PHP SendToHost function not working - php

Question

So I'm currently trying to implement the 'SendToHost' function that is widely used for 'GET' and 'POST' procedures. In my case, I want to use it for sending a 'postcode' to a shopping website's postcode input form for use with retrieving that postcode's specific catalogue. More specifically, the code should automatically generate the web page that has the results for the postcode. Below is my code coupled with the function and I'd like to know why it isn't working:
function SendToHost($host, $method, $path, $data, $useragent=0)
{
// Supply a default method of GET if the one passed was empty
if (empty($method))
$method = 'GET';
$method = strtoupper($method);
$fp = fsockopen($host,80);
if ($method == 'GET')
$path .= '?' . $data;
fputs($fp, "$method $path HTTP/1.1\n");
fputs($fp, "Host: $host\n");
fputs($fp, "Content-type: application/x-www-form-urlencoded\n");
fputs($fp, "Content-length: " . strlen($data) . "\n");
if ($useragent)
fputs($fp, "User-Agent: MSIE\n");
fputs($fp, "Connection: close\n\n");
if ($method == 'POST')
fputs($fp, $data);
while (!feof($fp))
$buf .= fgets($fp,128);
fclose($fp);
return $buf;
}
echo sendToHost('catalog.coles.com.au','get','/default.aspx','ctl00_Body_PostcodeTextBox=4122');

Answer 1

You are using the wrong new-line style in your headers. You need to use \r\n, not just \n.
A quote from the HTTP/1.1 docs:
HTTP/1.1 defines the sequence CR LF as the end-of-line marker for all protocol elements except the entity-body
Source: http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.2
If you are just sending simple POST/GET requests, I'd suggest using an HTTP library like cURL. There's no reason to manually open a socket and send headers unless you are doing something more complex.
function SendToHost($url, $data, $method='GET', $useragent=FALSE){
$ch = curl_init();
$options = array(
CURLOPT_RETURNTRANSFER => TRUE
);
if($method === 'POST'){
$options += array(
CURLOPT_URL => $url,
CURLOPT_POST => TRUE,
// Passing a string will set `application/x-www-form-urlencoded`
// Whereas an array will set `multipart/form-data`
CURLOPT_POSTFIELDS => http_build_query($data)
);
}
elseif($method === 'GET'){
$options[CURLOPT_URL] = $url . '?' . http_build_query($data);
}
if($useragent){
$options[CURLOPT_USERAGENT] = 'MSIE';
}
curl_setopt_array($ch, $options);
$buf = curl_exec($ch);
curl_close($ch);
return $buf;
}
You call this one slightly differently:
echo sendToHost('http://catalog.coles.com.au/default.aspx', array(
'ctl00_Body_PostcodeTextBox' => 4122
));
Heck, if you just want to send a GET request, you can even use file_get_contents:
echo file_get_contents('http://catalog.coles.com.au/default.aspx?ctl00_Body_PostcodeTextBox=4122');