Getting content from URL through a PHP proxy

TSUrlRelay.php

<?php


function val($array, $key)
	{
	if (!$array) return null;
	if (!isset($array[$key])) return null;
	return $array[$key];
	}


// For proxy purpose, $excludeHeaders = array('Date', 'Server', 'X-Powered-By', 'Transfer-Encoding')
function TSParseCurlResponse($res, $excludeHeaders = null)
	{
	try
		{
		list($headers, $body) = explode("\r\n\r\n", $res, 2);
		
		$headerDict = array();
		$headerLines = explode("\r\n", $headers);
		$statusText = null;
		for ($i=0; $i<count($headerLines); $i++)
			{
			$header = $headerLines[$i];
			if ($i == 0)
				{
				$statusText = $header;
				}
			else
				{
				if (!$header) continue;
				$split = explode(':', $header, 2);
				if (count($split) != 2) continue;
				
				$headerName = trim($split[0]);
				$headerValue = trim($split[1]);
				
				// check if header should be ignored
				if ($excludeHeaders && in_array($headerName, $excludeHeaders)) continue;

				// add to result
				$headerDict[$headerName] = $headerValue;
				}
			}
	
	
		if ($statusText)
			{
			$splits = explode(' ', $statusText, 3);
			if (count($splits) == 3)
				{
				$statusCode = $splits[1];
				$statusText = $splits[2];
				}
			}
		}
	catch (Exception $ex)
		{
		$json['error'] = $ex->getMessage();
		}
	
	$ret = array();
	$ret['responseText'] = $body;
	$ret['statusText'] = $statusText;
	$ret['statusCode'] = $statusCode;
	$ret['headers'] = $headerDict;
	return $ret;
	}


/**
 * TSCurl executes a curl command
 *
 * @param $url					URL
 * @param $opt.method			HTTP method
 * @param $opt.cookie			Cookie header
 * @param $opt.contentType		Content type header
 * @param $opt.referer			Referer header
 * @param $opt.params			Keyed array to build the query string
 * @param $opt.payload			Raw content for post method
 * @param $opt.parseResponse	if true, the returned response is passed to TSParseCurlResponse
 * @param $opt.excludeHeaders	if $opt.parseResponse is true, excludeHeaders will be passed to TSParseCurlResponse
 *
 * @returns HTTP resonse (with raw response header lines)
 */
function TSCurl($url, $opt = null)
	{
	$ch = curl_init($url);
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
	curl_setopt($ch, CURLOPT_HEADER, TRUE);
	curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE);

	// set referer
	$referer = val($opt, 'referer');
	if ($referer) curl_setopt($ch, CURLOPT_REFERER, $referer);

	// set cookie
	$cookie = val($opt, 'cookie');
	curl_setopt ($ch, CURLOPT_COOKIE, $cookie);

	// get payload or build payload from params
	$payload = val($opt, 'payload');
	if (!$payload)
		{
		$params = val($opt, 'params');
		if ($params)
			{
			$payload = http_build_query($params);
			}
		}

	// get method
	$method = val($opt, 'method');
	if ($method == 'post')
		{
		$contentType = val($opt, 'contentType');
		if (!$contentType) $contentType = 'application/x-www-form-urlencoded';
		curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
		curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: $contentType; charset=utf-8"));
		if ($payload) curl_setopt($ch, CURLOPT_POSTFIELDS, $payload);
		}
	else
		{
		if ($payload)
			{
			$connector = strpos($url, '?') === FALSE? '?': '&';
			$url = $url . $connector . $payload;
			curl_setopt($ch, CURLOPT_URL, $url);
			}
		}


	$ret = curl_exec($ch);
	if ($ret === false)
		{
		$err = curl_error($ch);
		curl_close($ch);
		throw new Exception($err);
		}
	else
		{
		curl_close($ch);
		
		$parse = !!val($opt, 'parse'); 
		if ($parse)
			{
			$excludeHeaders = val($opt, 'excludeHeaders');
			$ret = TSParseCurlResponse($ret, $excludeHeaders);
			}
		
		return $ret;
		}
	}


function TSOutputCurlResponse($res)
	{
	if (gettype($res) == 'string')
		{
		$res = TSParseCurlResponse($res, array('Date', 'Server', 'X-Powered-By', 'Transfer-Encoding'));
		}
	$headerDict = $res['headers'];
	$body = $res['responseText'];
	$statusText = $ret['statusText'];
	$statusCode = $ret['statusCode'];

	header("$statusCode $statusText");

	if ($headerDict) foreach ($headerDict as $name => $value)
		{
		header("$name: $value");
		}
	echo $body;
	}


function TSUrlRelay($url, $referer = null)
	{
	if (!$referer)
		{
		$pos = strrpos($url, '/');
		if ($pos > 0) $referer = substr($url, 0, $pos + 1);
		}
	$res = TSCurl($url, array('referer' => $referer, 'params' => $_REQUEST));
	TSOutputCurlResponse($res);
	}