header.class.php

<?php
/*
* PHP Header Class
* By Timothy 'Tim' Oliver
*
* Streamlines and simplifies
* Header output calls made by PHP
*
* ============================================================================
* 
* Copyright (C) 2011 by Tim Oliver
* 
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* 
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
* 
*/

class Header
{
	//Hold output until called manually
	private $buffer = true;
	
	//Array of header strings
	private $header_strings = NULL;
	
	/*
	* Class Constructor
	*
	* $buffer - bool - Hold header output until called manually
	*/
	function __construct( $buffer = true )
	{
		$this->buffer 			= $buffer;
		$this->header_strings 	= array();
	}

	/*
	* 403 Error
	*
	* Return a 403 Error (Access denied) and terminates PHP if needed
	*/
	static function _403( $die = true )
	{
		//post 403 header
		header('HTTP/1.1 403 Forbidden');
		
		//kill the script
		if( $die )
			die();
	}

	/*
	* 404 Error
	*
	* Return a 404 Error (Page not Found) and terminates PHP if needed
	*/
	static function _404( $die = true )
	{
		//post 404 header
		header('HTTP/1.0 404 Not Found');
		
		//kill the script
		if( $die )
			die();
	}
	
	/*
	* redirect
	*
	* Perform a 302 redirect to another page.
	*/ 
	static function redirect( $url = '', $delay = 0, $die = true )
	{
		$delay_str = '';
		if( $delay > 0 )
			$delay_str = 'Refresh: '.$delay.'; ';
		
		if( $url )
			header( $delay_str.'Location: '.$url );
			
		if( $die )
			die();
	}
	
	/*
	* 200 Response
	*
	* Returns a header response of 200 (All good)
	*/
	function _200()
	{
		$this->do( 'HTTP/1.1 200 OK' );
	}
	
	/*
	* 206 Partial Response
	*
	* Returns a 206 response (partial file download)
	*/
	function _206()
	{
		$this->do( 'HTTP/1.1 206 Partial Content' );
	}

	/*
	* Powered By
	*
	* Modify the output header to specify a new output source
	*/
	function powered_by( $source = '' )
	{
		$this->do( 'X-Powered-By: '.$source );
	}
	
	/*
	* Length
	*
	* Sets the length of the response
	*/
	function content_length( $len = 0 )
	{
		$this->do( 'Content-Length: '.$len );
	}
	
	/*
	* Content Range
	*
	* Specifies the byte range of the data supplied (for partial downloads)
	*/
	function content_range( $start = 0, $end = 0, $next = 0 )
	{
		
	}
	
	/*
	* Download Name
	*
	* Sets the stream as a downloadable file and 
	* sets a name
	*/ 
	function download_name( $name = '' )
	{
		//defaulting these fixes an SSL glitch in IE
		$this->do( 'Expires: 0' );
		$this->do( 'Cache-Control: private' );
		$this->do( 'Pragma: cache' );
		
		$this->do( 'Content-Disposition: attachment; filename="'.$name.'"' );
	}
	
	/*
	* MIME type
	*
	* Set the MIME type of the output
	*/
	function mime( $mime_type = 'application/octet-stream' )
	{
		$this->do( 'Content-Type: '.$mime_type );
	}
	
	/*
	* Expires
	*
	* Sets the expiry date of the cache data here
	*/
	function expires( $time = 0 )
	{
		$this->do( 'Pragma: public' );
		$this->do( 'Cache-Control: maxage='.($time-time()) );
		$this->do( 'Expires: '.gmdate( 'D, d M Y H:i:s', $time).' GMT' );
	}
	
	/*
	* No cache
	*
	* Disables caching for the current request
	*/
	function no_cache()
	{
		$this->do( 'Cache-Control: no-cache, must-revalidate' );
		$this->do( 'Expires: Thu, 01 Jan 1970 00:00:00 GMT' );
	}
	
	/*
	* Add
	*
	* If buffering, add each string to an array, else
	* post it to the browser
	*/
	private function add( $string = '' )
	{
		if( $this->buffer )
			$this->header_strings[] = $string;
		else
			header( $string );
	}
	
	/*
	* Post
	*
	* Post the headers to the request
	*/
	function post()
	{
		foreach( $this->header_strings as $string )
			header( $string );
	}
}
?>