Validating a link in php

Hi all,

I'm hoping y'all can help me with a bit of a php code problem I'm having.

What I'm trying to do is link to YouTube videos (more than one in a single
webpage). However, because I'm worried about the videos going away and the
links going bad, I'd like to use PHP to check if the link is good; if it's
good, display the video link, else display a static image that I have on my
servers.

Where I'm having troubles is in the checking of whether the url is good. I
think part of the problem is YouTube itself. I've tried file() and
fsockopen(), but neither seem to work.

Below is an example of the block of code I'm trying to write.

<?
error_reporting(E_ALL ^ E_NOTICE);
if (the "http://www.youtube.com/v/JqO8ZevPJNk" url is valid) <-- ???
{
echo " <object height=\"400\" width=\"475\">\n";
echo " <param name=\"movie\" value=\"http://www.youtube.com/v/JqO8ZevPJNk\">\n";
echo " <embed src=\"http://www.youtube.com/v/JqO8ZevPJNk\"\n";
echo " type=\"application/x-shockwave-flash\" height=\"400\" width=\"475\">\n";
echo " </object>\n";
}
else
{
echo " <a href=\"10538overturevideo.jpg\"><img SRC=\"10538overturevideo.jpg\" height=\"130\"></a>\n";
}
?>

Many thanks for any assistance you can provide.

Robert Porter

sleestak2@earthlink.net wrote:
> Hi all,
>
> I'm hoping y'all can help me with a bit of a php code problem I'm having.
>
> What I'm trying to do is link to YouTube videos (more than one in a single
> webpage). However, because I'm worried about the videos going away and the
> links going bad, I'd like to use PHP to check if the link is good; if it's
> good, display the video link, else display a static image that I have on my
> servers.
>
> Where I'm having troubles is in the checking of whether the url is good. I
> think part of the problem is YouTube itself. I've tried file() and
> fsockopen(), but neither seem to work.
>
> Below is an example of the block of code I'm trying to write.
>
> <?
> error_reporting(E_ALL ^ E_NOTICE);
> if (the "http://www.youtube.com/v/JqO8ZevPJNk" url is valid) <-- ???
> {
> echo " <object height=\"400\" width=\"475\">\n";
> echo " <param name=\"movie\" value=\"http://www.youtube.com/v/JqO8ZevPJNk\">\n";
> echo " <embed src=\"http://www.youtube.com/v/JqO8ZevPJNk\"\n";
> echo " type=\"application/x-shockwave-flash\" height=\"400\" width=\"475\">\n";
> echo " </object>\n";
> }
> else
> {
> echo " <a href=\"10538overturevideo.jpg\"><img SRC=\"10538overturevideo.jpg\" height=\"130\"></a>\n";
> }
> ?>
>
> Many thanks for any assistance you can provide.
>
> Robert Porter

You want to make a request for the headers, not for the file. If you
get a 200 OK response header, then the file exists.

<?php
$fp = fsockopen("www.youtube.com", 80, $errno, $errstr, 30);
if (!$fp) {
echo "$errstr ($errno)<br />\n";
} else {
$out = "HEAD http://www.youtube.com/v/JqO8ZevPJNk / HTTP/1.1\r\n";
$out .= "Host: www.youtube.com\r\n";
$out .= "Connection: Close\r\n\r\n";

fwrite($fp, $out);
$file_exists = false;
while (!feof($fp)) {
$header = fgets($fp, 128);
if(preg_match('#HTTP/1.1 200 OK#', $header)) {
$file_exists = true;

break;
}
}
fclose($fp);
if($file_exists) echo $header;
}
?>


--

_____________________
Myron Turner
http://www.room535.org
http://www.bstatzero.org
http://www.mturner.org/XML_PullParser/