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# Utility Functions
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Utility functions for HTTP status code validation and common operations with node-fetch.
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## Capabilities
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### isRedirect Function
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Utility function to check if an HTTP status code represents a redirect response.
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```javascript { .api }
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/**
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 * Check if HTTP status code is a redirect
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 * @param code - HTTP status code to check
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 * @returns True if code is 301, 302, 303, 307, or 308
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 */
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function isRedirect(code: number): boolean;
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```
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**Usage Examples:**
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```javascript
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import { isRedirect } from 'node-fetch';
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// Check redirect status codes
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console.log(isRedirect(301)); // true - Moved Permanently
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console.log(isRedirect(302)); // true - Found
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console.log(isRedirect(303)); // true - See Other
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console.log(isRedirect(307)); // true - Temporary Redirect
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console.log(isRedirect(308)); // true - Permanent Redirect
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// Non-redirect status codes
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console.log(isRedirect(200)); // false - OK
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console.log(isRedirect(404)); // false - Not Found
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console.log(isRedirect(500)); // false - Internal Server Error
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// Use in response handling
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const response = await fetch('https://example.com/some-endpoint');
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if (isRedirect(response.status)) {
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  console.log('Response is a redirect');
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  const location = response.headers.get('location');
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  console.log('Redirect location:', location);
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} else {
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  console.log('Response is not a redirect');
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}
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// Custom redirect handling logic
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async function fetchWithRedirectInfo(url) {
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  const response = await fetch(url, { redirect: 'manual' });
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  return {
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    response,
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    isRedirect: isRedirect(response.status),
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    location: response.headers.get('location')
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  };
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}
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const result = await fetchWithRedirectInfo('https://github.com/nodejs/node');
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if (result.isRedirect) {
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  console.log(`Redirect detected: ${response.url} -> ${result.location}`);
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}
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```
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### Supported Redirect Codes
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The `isRedirect` function checks for the following HTTP status codes:
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```javascript { .api }
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type RedirectStatusCode = 301 | 302 | 303 | 307 | 308;
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```
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- **301 Moved Permanently**: The resource has been moved permanently to a new location
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- **302 Found**: The resource temporarily resides at a different location
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- **303 See Other**: The response can be found at a different location using GET
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- **307 Temporary Redirect**: The resource temporarily resides at a different location, method must not change
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- **308 Permanent Redirect**: The resource has been moved permanently, method must not change
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**Integration with fetch redirect options:**
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```javascript
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// Manual redirect handling with isRedirect
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const response = await fetch('https://example.com', { redirect: 'manual' });
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if (isRedirect(response.status)) {
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  const location = response.headers.get('location');
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  // Custom logic for different redirect types
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  switch (response.status) {
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    case 301:
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    case 308:
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      console.log('Permanent redirect to:', location);
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      break;
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    case 302:
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    case 307:
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      console.log('Temporary redirect to:', location);
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      break;
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    case 303:
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      console.log('See other at:', location);
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      break;
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  }
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}
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```