Cant do POST in PHP

Question

I found function:

function loginGeoserver($username, $password) {

$geoserverURL = "http://localhost:8080/geoserver/j_acegi_security_check";

$post = http_build_query(array(
        "username" => $username,
        "password" => $password,
));

$context = stream_context_create(array("http"=>array(
    "method" => "POST",
    "header" => "Content-Type: application/x-www-form-urlencoded\r\n" .
            "Content-Length: ". strlen($post) . "\r\n",
    "content" => $post,
)));

$page = file_get_contents($geoserverURL, false, $context);


for($i = 0; $i < sizeof($http_response_header); $i++){

    $headerLine = $http_response_header[$i];

    $pos = strpos($headerLine, 'Set-Cookie');

    if ($pos === 0) {
            $str = explode("=",$headerLine);
            $value = explode(";",$str[1]);
            $cookieValue = $value[0];
            break;
    }

}

$cookieName = "JSESSIONID";
$cookieDomain = "localhost:8080";
$cookiePath = "/geoserver";
$cookieExpiration = 0;

setcookie($cookieName,$cookieValue,$cookieExpiration,$cookiePath);

return $cookieValue;
} 
loginGeoserver('admin', 'geoserver');

But when try it i get an error:

Notice: Undefined variable: cookieValue in D:\xampp\htdocs\rest\index.php on line 87

So how i understand that mean that this line $page = file_get_contents($geoserverURL, false, $context); not work.
Im new with php. Give me any ideas why its not work.
And more i dont see that something posted on url http://localhost:8080/geoserver/j_acegi_security_check.

Answer 1

If $pos is different than 0 the variable $cookieValue is not defined:

You only define it in the case is 0:

if ($pos === 0) {
        $str = explode("=",$headerLine);
        $value = explode(";",$str[1]);
        $cookieValue = $value[0];
        break;
}

You should define it at the start of the function with some default value for the case $pos is not 0.