PHP urlExists限制时间

Question

Im doing a simple webapp that that is used to display some server's status, included the state of the server (ON/OFF). To check the server's status I use the funciotion "urlExists" so if it returns me a true i shot that server as online, offline in the other case.

When I check a server, if it is online the function executes fast, but when the server that i am checking is offline it takes too long to check the next one. So I am trying to limit the execution time of the function like this:

...
set_time_limit(1);
$exists = false;
$exists = urlExists($url);
set_time_limit();
...

but the execution time is the same using the set_time_limit(). I dont know if set_time_limit is used to do this kind of things but is the only thing i founded. Any idea on how I can do this ??

Thanks in advance.

Answer 1

Try this function that uses CURL:

function urlExists($url)
{
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_NOBODY, true);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 1);

    $exists = curl_exec($ch);
    curl_close($ch);

    // If exec returns boolean, it's false, therefore the server is down/url doesn't exist.
    return !is_bool($exists);
}

As you can see, you can set a time limit for the connection with CURLOPT_CONNECTTIMEOUT. This way you don't need to set_time_limit();