

```bash
yarn add @profplum700/etsy-v3-api-client
```

```bash
pnpm add @profplum700/etsy-v3-api-client
```

## 🔧 Quick Start

### Basic Setup

```typescript
import { EtsyClient, AuthHelper } from '@profplum700/etsy-v3-api-client';

// Create authentication helper
const authHelper = new AuthHelper({
  keystring: 'your-api-key',
  redirectUri: 'https://your-app.com/callback',
  scopes: ['shops_r', 'listings_r']
});

// Get authorization URL
const authUrl = await authHelper.getAuthUrl();
console.log('Visit this URL to authorize:', authUrl);

// After user authorization, exchange code for tokens
const state = await authHelper.getState();
await authHelper.setAuthorizationCode('authorization-code-from-callback', state);
const tokens = await authHelper.getAccessToken();

// Create API client
const client = new EtsyClient({
  keystring: 'your-api-key',
  sharedSecret: 'your-shared-secret', // REQUIRED for v3 API compliance
  accessToken: tokens.access_token,
  refreshToken: tokens.refresh_token,
  expiresAt: tokens.expires_at
});

// Make API calls
const user = await client.getUser();
console.log('User:', user);
```

### Browser Usage

```html
<script type="module">
import { EtsyClient, AuthHelper } from 'https://unpkg.com/@profplum700/etsy-v3-api-client/dist/browser.esm.js';

// Your code here...
</script>
```

Or using UMD:

```html
<script src="https://unpkg.com/@profplum700/etsy-v3-api-client/dist/browser.umd.js"></script>
<script>
const { EtsyClient, AuthHelper } = EtsyApiClient;
// Your code here...
</script>
```

### Node.js Usage

```javascript
// CommonJS
const { EtsyClient, AuthHelper } = require('@profplum700/etsy-v3-api-client');

// ES Modules
import { EtsyClient, AuthHelper } from '@profplum700/etsy-v3-api-client';
```

## 🔐 Authentication

### OAuth 2.0 Flow

1. **Create AuthHelper** with your app credentials
2. **Generate authorization URL** for user to visit
3. **Handle callback** with authorization code
4. **Exchange code for tokens**
5. **Use tokens** with EtsyClient

```typescript
import { AuthHelper, ETSY_SCOPES } from '@profplum700/etsy-v3-api-client';

const authHelper = new AuthHelper({
  keystring: 'your-api-key',
  redirectUri: 'https://your-app.com/callback',
  scopes: [
    ETSY_SCOPES.SHOPS_READ,
    ETSY_SCOPES.LISTINGS_READ,
    ETSY_SCOPES.PROFILE_READ
  ]
});

// Step 1: Get authorization URL
const authUrl = await authHelper.getAuthUrl();
// Redirect user to authUrl

// Step 2: Handle callback (in your callback endpoint)
const { code, state } = getCallbackParams(); // Your implementation
const expectedState = await authHelper.getState();

if (state === expectedState) {
  await authHelper.setAuthorizationCode(code, state);
  const tokens = await authHelper.getAccessToken();
  // Store tokens securely
}
```

### Available Scopes

```typescript
import { ETSY_SCOPES, COMMON_SCOPE_COMBINATIONS } from '@profplum700/etsy-v3-api-client';

// Individual scopes
const scopes = [
  ETSY_SCOPES.SHOPS_READ,
  ETSY_SCOPES.LISTINGS_WRITE,
  ETSY_SCOPES.TRANSACTIONS_READ
];

// Pre-defined combinations
const readOnlyScopes = COMMON_SCOPE_COMBINATIONS.SHOP_READ_ONLY;
const managementScopes = COMMON_SCOPE_COMBINATIONS.SHOP_MANAGEMENT;
```

## 🏪 Client Usage

### Creating a Client

```typescript
import { EtsyClient } from '@profplum700/etsy-v3-api-client';

const client = new EtsyClient({
  keystring: 'your-api-key',
  sharedSecret: 'your-shared-secret', // Get this from Your Apps page on Etsy
  accessToken: 'user-access-token',
  refreshToken: 'user-refresh-token',
  expiresAt: new Date('2024-12-31T23:59:59Z'),

  // Optional configuration
  rateLimiting: {
    enabled: true,
    maxRequestsPerSecond: 5,
    maxRequestsPerDay: 5000
  },
  caching: {
    enabled: true,
    ttl: 300 // 5 minutes
  }
});
```

### Making API Calls

```typescript
// Get current user
const user = await client.getUser();

// Get user's shops
const shops = await client.getUserShops();

// Get shop listings
const listings = await client.getListingsByShop('shop-id');

// Get specific listing
const listing = await client.getListing('listing-id');

// Search listings
const searchResults = await client.findAllListingsActive({
  keywords: 'vintage',
  taxonomy_id: 123,
  limit: 25
});
```

### Error Handling

```typescript
import { EtsyApiError, EtsyAuthError, EtsyRateLimitError } from '@profplum700/etsy-v3-api-client';

try {
  const user = await client.getUser();
} catch (error) {
  if (error instanceof EtsyAuthError) {
    // Handle authentication errors
    console.error('Auth error:', error.message, error.code);
  } else if (error instanceof EtsyRateLimitError) {
    // Handle rate limiting
    console.error('Rate limited. Retry after:', error.retryAfter);
  } else if (error instanceof EtsyApiError) {
    // Handle API errors
    console.error('API error:', error.statusCode, error.message);
  } else {
    // Handle other errors
    console.error('Unexpected error:', error);
  }
}
```

## 💾 Token Storage

### Built-in Storage Options

The client provides several storage mechanisms:

```typescript
import { 
  createDefaultTokenStorage,
  LocalStorageTokenStorage,
  SessionStorageTokenStorage,
  FileTokenStorage,
  MemoryTokenStorage
} from '@profplum700/etsy-v3-api-client';

// Automatic storage selection based on environment
const storage = createDefaultTokenStorage();

// Browser localStorage
const localStorage = new LocalStorageTokenStorage('etsy-tokens');

// Browser sessionStorage  
const sessionStorage = new SessionStorageTokenStorage('etsy-tokens');

// Node.js file storage
const fileStorage = new FileTokenStorage('./tokens.json');

// In-memory storage (not persistent)
const memoryStorage = new MemoryTokenStorage();

// Use with client
const client = new EtsyClient(config, storage);
```

### Custom Storage

```typescript
import { TokenStorage } from '@profplum700/etsy-v3-api-client';

class CustomTokenStorage implements TokenStorage {
  async save(tokens: EtsyTokens): Promise<void> {
    // Your save implementation
  }

  async load(): Promise<EtsyTokens | null> {
    // Your load implementation
  }

  async clear(): Promise<void> {
    // Your clear implementation
  }
}
```

## 🚦 Rate Limiting

The client includes built-in rate limiting to respect Etsy's API limits:

```typescript
const client = new EtsyClient({
  // ... other config
  rateLimiting: {
    enabled: true,
    maxRequestsPerSecond: 5,     // Requests per second (Etsy's limit)
    maxRequestsPerDay: 5000,     // Requests per day (Etsy's limit)
    minRequestInterval: 200      // Minimum ms between requests (1000 / 5 QPS)
  }
});

// Check remaining requests
const remaining = client.getRemainingRequests();
console.log(`${remaining} requests remaining today`);
```

## 🔄 Caching

Optional response caching to improve performance:

```typescript
const client = new EtsyClient({
  // ... other config
  caching: {
    enabled: true,
    ttl: 300 // Cache for 5 minutes
  }
});

// Clear cache when needed
await client.clearCache();
```

## 🌐 Environment Support

### Browser
- Modern browsers with ES2020+ support
- Web Workers
- Service Workers

### Node.js
- Node.js 20+
- Full CommonJS and ES Module support

### Package Exports
The package provides optimized builds for different environments:

```json
{
  "imports": {
    "@profplum700/etsy-v3-api-client": "./dist/index.esm.js",
    "@profplum700/etsy-v3-api-client/browser": "./dist/browser.esm.js",
    "@profplum700/etsy-v3-api-client/node": "./dist/node.esm.js"
  }
}
```

## 📚 API Reference

### EtsyClient Methods

#### User Methods
- `getUser()` - Get current user info
- `getUserShops(userId?)` - Get user's shops

#### Shop Methods
- `getShop(shopId)` - Get shop details
- `getShopByOwnerUserId(userId)` - Get shop by owner user ID

#### Personalization Methods (New)
- `getListingPersonalizations(listingId)` - Get personalization questions for a listing
- `updateListingPersonalization(shopId, listingId, params)` - Create or update personalization questions
- `deleteListingPersonalization(shopId, listingId)` - Delete personalization

#### Listing Methods
- `getListing(listingId)` - Get listing details
- `getListingsByShop(shopId, options?)` - Get shop's listings
- `findAllListingsActive(options?)` - Search active listings

#### Listing Management Endpoint Support
| Category | Endpoint | Supported |
| --- | --- | --- |
| BuyerTaxonomy | getBuyerTaxonomyNodes | Yes |
| BuyerTaxonomy | getPropertiesByBuyerTaxonomyId | No |
| SellerTaxonomy | getSellerTaxonomyNodes | Yes |
| SellerTaxonomy | getPropertiesByTaxonomyId | Yes |
| ShopListing | createDraftListing | Yes |
| ShopListing | getListingsByShop | Yes |
| ShopListing | deleteListing | Yes |
| ShopListing | getListing | Yes |
| ShopListing | findAllListingsActive | Yes |
| ShopListing | findAllActiveListingsByShop | No |
| ShopListing | getListingsByListingIds | No |
| ShopListing | getFeaturedListingsByShop | No |
| ShopListing | deleteListingProperty | No |
| ShopListing | updateListingProperty | Yes |
| ShopListing | getListingProperty | No |
| ShopListing | getListingProperties | Yes |
| ShopListing | updateListing | Yes |
| ShopListing | getListingsByShopReceipt | No |
| ShopListing | getListingsByShopReturnPolicy | No |
| ShopListing | getListingsByShopSectionId | No |
| ShopListing | getListingPersonalization | Yes |
| ShopListing | updateListingPersonalization | Yes |
| ShopListing | deleteListingPersonalization | Yes |
| ShopListing File | deleteListingFile | No |
| ShopListing File | getListingFile | No |
| ShopListing File | getAllListingFiles | No |
| ShopListing File | uploadListingFile | No |
| ShopListing Image | deleteListingImage | Yes |
| ShopListing Image | getListingImage | Yes |
| ShopListing Image | getListingImages | Yes |
| ShopListing Image | uploadListingImage | Yes |
| ShopListing Inventory | getListingInventory | Yes |
| ShopListing Inventory | updateListingInventory | Yes |
| ShopListing Offering | getListingOffering | No |
| ShopListing Product | getListingProduct | No |
| ShopListing Translation | createListingTranslation | No |
| ShopListing Translation | getListingTranslation | No |
| ShopListing Translation | updateListingTranslation | No |
| ShopListing VariationImage | getListingVariationImages | No |
| ShopListing VariationImage | updateVariationImages | No |
| ShopListing Video | deleteListingVideo | No |
| ShopListing Video | getListingVideo | No |
| ShopListing Video | getListingVideos | No |
| ShopListing Video | uploadListingVideo | No |
| Other | ping | No |
| Other | tokenScopes | No |
| Ledger Entry | getShopPaymentAccountLedgerEntry | Yes |
| Ledger Entry | getShopPaymentAccountLedgerEntries | Yes |
| Payment | getShopPaymentByReceiptId | No |
| Payment | getPaymentAccountLedgerEntry | No |
| Payment | getPayments | No |
| Shop Receipt | getShopReceipt | Yes |
| Shop Receipt | updateShopReceipt | Yes |
| Shop Receipt | getShopReceipts | Yes |
| Shop Receipt | searchAllShopReceipts | No |
| Shop Receipt Transactions | getShopReceiptTransaction | Yes |
| Shop Receipt Transactions | getShopReceiptTransactionsByListing | No |
| Shop Receipt Transactions | getShopReceiptTransactionsByReceipt | Yes |
| Shop Receipt Transactions | getShopReceiptTransactionsByShop | No |
| Review | getReviewsByListing | Yes |
| Review | getReviewsByShop | Yes |
| Shop HolidayPreferences | getShopHolidayPreferences | No |
| Shop HolidayPreferences | updateShopHolidayPreferences | No |
| Shop ProcessingProfiles | createShopShippingProfileUpgrade | No |
| Shop ProcessingProfiles | getShopShippingProfileUpgrades | Yes |
| Shop ProcessingProfiles | deleteShopShippingProfileUpgrade | No |
| Shop ProcessingProfiles | getShopShippingProfileUpgrade | No |
| Shop ProcessingProfiles | updateShopShippingProfileUpgrade | No |
| Shop ShippingProfile | getShippingCarriers | No |
| Shop ShippingProfile | createShopShippingProfile | Yes |
| Shop ShippingProfile | getShopShippingProfiles | Yes |
| Shop ShippingProfile | deleteShopShippingProfile | Yes |
| Shop ShippingProfile | getShopShippingProfile | Yes |
| Shop ShippingProfile | updateShopShippingProfile | Yes |
| Shop ShippingProfile | createShopShippingProfileDestination | Yes |
| Shop ShippingProfile | getShopShippingProfileDestinationsByShippingProfile | Yes |
| Shop ShippingProfile | deleteShopShippingProfileDestination | Yes |
| Shop ShippingProfile | updateShopShippingProfileDestination | Yes |
| Shop ShippingProfile | createShopShippingProfileUpgrade | No |
| Shop ShippingProfile | getShopShippingProfileUpgrades | Yes |
| Shop ShippingProfile | deleteShopShippingProfileUpgrade | No |
| Shop ShippingProfile | updateShopShippingProfileUpgrade | No |
| Shop | getShop | Yes |
| Shop | updateShop | Yes |
| Shop | getShopByOwnerUserId | Yes |
| Shop | findShops | No |
| Shop ProductionPartner | getShopProductionPartners | Yes |
| Shop Section | createShopSection | Yes |
| Shop Section | getShopSections | Yes |
| Shop Section | deleteShopSection | Yes |
| Shop Section | getShopSection | Yes |
| Shop Section | updateShopSection | Yes |
| Shop Return Policy | consolidateShopReturnPolicies | No |
| Shop Return Policy | createShopReturnPolicy | No |
| Shop Return Policy | getShopReturnPolicies | No |
| Shop Return Policy | deleteShopReturnPolicy | No |
| Shop Return Policy | getShopReturnPolicy | No |
| Shop Return Policy | updateShopReturnPolicy | No |
| User | getUser | Yes |
| User | getMe | No |
| UserAddress | deleteUserAddress | No |
| UserAddress | getUserAddress | No |
| UserAddress | getUserAddresses | No |

#### Review Methods
- `getReviewsByListing(listingId, options?)` - Get reviews for a listing        
- `getReviewsByShop(shopId, options?)` - Get reviews for a shop

#### Search Methods
- `findAllListingsActive(params)` - Search listings with filters

### AuthHelper Methods
- `getAuthUrl()` - Generate authorization URL
- `setAuthorizationCode(code, state)` - Set auth code from callback
- `getAccessToken()` - Exchange code for tokens
- `getState()` - Get current state parameter
- `getCodeVerifier()` - Get PKCE code verifier

### TokenManager Methods
- `getAccessToken()` - Get current access token (refreshes if needed)
- `refreshToken()` - Manually refresh tokens
- `getCurrentTokens()` - Get current token set
- `isTokenExpired()` - Check if token is expired
- `clearTokens()` - Clear stored tokens

## 🛠️ Configuration Options

```typescript
interface EtsyClientConfig {
  keystring: string;                    // Required: Your API key
  sharedSecret: string;                 // Required: Your shared secret (from Your Apps page)
  accessToken?: string;                 // User's access token
  refreshToken?: string;                // User's refresh token
  expiresAt?: Date;                     // Token expiration date
  refreshSave?: (token, refresh, expires) => void; // Token save callback

  rateLimiting?: {
    enabled?: boolean;                  // Enable rate limiting
    maxRequestsPerSecond?: number;      // Requests per second limit
    maxRequestsPerDay?: number;         // Daily request limit  
    minRequestInterval?: number;        // Minimum interval between requests (ms)
  };
  
  caching?: {
    enabled?: boolean;                  // Enable response caching
    ttl?: number;                       // Cache TTL in seconds
  };
}
```

## 📝 Examples

### Complete Authentication Flow

```typescript
import { AuthHelper, EtsyClient, createDefaultTokenStorage } from '@profplum700/etsy-v3-api-client';

async function authenticateAndFetchData() {
  // Step 1: Initialize authentication
  const authHelper = new AuthHelper({
    keystring: process.env.ETSY_API_KEY!,
    redirectUri: 'http://localhost:3000/callback',
    scopes: ['shops_r', 'listings_r', 'profile_r']
  });

  // Step 2: Get authorization URL
  const authUrl = await authHelper.getAuthUrl();
  console.log('Visit:', authUrl);

  // Step 3: Handle callback (pseudo-code)
  const { code, state } = await waitForCallback();
  const expectedState = await authHelper.getState();
  
  if (state !== expectedState) {
    throw new Error('State mismatch');
  }

  // Step 4: Exchange for tokens
  await authHelper.setAuthorizationCode(code, state);
  const tokens = await authHelper.getAccessToken();

  // Step 5: Create client with storage
  const storage = createDefaultTokenStorage();
  const client = new EtsyClient({
    keystring: process.env.ETSY_API_KEY!,
    ...tokens
  }, storage);

  // Step 6: Use the API
  const user = await client.getUser();
  const shops = await client.getUserShops();
  
  if (shops.length > 0) {
    const listings = await client.getListingsByShop(shops[0].shop_id.toString());
    console.log(`Found ${listings.length} listings`);
  }
}
```

### Simple Browser Example

Here's a complete working example for browser environments:

```html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Etsy API Client - Browser Example</title>
</head>
<body>
    <div id="app">
        <h1>Etsy API Browser Example</h1>
        <button id="loginBtn">Login with Etsy</button>
        <div id="userInfo" style="display: none;">
            <h2>User Information</h2>
            <div id="userData"></div>
            <button id="getShopsBtn">Get My Shops</button>
            <div id="shopsData"></div>
        </div>
    </div>

    <script type="module">
        import { AuthHelper, EtsyClient, ETSY_SCOPES } from 'https://unpkg.com/@profplum700/etsy-v3-api-client@1.0.0/dist/browser.esm.js';

        // Replace with your actual API key
        const API_KEY = 'your-api-key-here';
        const REDIRECT_URI = window.location.origin + window.location.pathname;

        let authHelper;
        let client;

        // Initialize auth helper
        function initAuth() {
            authHelper = new AuthHelper({
                keystring: API_KEY,
                redirectUri: REDIRECT_URI,
                scopes: [
                    ETSY_SCOPES.SHOPS_READ,
                    ETSY_SCOPES.LISTINGS_READ,
                    ETSY_SCOPES.PROFILE_READ
                ]
            });
        }

        // Handle login button click
        document.getElementById('loginBtn').addEventListener('click', async () => {
            const authUrl = await authHelper.getAuthUrl();
            window.location.href = authUrl;
        });

        // Handle OAuth callback
        async function handleCallback() {
            const urlParams = new URLSearchParams(window.location.search);
            const code = urlParams.get('code');
            const state = urlParams.get('state');

            if (code && state) {
                try {
                    const expectedState = await authHelper.getState();
                    
                    if (state === expectedState) {
                        await authHelper.setAuthorizationCode(code, state);
                        const tokens = await authHelper.getAccessToken();
                        
                        // Create client
                        client = new EtsyClient({
                            keystring: API_KEY,
                            accessToken: tokens.access_token,
                            refreshToken: tokens.refresh_token,
                            expiresAt: tokens.expires_at,
                            rateLimiting: { enabled: true },
                            caching: { enabled: true, ttl: 300 }
                        });

                        // Store tokens in localStorage for persistence
                        localStorage.setItem('etsy_tokens', JSON.stringify(tokens));
                        
                        // Clear URL parameters
                        window.history.replaceState({}, document.title, window.location.pathname);
                        
                        // Show user info
                        await showUserInfo();
                    } else {
                        console.error('State mismatch');
                    }
                } catch (error) {
                    console.error('Authentication failed:', error);
                    alert('Authentication failed. Please try again.');
                }
            }
        }

        // Show user information
        async function showUserInfo() {
            try {
                const user = await client.getUser();
                
                document.getElementById('loginBtn').style.display = 'none';
                document.getElementById('userInfo').style.display = 'block';
                document.getElementById('userData').innerHTML = `
                    <p><strong>User ID:</strong> ${user.user_id}</p>
                    <p><strong>Login Name:</strong> ${user.login_name || 'N/A'}</p>
                    <p><strong>Primary Email:</strong> ${user.primary_email || 'N/A'}</p>
                `;
            } catch (error) {
                console.error('Failed to get user info:', error);
                alert('Failed to get user information.');
            }
        }

        // Get user shops
        document.getElementById('getShopsBtn').addEventListener('click', async () => {
            try {
                const shops = await client.getUserShops();
                
                if (shops.length > 0) {
                    const shopsHtml = shops.map(shop => `
                        <div style="border: 1px solid #ccc; padding: 10px; margin: 10px 0;">
                            <h3>${shop.shop_name}</h3>
                            <p><strong>Shop ID:</strong> ${shop.shop_id}</p>
                            <p><strong>Title:</strong> ${shop.title || 'N/A'}</p>
                            <p><strong>URL:</strong> <a href="${shop.url}" target="_blank">${shop.url}</a></p>
                        </div>
                    `).join('');
                    
                    document.getElementById('shopsData').innerHTML = `
                        <h3>Your Shops (${shops.length})</h3>
                        ${shopsHtml}
                    `;
                } else {
                    document.getElementById('shopsData').innerHTML = '<p>No shops found.</p>';
                }
            } catch (error) {
                console.error('Failed to get shops:', error);
                alert('Failed to get shop information.');
            }
        });

        // Check for existing tokens on page load
        async function checkExistingAuth() {
            const storedTokens = localStorage.getItem('etsy_tokens');
            
            if (storedTokens) {
                try {
                    const tokens = JSON.parse(storedTokens);
                    
                    // Check if tokens are still valid
                    if (new Date(tokens.expires_at) > new Date()) {
                        client = new EtsyClient({
                            keystring: API_KEY,
                            ...tokens,
                            rateLimiting: { enabled: true },
                            caching: { enabled: true, ttl: 300 }
                        });
                        
                        await showUserInfo();
                    } else {
                        // Tokens expired, clear them
                        localStorage.removeItem('etsy_tokens');
                    }
                } catch (error) {
                    console.error('Failed to restore session:', error);
                    localStorage.removeItem('etsy_tokens');
                }
            }
        }

        // Initialize the application
        initAuth();
        await handleCallback();
        await checkExistingAuth();
    </script>
</body>
</html>
```

This example demonstrates:
- Complete OAuth 2.0 flow in the browser
- Token persistence using localStorage
- Error handling for authentication failures
- Making API calls to get user and shop information
- Automatic session restoration on page reload

### React Hook Example

```typescript
import { useState, useEffect } from 'react';
import { EtsyClient, createDefaultTokenStorage } from '@profplum700/etsy-v3-api-client';

function useEtsyClient(tokens) {
  const [client, setClient] = useState(null);

  useEffect(() => {
    if (tokens) {
      const storage = createDefaultTokenStorage({ preferSession: true });
      const etsyClient = new EtsyClient({
        keystring: process.env.REACT_APP_ETSY_API_KEY,
        ...tokens,
        rateLimiting: { enabled: true },
        caching: { enabled: true, ttl: 300 }
      }, storage);
      
      setClient(etsyClient);
    }
  }, [tokens]);

  return client;
}
```

## 📚 Documentation

Comprehensive documentation and examples are available in the `docs/` directory:

### Guides

- [Getting Started](docs/guides/getting-started.md) - Quick start guide and basic usage
- [Authentication](docs/guides/authentication.md) - Complete OAuth 2.0 authentication guide
- [Listing Management](docs/guides/listing-management.md) - Creating and managing listings
- [Order Fulfillment](docs/guides/order-fulfillment.md) - Processing orders and shipments
- [Shipping Profiles](docs/guides/shipping-profiles.md) - Managing shipping profiles
- [Webhooks](docs/guides/webhooks.md) - Real-time event notifications

### Troubleshooting

- [Common Issues](docs/troubleshooting/common-issues.md) - Solutions to common problems

### Example Applications

Complete, working example applications demonstrating various use cases:

- [Simple Shop Manager](examples/simple-shop-manager/) - Basic CLI shop management
- [Bulk Listing Updater](examples/bulk-listing-updater/) - Batch operations on listings
- [Order Fulfillment App](examples/order-fulfillment-app/) - Automated order processing
- [Inventory Sync](examples/inventory-sync/) - Real-time inventory synchronization
- [Analytics Dashboard](examples/analytics-dashboard/) - Shop metrics and reporting
- [Production Template](examples/production-template/) - Production-ready deployment template

## 🤝 Contributing

Contributions are welcome! Please read our [Contributing Guidelines](CONTRIBUTING.md) for details.

1. Fork the repository
2. Create your feature branch: `git checkout -b feature/amazing-feature`
3. Commit your changes: `git commit -m 'Add amazing feature'`
4. Push to the branch: `git push origin feature/amazing-feature`
5. Open a Pull Request

## 📄 License

This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.

## 🔗 Links

- [Etsy Open API Documentation](https://developers.etsy.com/documentation)
- [OAuth 2.0 PKCE Specification](https://tools.ietf.org/html/rfc7636)
- [Package on npm](https://www.npmjs.com/package/@profplum700/etsy-v3-api-client)
- [GitHub Repository](https://github.com/profplum700/etsy-v3-api-client)

## ❓ Support

If you have questions or need help:

1. Check the [API Documentation](https://developers.etsy.com/documentation)
2. Search [GitHub Issues](https://github.com/profplum700/etsy-v3-api-client/issues)
3. Create a new issue if your question isn't answered

## 🏷️ Changelog

See [CHANGELOG.md](CHANGELOG.md) for version history and release notes.