PHP: checking if YT url is valid and if video exists - php

Question

The function purpose is to validate the URLs of a YouTube video and check if the video exists. This is a snippet of my actual code. I manipulate the string to my desired format and then i proceed to check if it is valid and exists. If it passes the test, then i echo the results. The problem is that I am not calling the function correctly.
I am getting this echo even though the video does exist:
The video does not exist or invalid url
Edited: and added isValidURL function
*Code for checking if video exist or is invalid:*
if($_POST)
{
// After applying url manipulation and getting the url in a proper format result = $formatted_url
function isValidURL($formatted_url) {
$formatted_url = trim($formatted_url);
$isValid = true;
if (strpos($formatted_url, 'http://') === false && strpos($formatted_url, 'https://') === false) {
$formatted_url = 'http://'.$formatted_url;
}
//first check with php's FILTER_VALIDATE_URL
if (filter_var($formatted_url, FILTER_VALIDATE_URL, FILTER_FLAG_HOST_REQUIRED) === false) {
$isValid = false;
} else {
//not all invalid URLs are caught by FILTER_VALIDATE_URL
//use our own mechanism
$host = parse_url($formatted_url, PHP_URL_HOST);
$dotcount = substr_count($host, '.');
//the host should contain at least one dot
if ($dotcount > 0) {
//if the host contains one dot
if ($dotcount == 1) {
//and it start with www.
if (strpos($host, 'www.') === 0) {
//there is no top level domain, so it is invalid
$isValid = false;
}
} else {
//the host contains multiple dots
if (strpos($host, '..') !== false) {
//dots can't be next to each other, so it is invalid
$isValid = false;
}
}
} else {
//no dots, so it is invalid
$isValid = false;
}
}
//return false if host is invalid
//otherwise return true
return $isValid;
}
$isValid = getYoutubeVideoID($formatted_url);
function isYoutubeVideo($formatted_url) {
$isValid = false;
//validate the url, see: http://snipplr.com/view/50618/
if (isValidURL($formatted_url)) {
//code adapted from Moridin: http://snipplr.com/view/19232/
$idLength = 11;
$idOffset = 3;
$idStarts = strpos($formatted_url, "?v=");
if ($idStarts !== FALSE) {
//there is a videoID present, now validate it
$videoID = substr($formatted_url, $idStarts + $idOffset, $idLength);
$http = new HTTP("http://gdata.youtube.com");
$result = $http->doRequest("/feeds/api/videos/".$videoID, "GET");
//returns Array('headers' => Array(), 'body' => String);
$code = $result['headers']['http_code'];
//did the request return a http code of 2xx?
if (substr($code, 0, 1) == 2) {
$isValid = true;
}
}
}
return $isValid;
}
$isValid = isYoutubeVideo($formatted_url);
parse_str($parsed_url['query'], $parsed_query_string);
$v = $parsed_query_string['v'];
if ( $isValid == true ) {
//Iframe code
echo htmlentities ('<iframe src="http://www.youtube.com/embed/'.$v.'" frameborder="0" width="'.$wdth.'" height="'.$hth.'"></iframe>');
//Old way to embed code
echo htmlentities ('<embed src="http://www.youtube.com/v/'.$v.'" width="'.$wdth.'" height="'.$hth.'" type="application/x-shockwave-flash" wmode="transparent" embed="" /></embed>');
}
else {
echo ("The video does not exist or invalid url");
}
}
?>

Answer 1

You are missing the isValidURL() function. Try changing this line:
if (isValidURL($formatted_url)) {
to
if(preg_match('/http:\/\/www\.youtube\.com\/watch\?v=[^&]+/', $formatted_url, $result)) {
or
$test = parse_url($formatted_url);
if($test['host']=="www.youtube.com"){