[RESOLVED] check if remote available, how?

tullmejs

I successfully file_get_contents("http://asite.do/rss").

But the site is often down. How do I best check if it is currently available? If it is not, I want to quit trying at once.

First I tried

$fp = @fsockopen("asite.do/rss", 80, $errno, $errstr, 1);
if ($fp) {
$feed=file_get_contents("http://asite.do/rss");
... some stuff ...
}

But that never returned true, then tried

$fp = @fsockopen("asite.do", 80, $errno, $errstr, 1);
if ($fp) {
$feed=file_get_contents("http://asite.do/rss");
... some stuff ...
}

and it works fine when site is up, but when not my script does not quit trying.

Maybe I should do it in some completely different way. I am not really sure what I am doing here :-| . Please advice!

ab4net

try this :
<?php
$fp = fsockopen("www.mysite.com", 80, $errno, $errstr, 30);
if (!$fp) {
echo "$errstr ($errno)<br />\n";
#or any message you want ....
} else {
$out = "GET / HTTP/1.1\r\n";
$out .= "Host: www.mysite.com\r\n";
$out .= "Connection: Close\r\n\r\n";

fwrite($fp, $out);
while (!feof($fp)) {
echo fgets($fp, 128);
}
fclose($fp);
}
?>

i dont know it this is what you want or not ... check it ...

tullmejs

Thanks; your code does give me the contents of www.mysite.com, and it seems to quit gracefully when mysite is down. However:

fsockopen('www.mysite.com/rss',...,...,..,)

always fails (returns false), while

$var=file_get_contents('http://www.mysite.com/rss')

works as expected (when mysite is up).

My idea was to test www.mysite.com with fsockopen, then if not down retrieve www.mysite.com/rss with file_get_contents.

I don't know how to make fsockopen accept www.mysite.com/rss, and I don't know if it's necessary. It would resolve my issue, using your approach and dropping file_get_contents, if I could make fsockopen accept the /rss too. I suspect there are other ways, possibly better. I would be happy, though, with this way of doing it.

This ought to be a fairly common problem, but I haven't yet found much info, possibly because I am unfamiliar with socket manipulation and can't interpret what I read.

What I want is simply the script to give up if it cannot read a page instantly.

tullmejs

For now, I use fsockopen and a solution found in "file_exists with url" thread at webdeveloper.com board (can't get the link to paste properly here).

It still takes too long (several seconds) to "give up" (even when timeout=1).

Maybe I'll let a chronjob regularly run some code to save the remote info to file, for my page to access in a simpler, safer and fast way. Mmm, I'll try that.