Code example

http.php

<?php

abstract class HTTP extends Kohana_HTTP {

	/**
	 * The standard Kohana_HTTP::redirect raises Out of memory fatal error sometimes
	 *
	 * We don't need redirects in HMVC, so we can use the straight-forward approach instead of throwing exception
	 */
	public static function redirect($uri = '', int $code = 302) : void
	{
		if ( ! str_contains($uri, '://'))
		{
			// Make the URI into a URL
			$uri = URL::site($uri, TRUE, ! empty(Kohana::$index_file));
		}

		header('HTTP/1.1 '.$code.' '.Response::$messages[$code]);
		header('Location: '.$uri);
		exit();
	}


	/**
	 * Checks the browser cache to see the response needs to be returned,
	 * execution will halt and a 304 Not Modified will be sent if the
	 * browser cache is up-to-date.
	 *
	 * @throws Request_Exception
	 */
	public static function check_cache(Request $request, Response $response, string $etag = NULL) : Response
	{
		// Generate an etag if necessary
		if ($etag === NULL)
		{
			$etag = $response->generate_etag();
		}

		// Set the ETag header
		$response->headers('ETag', $etag);

		// Add the Cache-Control header if it is not already set
		// This allows etags to be used with max-age, etc
		if ($response->headers('cache-control'))
		{
			$response->headers('cache-control', $response->headers('cache-control').', must-revalidate');
		}
		else
		{
			$response->headers('cache-control', 'must-revalidate');
		}

		// Check if we have a matching etag
		if (
			$request->headers('if-none-match') 
      			AND (
				(string) $request->headers('if-none-match') === $etag 
        			OR preg_replace('/^W\//', '', $request->headers('if-none-match')) === $etag 
      			)
    		)
		{
			// No need to send data again
			throw HTTP_Exception::factory(304)->headers('ETag', $etag);
		}

		return $response;
	}
}